linux-2.6-microblaze.git
2 years agomm/util.c: add warning if __vm_enough_memory fails
Kefeng Wang [Tue, 26 Jul 2022 14:54:28 +0000 (22:54 +0800)]
mm/util.c: add warning if __vm_enough_memory fails

If a process has not enough memory to allocate a new virtual mapping, we
may meet verious kinds of error, eg, fork cannot allocate memory, SIGBUS
error in shmem, but it is difficult to confirm them, let's add some debug
information to easily to check this scenario if __vm_enough_memory fails.

Link: https://lkml.kernel.org/r/20220726145428.8030-1-wangkefeng.wang@huawei.com
Reported-by: Yongqiang Liu <liuyongqiang13@huawei.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: add more BUILD_BUG_ONs to gfp_migratetype()
Peter Collingbourne [Tue, 26 Jul 2022 23:02:41 +0000 (16:02 -0700)]
mm: add more BUILD_BUG_ONs to gfp_migratetype()

gfp_migratetype() also expects GFP_RECLAIMABLE and
GFP_MOVABLE|GFP_RECLAIMABLE to be shiftable into MIGRATE_* enum values, so
add some more BUILD_BUG_ONs to reflect this assumption.

Link: https://linux-review.googlesource.com/id/Iae64e2182f75c3aca776a486b71a72571d66d83e
Link: https://lkml.kernel.org/r/20220726230241.3770532-1-pcc@google.com
Signed-off-by: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/gup.c: simplify and fix check_and_migrate_movable_pages() return codes
Alistair Popple [Fri, 29 Jul 2022 02:46:45 +0000 (12:46 +1000)]
mm/gup.c: simplify and fix check_and_migrate_movable_pages() return codes

When pinning pages with FOLL_LONGTERM check_and_migrate_movable_pages() is
called to migrate pages out of zones which should not contain any longterm
pinned pages.

When migration succeeds all pages will have been unpinned so pinning needs
to be retried.  This is indicated by returning zero.  When all pages are
in the correct zone the number of pinned pages is returned.

However migration can also fail, in which case pages are unpinned and
-ENOMEM is returned.  However if the failure was due to not being unable
to isolate a page zero is returned.  This leads to indefinite looping in
__gup_longterm_locked().

Fix this by simplifying the return codes such that zero indicates all
pages were successfully pinned in the correct zone while errors indicate
either pages were migrated and pinning should be retried or that migration
has failed and therefore the pinning operation should fail.

[syoshida@redhat.com: fix return value for __gup_longterm_locked()]
Link: https://lkml.kernel.org/r/20220821183547.950370-1-syoshida@redhat.com
[akpm@linux-foundation.org: fix code layout, per John]
[yshigeru@gmail.com: fix uninitialized return value on __gup_longterm_locked()]
Link: https://lkml.kernel.org/r/20220827230037.78876-1-syoshida@redhat.com
Link: https://lkml.kernel.org/r/20220729024645.764366-1-apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agohugetlb_cgroup: use helper for_each_hstate and hstate_index
Miaohe Lin [Fri, 29 Jul 2022 08:01:06 +0000 (16:01 +0800)]
hugetlb_cgroup: use helper for_each_hstate and hstate_index

Use helper for_each_hstate and hstate_index to iterate the hstate and get
the hstate index. Minor readability improvement.

Link: https://lkml.kernel.org/r/20220729080106.12752-6-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agohugetlb_cgroup: use helper macro NUMA_NO_NODE
Miaohe Lin [Fri, 29 Jul 2022 08:01:05 +0000 (16:01 +0800)]
hugetlb_cgroup: use helper macro NUMA_NO_NODE

It's better to use NUMA_NO_NODE instead of magic number -1. Minor
readability improvement.

Link: https://lkml.kernel.org/r/20220729080106.12752-5-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agohugetlb_cgroup: remove unneeded return value
Miaohe Lin [Fri, 29 Jul 2022 08:01:04 +0000 (16:01 +0800)]
hugetlb_cgroup: remove unneeded return value

The return value of set_hugetlb_cgroup and set_hugetlb_cgroup_rsvd are
always ignored. Remove them to clean up the code.

Link: https://lkml.kernel.org/r/20220729080106.12752-4-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mina Almasry <almasrymina@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agohugetlb_cgroup: hugetlbfs: use helper macro SZ_1{K,M,G}
Miaohe Lin [Fri, 29 Jul 2022 08:01:03 +0000 (16:01 +0800)]
hugetlb_cgroup: hugetlbfs: use helper macro SZ_1{K,M,G}

Use helper macro SZ_1K, SZ_1M and SZ_1G to do the size conversion. Minor
readability improvement.

Link: https://lkml.kernel.org/r/20220729080106.12752-3-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agohugetlb_cgroup: remove unneeded nr_pages > 0 check
Miaohe Lin [Fri, 29 Jul 2022 08:01:02 +0000 (16:01 +0800)]
hugetlb_cgroup: remove unneeded nr_pages > 0 check

Patch series "A few cleanup patches for hugetlb_cgroup", v2.

This series contains a few cleaup patches to remove unneeded check, use
helper macro, remove unneeded return value and so on.  More details can be
found in the respective changelogs.

This patch (of 5):

When code reaches here, nr_pages must be > 0. Remove unneeded nr_pages > 0
check to simplify the code.

Link: https://lkml.kernel.org/r/20220729080106.12752-1-linmiaohe@huawei.com
Link: https://lkml.kernel.org/r/20220729080106.12752-2-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoKselftests: remove support of libhugetlbfs from kselftests
Tarun Sahu [Mon, 1 Aug 2022 07:02:31 +0000 (12:32 +0530)]
Kselftests: remove support of libhugetlbfs from kselftests

libhugetlbfs, the user side utitlity to work with hugepages, does not have
any active support.  There are only 2 selftests which are part of in
vm/hmm_test.c that depends on libhugetlbfs.

This patch modifies the tests so that they will not require libhugetlb
library.

[axelrasmussen@google.com: : remove orphaned references to local_config.{h,mk}]
Link: https://lkml.kernel.org/r/20220831211526.2743216-1-axelrasmussen@google.com
Link: https://lkml.kernel.org/r/20220801070231.13831-1-tsahu@linux.ibm.com
Signed-off-by: Tarun Sahu <tsahu@linux.ibm.com>
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Tested-by: Zach O'Keefe <zokeefe@google.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Vaibhav Jain <vaibhav@linux.ibm.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokfence: add sysfs interface to disable kfence for selected slabs.
Imran Khan [Sun, 14 Aug 2022 19:53:53 +0000 (05:53 +1000)]
kfence: add sysfs interface to disable kfence for selected slabs.

By default kfence allocation can happen for any slab object, whose size is
up to PAGE_SIZE, as long as that allocation is the first allocation after
expiration of kfence sample interval.  But in certain debugging scenarios
we may be interested in debugging corruptions involving some specific slub
objects like dentry or ext4_* etc.  In such cases limiting kfence for
allocations involving only specific slub objects will increase the
probablity of catching the issue since kfence pool will not be consumed by
other slab objects.

This patch introduces a sysfs interface
'/sys/kernel/slab/<name>/skip_kfence' to disable kfence for specific
slabs.  Having the interface work in this way does not impact
current/default behavior of kfence and allows us to use kfence for
specific slabs (when needed) as well.  The decision to skip/use kfence is
taken depending on whether kmem_cache.flags has (newly introduced)
SLAB_SKIP_KFENCE flag set or not.

Link: https://lkml.kernel.org/r/20220814195353.2540848-1-imran.f.khan@oracle.com
Signed-off-by: Imran Khan <imran.f.khan@oracle.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: migration: fix the FOLL_GET failure on following huge page
Haiyue Wang [Fri, 12 Aug 2022 08:49:21 +0000 (16:49 +0800)]
mm: migration: fix the FOLL_GET failure on following huge page

Not all huge page APIs support FOLL_GET option, so move_pages() syscall
will fail to get the page node information for some huge pages.

Like x86 on linux 5.19 with 1GB huge page API follow_huge_pud(), it will
return NULL page for FOLL_GET when calling move_pages() syscall with the
NULL 'nodes' parameter, the 'status' parameter has '-2' error in array.

Note: follow_huge_pud() now supports FOLL_GET in linux 6.0.
Link: https://lore.kernel.org/all/20220714042420.1847125-3-naoya.horiguchi@linux.dev
But these huge page APIs don't support FOLL_GET:
  1. follow_huge_pud() in arch/s390/mm/hugetlbpage.c
  2. follow_huge_addr() in arch/ia64/mm/hugetlbpage.c
     It will cause WARN_ON_ONCE for FOLL_GET.
  3. follow_huge_pgd() in mm/hugetlb.c

This is an temporary solution to mitigate the side effect of the race
condition fix by calling follow_page() with FOLL_GET set for huge pages.

After supporting follow huge page by FOLL_GET is done, this fix can be
reverted safely.

Link: https://lkml.kernel.org/r/20220823135841.934465-2-haiyue.wang@intel.com
Link: https://lkml.kernel.org/r/20220812084921.409142-1-haiyue.wang@intel.com
Fixes: 4cd614841c06 ("mm: migration: fix possible do_pages_stat_array racing with memory offline")
Signed-off-by: Haiyue Wang <haiyue.wang@intel.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/vmscan: make the annotations of refaults code at the right place
Yang Yang [Sat, 13 Aug 2022 08:07:58 +0000 (08:07 +0000)]
mm/vmscan: make the annotations of refaults code at the right place

After patch "mm/workingset: prepare the workingset detection
infrastructure for anon LRU", we can handle the refaults of anonymous
pages too.  So the annotations of refaults should cover both of anonymous
pages and file pages.

Link: https://lkml.kernel.org/r/20220813080757.59131-1-yang.yang29@zte.com.cn
Fixes: 170b04b7ae4963 ("mm/workingset: prepare the workingset detection infrastructure for anon LRU")
Signed-off-by: Yang Yang <yang.yang29@zte.com.cn>
Signed-off-by: CGEL ZTE <cgel.zte@gmail.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/damon/core: simplify the parameter passing for region split operation
Kaixu Xia [Sat, 13 Aug 2022 15:19:03 +0000 (23:19 +0800)]
mm/damon/core: simplify the parameter passing for region split operation

The parameter 'struct damon_ctx *ctx' is unnecessary in damon region split
operation, so we can remove it.

Link: https://lkml.kernel.org/r/1660403943-29124-1-git-send-email-kaixuxia@tencent.com
Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agotools/vm/page_owner_sort: fix -f option
Yixuan Cao [Fri, 12 Aug 2022 15:55:15 +0000 (23:55 +0800)]
tools/vm/page_owner_sort: fix -f option

The -f option is to filter out the information of blocks whose memory has
not been released, I noticed some blocks should not be filtered out.

Commit 9cc7e96aa846 ("mm/page_owner: record timestamp and pid") records
the allocation timestamp (ts_nsec) of all pages.

Commit 866b48526217 ("mm/page_owner: record the timestamp of all pages
during free") records the free timestamp (free_ts_nsec) of all pages.
When the page is allocated for the first time, the initial value of
free_ts_nsec is 0, and the corresponding time will be obtained when the
page is released.  But during reallocation the free_ts_nsec will not reset
to 0 again.  In particular, when page migration occurs, these two
timestamps will be the same.

Now page_owner_sort removes all text blocks whose free_ts_nsec is not 0
when using -f option.  However, this way can only select pages allocated
for the first time.  If a freed page is reallocated, free_ts_nsec will be
less than ts_nsec; if page migration occurs, the two timestamps will be
equal.  These cases should be considered as pages are not released.

So I fix the function is_need() to keep text blocks that meet the above
two conditions when using -f option.

Link: https://lkml.kernel.org/r/20220812155515.30846-1-caoyixuan2019@email.szu.edu.cn
Signed-off-by: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>
Cc: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Yuhong Feng <yuhongf@szu.edu.cn>
Cc: Liam Mark <lmark@codeaurora.org>
Cc: Georgi Djakov <georgi.djakov@linaro.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/util: reduce stack usage of folio_mapcount
Kairui Song [Mon, 1 Aug 2022 17:31:55 +0000 (01:31 +0800)]
mm/util: reduce stack usage of folio_mapcount

folio_test_hugetlb() will call PageHeadHuge which is a function call,
and blocks the compiler from recognizing this redundant load.

After rearranging the code, stack usage is dropped from 32 to 24, and
the function size is smaller (tested on GCC 12):

Before:
Stack usage:
mm/util.c:845:5:folio_mapcount  32      static
Size:
0000000000000ea0 00000000000000c7 T folio_mapcount

After:
Stack usage:
mm/util.c:845:5:folio_mapcount  24      static
Size:
0000000000000ea0 00000000000000b0 T folio_mapcount

Link: https://lkml.kernel.org/r/20220801173155.92008-1-ryncsn@gmail.com
Signed-off-by: Kairui Song <kasong@tencent.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/page_alloc: only search higher order when fallback
Abel Wu [Wed, 3 Aug 2022 02:51:21 +0000 (10:51 +0800)]
mm/page_alloc: only search higher order when fallback

It seems unnecessary to search pages with order < alloc_order in
fallback allocation.

This can currently happen with ALLOC_NOFRAGMENT and alloc_order >
pageblock_order, so add a test to prevent it.

[vbabka@suse.cz: changelog addition]
Link: https://lkml.kernel.org/r/20220803025121.47018-1-wuyun.abel@bytedance.com
Signed-off-by: Abel Wu <wuyun.abel@bytedance.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agopage_alloc: remove inactive initialization
Li kunyu [Wed, 3 Aug 2022 06:41:18 +0000 (14:41 +0800)]
page_alloc: remove inactive initialization

The allocation address of the table pointer variable is first performed in
the function, no initialization assignment is required, and no invalid
pointer will appear.

Link: https://lkml.kernel.org/r/20220803064118.3664-1-kunyu@nfschina.com
Signed-off-by: Li kunyu <kunyu@nfschina.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/hugetlb: add dedicated func to get 'allowed' nodemask for current process
Feng Tang [Fri, 5 Aug 2022 00:59:03 +0000 (08:59 +0800)]
mm/hugetlb: add dedicated func to get 'allowed' nodemask for current process

Muchun Song found that after MPOL_PREFERRED_MANY policy was introduced in
commit b27abaccf8e8 ("mm/mempolicy: add MPOL_PREFERRED_MANY for multiple
preferred nodes"), the policy_nodemask_current()'s semantics for this new
policy has been changed, which returns 'preferred' nodes instead of
'allowed' nodes.

With the changed semantic of policy_nodemask_current, a task with
MPOL_PREFERRED_MANY policy could fail to get its reservation even though
it can fall back to other nodes (either defined by cpusets or all online
nodes) for that reservation failing mmap calles unnecessarily early.

The fix is to not consider MPOL_PREFERRED_MANY for reservations at all
because they, unlike MPOL_MBIND, do not pose any actual hard constrain.

Michal suggested the policy_nodemask_current() is only used by hugetlb,
and could be moved to hugetlb code with more explicit name to enforce the
'allowed' semantics for which only MPOL_BIND policy matters.

apply_policy_zone() is made extern to be called in hugetlb code and its
return value is changed to bool.

[1]. https://lore.kernel.org/lkml/20220801084207.39086-1-songmuchun@bytedance.com/t/

Link: https://lkml.kernel.org/r/20220805005903.95563-1-feng.tang@intel.com
Fixes: b27abaccf8e8 ("mm/mempolicy: add MPOL_PREFERRED_MANY for multiple preferred nodes")
Signed-off-by: Feng Tang <feng.tang@intel.com>
Reported-by: Muchun Song <songmuchun@bytedance.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Ben Widawsky <bwidawsk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/mempolicy: fix lock contention on mems_allowed
Abel Wu [Thu, 11 Aug 2022 12:41:57 +0000 (20:41 +0800)]
mm/mempolicy: fix lock contention on mems_allowed

The mems_allowed field can be modified by other tasks, so it isn't safe to
access it with alloc_lock unlocked even in the current process context.

Say there are two tasks: A from cpusetA is performing set_mempolicy(2),
and B is changing cpusetA's cpuset.mems:

  A (set_mempolicy) B (echo xx > cpuset.mems)
  -------------------------------------------------------
  pol = mpol_new();
update_tasks_nodemask(cpusetA) {
  foreach t in cpusetA {
    cpuset_change_task_nodemask(t) {
  mpol_set_nodemask(pol) {
      task_lock(t); // t could be A
    new = f(A->mems_allowed);
      update t->mems_allowed;
    pol.create(pol, new);
      task_unlock(t);
  }
    }
  }
}
  task_lock(A);
  A->mempolicy = pol;
  task_unlock(A);

In this case A's pol->nodes is computed by old mems_allowed, and could
be inconsistent with A's new mems_allowed.

While it is different when replacing vmas' policy: the pol->nodes is
gone wild only when current_cpuset_is_being_rebound():

  A (mbind) B (echo xx > cpuset.mems)
  -------------------------------------------------------
  pol = mpol_new();
  mmap_write_lock(A->mm);
cpuset_being_rebound = cpusetA;
update_tasks_nodemask(cpusetA) {
  foreach t in cpusetA {
    cpuset_change_task_nodemask(t) {
  mpol_set_nodemask(pol) {
      task_lock(t); // t could be A
    mask = f(A->mems_allowed);
      update t->mems_allowed;
    pol.create(pol, mask);
      task_unlock(t);
  }
    }
  foreach v in A->mm {
    if (cpuset_being_rebound == cpusetA)
      pol.rebind(pol, cpuset.mems);
    v->vma_policy = pol;
  }
  mmap_write_unlock(A->mm);
    mmap_write_lock(t->mm);
    mpol_rebind_mm(t->mm);
    mmap_write_unlock(t->mm);
  }
}
cpuset_being_rebound = NULL;

In this case, the cpuset.mems, which has already done updating, is finally
used for calculating pol->nodes, rather than A->mems_allowed.  So it is OK
to call mpol_set_nodemask() with alloc_lock unlocked when doing mbind(2).

Link: https://lkml.kernel.org/r/20220811124157.74888-1-wuyun.abel@bytedance.com
Fixes: 78b132e9bae9 ("mm/mempolicy: remove or narrow the lock on current")
Signed-off-by: Abel Wu <wuyun.abel@bytedance.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/cma_debug: show complete cma name in debugfs directories
Charan Teja Kalla [Thu, 11 Aug 2022 13:15:29 +0000 (18:45 +0530)]
mm/cma_debug: show complete cma name in debugfs directories

Currently only 12 characters of the cma name is being used as the debug
directories where as the cma name can be of length CMA_MAX_NAME(=64)
characters.  One side problem with this is having 2 cma's with first
common 12 characters would end up in trying to create directories with
same name and fails with -EEXIST thus can limit cma debug functionality.

The 'cma-' prefix is used initially where cma areas don't have any names
and are represented by simple integer values.  Since now each cma would be
having its own name, drop 'cma-' prefix for the cma debug directories as
they are clearly evident that they are for cma debug through creating them
in /sys/kernel/debug/cma/ path.

Link: https://lkml.kernel.org/r/1660223729-22461-1-git-send-email-quic_charante@quicinc.com
Signed-off-by: Charan Teja Kalla <quic_charante@quicinc.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Pavan Kondeti <quic_pkondeti@quicinc.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/swap: remove the end_write_func argument to __swap_writepage
Christoph Hellwig [Thu, 11 Aug 2022 14:17:41 +0000 (16:17 +0200)]
mm/swap: remove the end_write_func argument to __swap_writepage

The argument is always set to end_swap_bio_write, so remove the argument
and mark end_swap_bio_write static.

Link: https://lkml.kernel.org/r/20220811141741.660214-1-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agozsmalloc: remove unnecessary size_class NULL check
Alexey Romanov [Thu, 11 Aug 2022 15:37:55 +0000 (18:37 +0300)]
zsmalloc: remove unnecessary size_class NULL check

pool->size_class array elements can't be NULL, so this check
is not needed.

In the whole code, we assign pool->size_class[i] values that are
not NULL. Releasing memory for these values occurs in the
zs_destroy_pool() function, which also releases and destroys the pool.

In addition, in the zs_stats_size_show() and async_free_zspage(),
with similar iterations over the array, we don't check it for NULL
pointer.

Link: https://lkml.kernel.org/r/20220811153755.16102-3-avromanov@sberdevices.ru
Signed-off-by: Alexey Romanov <avromanov@sberdevices.ru>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agozsmalloc: zs_object_copy: add clarifying comment
Alexey Romanov [Thu, 11 Aug 2022 15:37:54 +0000 (18:37 +0300)]
zsmalloc: zs_object_copy: add clarifying comment

Patch series "tidy up zsmalloc implementation"

This patchset remove some unnecessary checks and adds a clarifying
comment.  While analysing zs_object_copy() function code, I spent some
time to understand what the call kunmap_atomic(d_addr) is for.  It seems
that this point is not trivial and it is worth adding a comment.

This patch (of 2):

It's not obvious why kunmap_atomic(d_addr) call is needed.

[akpm@linux-foundation.org: tweak comment layout]
Link: https://lkml.kernel.org/r/20220811153755.16102-1-avromanov@sberdevices.ru
Link: https://lkml.kernel.org/r/20220811153755.16102-2-avromanov@sberdevices.ru
Signed-off-by: Alexey Romanov <avromanov@sberdevices.ru>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/vmscan: define macros for refaults in struct lruvec
Yang Yang [Mon, 8 Aug 2022 00:56:45 +0000 (00:56 +0000)]
mm/vmscan: define macros for refaults in struct lruvec

The magic number 0 and 1 are used in several places in vmscan.c.
Define macros for them to improve code readability.

Link: https://lkml.kernel.org/r/20220808005644.1721066-1-yang.yang29@zte.com.cn
Signed-off-by: Yang Yang <yang.yang29@zte.com.cn>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoselftests: vm: add /dev/userfaultfd test cases to run_vmtests.sh
Axel Rasmussen [Mon, 8 Aug 2022 17:56:14 +0000 (10:56 -0700)]
selftests: vm: add /dev/userfaultfd test cases to run_vmtests.sh

This new mode was recently added to the userfaultfd selftest. We want to
exercise both userfaultfd(2) as well as /dev/userfaultfd, so add both
test cases to the script.

Link: https://lkml.kernel.org/r/20220808175614.3885028-6-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Acked-by: Peter Xu <peterx@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry V. Levin <ldv@altlinux.org>
Cc: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zhang Yi <yi.zhang@huawei.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agouserfaultfd: update documentation to describe /dev/userfaultfd
Axel Rasmussen [Mon, 8 Aug 2022 17:56:13 +0000 (10:56 -0700)]
userfaultfd: update documentation to describe /dev/userfaultfd

Explain the different ways to create a new userfaultfd, and how access
control works for each way.

[axelrasmussen@google.com: improve wording in documentation, per Mike]
Link: https://lkml.kernel.org/r/20220819205201.658693-5-axelrasmussen@google.com
Link: https://lkml.kernel.org/r/20220808175614.3885028-5-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry V. Levin <ldv@altlinux.org>
Cc: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zhang Yi <yi.zhang@huawei.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agouserfaultfd: selftests: modify selftest to use /dev/userfaultfd
Axel Rasmussen [Mon, 8 Aug 2022 17:56:12 +0000 (10:56 -0700)]
userfaultfd: selftests: modify selftest to use /dev/userfaultfd

We clearly want to ensure both userfaultfd(2) and /dev/userfaultfd keep
working into the future, so just run the test twice, using each interface.

Instead of always testing both userfaultfd(2) and /dev/userfaultfd, let
the user choose which to test.

As with other test features, change the behavior based on a new command
line flag.  Introduce the idea of "test mods", which are generic (not
specific to a test type) modifications to the behavior of the test.  This
is sort of borrowed from this RFC patch series [1], but simplified a bit.

The benefit is, in "typical" configurations this test is somewhat slow
(say, 30sec or something).  Testing both clearly doubles it, so it may not
always be desirable, as users are likely to use one or the other, but
never both, in the "real world".

[1]: https://patchwork.kernel.org/project/linux-mm/patch/20201129004548.1619714-14-namit@vmware.com/

[axelrasmussen@google.com: modify selftest to exit with KSFT_SKIP *only* when features are unsupported, per Mike]
Link: https://lkml.kernel.org/r/20220819205201.658693-4-axelrasmussen@google.com
Link: https://lkml.kernel.org/r/20220808175614.3885028-4-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Acked-by: Peter Xu <peterx@redhat.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry V. Levin <ldv@altlinux.org>
Cc: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zhang Yi <yi.zhang@huawei.com>
Cc: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agouserfaultfd: add /dev/userfaultfd for fine grained access control
Axel Rasmussen [Mon, 8 Aug 2022 17:56:11 +0000 (10:56 -0700)]
userfaultfd: add /dev/userfaultfd for fine grained access control

Historically, it has been shown that intercepting kernel faults with
userfaultfd (thereby forcing the kernel to wait for an arbitrary amount of
time) can be exploited, or at least can make some kinds of exploits
easier.  So, in 37cd0575b8 "userfaultfd: add UFFD_USER_MODE_ONLY" we
changed things so, in order for kernel faults to be handled by
userfaultfd, either the process needs CAP_SYS_PTRACE, or this sysctl must
be configured so that any unprivileged user can do it.

In a typical implementation of a hypervisor with live migration (take
QEMU/KVM as one such example), we do indeed need to be able to handle
kernel faults.  But, both options above are less than ideal:

- Toggling the sysctl increases attack surface by allowing any
  unprivileged user to do it.

- Granting the live migration process CAP_SYS_PTRACE gives it this
  ability, but *also* the ability to "observe and control the
  execution of another process [...], and examine and change [its]
  memory and registers" (from ptrace(2)). This isn't something we need
  or want to be able to do, so granting this permission violates the
  "principle of least privilege".

This is all a long winded way to say: we want a more fine-grained way to
grant access to userfaultfd, without granting other additional permissions
at the same time.

To achieve this, add a /dev/userfaultfd misc device.  This device provides
an alternative to the userfaultfd(2) syscall for the creation of new
userfaultfds.  The idea is, any userfaultfds created this way will be able
to handle kernel faults, without the caller having any special
capabilities.  Access to this mechanism is instead restricted using e.g.
standard filesystem permissions.

[axelrasmussen@google.com: Handle misc_register() failure properly]
Link: https://lkml.kernel.org/r/20220819205201.658693-3-axelrasmussen@google.com
Link: https://lkml.kernel.org/r/20220808175614.3885028-3-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Acked-by: Nadav Amit <namit@vmware.com>
Acked-by: Peter Xu <peterx@redhat.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry V. Levin <ldv@altlinux.org>
Cc: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zhang Yi <yi.zhang@huawei.com>
Cc: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoselftests: vm: add hugetlb_shared userfaultfd test to run_vmtests.sh
Axel Rasmussen [Mon, 8 Aug 2022 17:56:10 +0000 (10:56 -0700)]
selftests: vm: add hugetlb_shared userfaultfd test to run_vmtests.sh

Patch series "userfaultfd: add /dev/userfaultfd for fine grained access
control", v7.

Why not ...?
============

- Why not /proc/[pid]/userfaultfd? Two main points (additional discussion [1]):

    - /proc/[pid]/* files are all owned by the user/group of the process, and
      they don't really support chmod/chown. So, without extending procfs it
      doesn't solve the problem this series is trying to solve.

    - The main argument *for* this was to support creating UFFDs for remote
      processes. But, that use case clearly calls for CAP_SYS_PTRACE, so to
      support this we could just use the UFFD syscall as-is.

- Why not use a syscall? Access to syscalls is generally controlled by
  capabilities. We don't have a capability which is used for userfaultfd access
  without also granting more / other permissions as well, and adding a new
  capability was rejected [2].

    - It's possible a LSM could be used to control access instead, but I have
      some concerns. I don't think this approach would be as easy to use,
      particularly if we were to try to solve this with something heavyweight
      like SELinux. Maybe we could pursue adding a new LSM specifically for
      this user case, but it may be too narrow of a case to justify that.

[1]: https://patchwork.kernel.org/project/linux-mm/cover/20220719195628.3415852-1-axelrasmussen@google.com/
[2]: https://lore.kernel.org/lkml/686276b9-4530-2045-6bd8-170e5943abe4@schaufler-ca.com/T/

This patch (of 5):

This not being included was just a simple oversight.  There are certain
features (like minor fault support) which are only enabled on shared
mappings, so without including hugetlb_shared we actually lose a
significant amount of test coverage.

Link: https://lkml.kernel.org/r/20220808175614.3885028-1-axelrasmussen@google.com
Link: https://lkml.kernel.org/r/20220808175614.3885028-2-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry V. Levin <ldv@altlinux.org>
Cc: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zhang Yi <yi.zhang@huawei.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/damon/dbgfs: use kmalloc for allocating only one element
Kenneth Lee [Mon, 8 Aug 2022 22:00:19 +0000 (15:00 -0700)]
mm/damon/dbgfs: use kmalloc for allocating only one element

Use kmalloc(...) rather than kmalloc_array(1, ...) because the number of
elements we are specifying in this case is 1, kmalloc would accomplish the
same thing and we can simplify.

Link: https://lkml.kernel.org/r/20220808220019.1680469-1-klee33@uw.edu
Signed-off-by: Kenneth Lee <klee33@uw.edu>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/filemap.c: convert page_endio() to use a folio
Shaoqin Huang [Tue, 9 Aug 2022 02:32:56 +0000 (10:32 +0800)]
mm/filemap.c: convert page_endio() to use a folio

Replace three calls to compound_head() with one.

Link: https://lkml.kernel.org/r/20220809023256.178194-1-shaoqin.huang@intel.com
Signed-off-by: Shaoqin Huang <shaoqin.huang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: memory-failure: cleanup try_to_split_thp_page()
Kefeng Wang [Tue, 9 Aug 2022 11:18:13 +0000 (19:18 +0800)]
mm: memory-failure: cleanup try_to_split_thp_page()

Since commit 5d1fd5dc877b ("mm,hwpoison: introduce MF_MSG_UNSPLIT_THP"),
the action_result(,MF_MSG_UNSPLIT_THP,) called to show memory error event
in memory_failure(), so the pr_info() in try_to_split_thp_page() is only
needed in soft_offline_in_use_page().

Meanwhile this could also fix the unexpected prefix for "thp split failed"
due to commit 96f96763de26 ("mm: memory-failure: convert to pr_fmt()").

Link: https://lkml.kernel.org/r/20220809111813.139690-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: align larger anonymous mappings on THP boundaries
Rik van Riel [Tue, 9 Aug 2022 18:24:57 +0000 (14:24 -0400)]
mm: align larger anonymous mappings on THP boundaries

Align larger anonymous memory mappings on THP boundaries by going through
thp_get_unmapped_area if THPs are enabled for the current process.

With this patch, larger anonymous mappings are now THP aligned.  When a
malloc library allocates a 2MB or larger arena, that arena can now be
mapped with THPs right from the start, which can result in better TLB hit
rates and execution time.

Link: https://lkml.kernel.org/r/20220809142457.4751229f@imladris.surriel.com
Signed-off-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/page_ext: remove unused variable in offline_page_ext
Charan Teja Kalla [Mon, 1 Aug 2022 05:06:37 +0000 (10:36 +0530)]
mm/page_ext: remove unused variable in offline_page_ext

Remove unused variable 'nid' in offline_page_ext().  This is not used
since the page_ext code inception.

Link: https://lkml.kernel.org/r/1659330397-11817-1-git-send-email-quic_charante@quicinc.com
Signed-off-by: Charan Teja Kalla <quic_charante@quicinc.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Pavan Kondeti <quic_pkondeti@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoselftests/vm: add selftest to verify multi THP collapse
Zach O'Keefe [Wed, 6 Jul 2022 23:59:36 +0000 (16:59 -0700)]
selftests/vm: add selftest to verify multi THP collapse

Add support to allocate and verify collapse of multiple hugepage-sized
regions into multiple THPs.

Add "nr" argument to check_huge() that instructs check_huge() to check for
exactly "nr_hpages" THPs.  This has the added benefit of now being able to
check for exactly 0 THPs, and so callsites that previously checked the
negation of exactly 1 THP are now more correct.

->collapse struct collapse_context hook has been expanded with a
"nr_hpages" argument to collapse "nr_hpages" hugepages.  The
collapse_full() test has been repurposed to collapse 4 THPs at once.  It
is expected more tests will want to test multi THP collapse (e.g.
file/shmem).

This is of particular benefit to madvise collapse context given that it
may do many THP collapses during a single syscall.

Link: https://lkml.kernel.org/r/20220706235936.2197195-19-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoselftests/vm: add selftest to verify recollapse of THPs
Zach O'Keefe [Wed, 6 Jul 2022 23:59:35 +0000 (16:59 -0700)]
selftests/vm: add selftest to verify recollapse of THPs

Add selftest specific to madvise collapse context that tests MADV_COLLAPSE
is "successful" if a hugepage-aligned/sized region is already pmd-mapped.

This test also verifies that MADV_COLLAPSE can collapse memory into THPs
even in "madvise" THP mode and the memory isn't marked VM_HUGEPAGE.

Link: https://lkml.kernel.org/r/20220706235936.2197195-18-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoselftests/vm: add MADV_COLLAPSE collapse context to selftests
Zach O'Keefe [Wed, 6 Jul 2022 23:59:34 +0000 (16:59 -0700)]
selftests/vm: add MADV_COLLAPSE collapse context to selftests

Add madvise collapse context to hugepage collapse selftests.  This context
is tested with /sys/kernel/mm/transparent_hugepage/enabled set to "never"
in order to avoid unwanted interaction with khugepaged during testing.

Also, refactor updates to sysfs THP settings using a stack so that the THP
settings from nested callers can be restored.

Link: https://lkml.kernel.org/r/20220706235936.2197195-17-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoselftests/vm: dedup hugepage allocation logic
Zach O'Keefe [Wed, 6 Jul 2022 23:59:33 +0000 (16:59 -0700)]
selftests/vm: dedup hugepage allocation logic

The code

p = alloc_mapping();
printf("Allocate huge page...");
madvise(p, hpage_pmd_size, MADV_HUGEPAGE);
fill_memory(p, 0, hpage_pmd_size);
if (check_huge(p))
success("OK");
else
fail("Fail");

Is repeated many times in different tests.  Add a helper, alloc_hpage()
to handle this.

Link: https://lkml.kernel.org/r/20220706235936.2197195-16-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoselftests/vm: modularize collapse selftests
Zach O'Keefe [Wed, 6 Jul 2022 23:59:32 +0000 (16:59 -0700)]
selftests/vm: modularize collapse selftests

Modularize the collapse action of khugepaged collapse selftests by
introducing a struct collapse_context which specifies how to collapse a
given memory range and the expected semantics of the collapse.  This can
be reused later to test other collapse contexts.

Additionally, all tests have logic that checks if a collapse occurred via
reading /proc/self/smaps, and report if this is different than expected.
Move this logic into the per-context ->collapse() hook instead of
repeating it in every test.

Link: https://lkml.kernel.org/r/20220706235936.2197195-15-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/madvise: add MADV_COLLAPSE to process_madvise()
Zach O'Keefe [Wed, 6 Jul 2022 23:59:30 +0000 (16:59 -0700)]
mm/madvise: add MADV_COLLAPSE to process_madvise()

Allow MADV_COLLAPSE behavior for process_madvise(2) if caller has
CAP_SYS_ADMIN or is requesting collapse of it's own memory.

This is useful for the development of userspace agents that seek to
optimize THP utilization system-wide by using userspace signals to
prioritize what memory is most deserving of being THP-backed.

[zokeefe@google.com: remove CAP_SYS_ADMIN requirement for process_madvise(MADV_COLLAPSE)]
Link: https://lkml.kernel.org/r/20220801210946.3069083-1-zokeefe@google.com
Link: https://lkml.kernel.org/r/20220706235936.2197195-13-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/khugepaged: rename prefix of shared collapse functions
Zach O'Keefe [Wed, 6 Jul 2022 23:59:28 +0000 (16:59 -0700)]
mm/khugepaged: rename prefix of shared collapse functions

The following functions are shared between khugepaged and madvise collapse
contexts.  Replace the "khugepaged_" prefix with generic "hpage_collapse_"
prefix in such cases:

khugepaged_test_exit() -> hpage_collapse_test_exit()
khugepaged_scan_abort() -> hpage_collapse_scan_abort()
khugepaged_scan_pmd() -> hpage_collapse_scan_pmd()
khugepaged_find_target_node() -> hpage_collapse_find_target_node()
khugepaged_alloc_page() -> hpage_collapse_alloc_page()

The kerenel ABI (e.g.  huge_memory:mm_khugepaged_scan_pmd tracepoint) is
unaltered.

Link: https://lkml.kernel.org/r/20220706235936.2197195-11-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/madvise: introduce MADV_COLLAPSE sync hugepage collapse
Zach O'Keefe [Wed, 6 Jul 2022 23:59:27 +0000 (16:59 -0700)]
mm/madvise: introduce MADV_COLLAPSE sync hugepage collapse

This idea was introduced by David Rientjes[1].

Introduce a new madvise mode, MADV_COLLAPSE, that allows users to request
a synchronous collapse of memory at their own expense.

The benefits of this approach are:

* CPU is charged to the process that wants to spend the cycles for the
  THP
* Avoid unpredictable timing of khugepaged collapse

Semantics

This call is independent of the system-wide THP sysfs settings, but will
fail for memory marked VM_NOHUGEPAGE.  If the ranges provided span
multiple VMAs, the semantics of the collapse over each VMA is independent
from the others.  This implies a hugepage cannot cross a VMA boundary.  If
collapse of a given hugepage-aligned/sized region fails, the operation may
continue to attempt collapsing the remainder of memory specified.

The memory ranges provided must be page-aligned, but are not required to
be hugepage-aligned.  If the memory ranges are not hugepage-aligned, the
start/end of the range will be clamped to the first/last hugepage-aligned
address covered by said range.  The memory ranges must span at least one
hugepage-sized region.

All non-resident pages covered by the range will first be
swapped/faulted-in, before being internally copied onto a freshly
allocated hugepage.  Unmapped pages will have their data directly
initialized to 0 in the new hugepage.  However, for every eligible
hugepage aligned/sized region to-be collapsed, at least one page must
currently be backed by memory (a PMD covering the address range must
already exist).

Allocation for the new hugepage may enter direct reclaim and/or
compaction, regardless of VMA flags.  When the system has multiple NUMA
nodes, the hugepage will be allocated from the node providing the most
native pages.  This operation operates on the current state of the
specified process and makes no persistent changes or guarantees on how
pages will be mapped, constructed, or faulted in the future

Return Value

If all hugepage-sized/aligned regions covered by the provided range were
either successfully collapsed, or were already PMD-mapped THPs, this
operation will be deemed successful.  On success, process_madvise(2)
returns the number of bytes advised, and madvise(2) returns 0.  Else, -1
is returned and errno is set to indicate the error for the most-recently
attempted hugepage collapse.  Note that many failures might have occurred,
since the operation may continue to collapse in the event a single
hugepage-sized/aligned region fails.

ENOMEM Memory allocation failed or VMA not found
EBUSY Memcg charging failed
EAGAIN Required resource temporarily unavailable.  Try again
might succeed.
EINVAL Other error: No PMD found, subpage doesn't have Present
bit set, "Special" page no backed by struct page, VMA
incorrectly sized, address not page-aligned, ...

Most notable here is ENOMEM and EBUSY (new to madvise) which are intended
to provide the caller with actionable feedback so they may take an
appropriate fallback measure.

Use Cases

An immediate user of this new functionality are malloc() implementations
that manage memory in hugepage-sized chunks, but sometimes subrelease
memory back to the system in native-sized chunks via MADV_DONTNEED;
zapping the pmd.  Later, when the memory is hot, the implementation could
madvise(MADV_COLLAPSE) to re-back the memory by THPs to regain hugepage
coverage and dTLB performance.  TCMalloc is such an implementation that
could benefit from this[2].

Only privately-mapped anon memory is supported for now, but additional
support for file, shmem, and HugeTLB high-granularity mappings[2] is
expected.  File and tmpfs/shmem support would permit:

* Backing executable text by THPs.  Current support provided by
  CONFIG_READ_ONLY_THP_FOR_FS may take a long time on a large system which
  might impair services from serving at their full rated load after
  (re)starting.  Tricks like mremap(2)'ing text onto anonymous memory to
  immediately realize iTLB performance prevents page sharing and demand
  paging, both of which increase steady state memory footprint.  With
  MADV_COLLAPSE, we get the best of both worlds: Peak upfront performance
  and lower RAM footprints.
* Backing guest memory by hugapages after the memory contents have been
  migrated in native-page-sized chunks to a new host, in a
  userfaultfd-based live-migration stack.

[1] https://lore.kernel.org/linux-mm/d098c392-273a-36a4-1a29-59731cdf5d3d@google.com/
[2] https://github.com/google/tcmalloc/tree/master/tcmalloc

[jrdr.linux@gmail.com: avoid possible memory leak in failure path]
Link: https://lkml.kernel.org/r/20220713024109.62810-1-jrdr.linux@gmail.com
[zokeefe@google.com add missing kfree() to madvise_collapse()]
Link: https://lore.kernel.org/linux-mm/20220713024109.62810-1-jrdr.linux@gmail.com/
Link: https://lkml.kernel.org/r/20220713161851.1879439-1-zokeefe@google.com
[zokeefe@google.com: delay computation of hpage boundaries until use]]
Link: https://lkml.kernel.org/r/20220720140603.1958773-4-zokeefe@google.com
Link: https://lkml.kernel.org/r/20220706235936.2197195-10-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Suggested-by: David Rientjes <rientjes@google.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/khugepaged: record SCAN_PMD_MAPPED when scan_pmd() finds hugepage
Zach O'Keefe [Wed, 6 Jul 2022 23:59:26 +0000 (16:59 -0700)]
mm/khugepaged: record SCAN_PMD_MAPPED when scan_pmd() finds hugepage

When scanning an anon pmd to see if it's eligible for collapse, return
SCAN_PMD_MAPPED if the pmd already maps a hugepage.  Note that
SCAN_PMD_MAPPED is different from SCAN_PAGE_COMPOUND used in the
file-collapse path, since the latter might identify pte-mapped compound
pages.  This is required by MADV_COLLAPSE which necessarily needs to know
what hugepage-aligned/sized regions are already pmd-mapped.

In order to determine if a pmd already maps a hugepage, refactor
mm_find_pmd():

Return mm_find_pmd() to it's pre-commit f72e7dcdd252 ("mm: let mm_find_pmd
fix buggy race with THP fault") behavior.  ksm was the only caller that
explicitly wanted a pte-mapping pmd, so open code the pte-mapping logic
there (pmd_present() and pmd_trans_huge() checks).

Undo revert change in commit f72e7dcdd252 ("mm: let mm_find_pmd fix buggy
race with THP fault") that open-coded split_huge_pmd_address() pmd lookup
and use mm_find_pmd() instead.

Link: https://lkml.kernel.org/r/20220706235936.2197195-9-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/thp: add flag to enforce sysfs THP in hugepage_vma_check()
Zach O'Keefe [Wed, 6 Jul 2022 23:59:25 +0000 (16:59 -0700)]
mm/thp: add flag to enforce sysfs THP in hugepage_vma_check()

MADV_COLLAPSE is not coupled to the kernel-oriented sysfs THP settings[1].

hugepage_vma_check() is the authority on determining if a VMA is eligible
for THP allocation/collapse, and currently enforces the sysfs THP
settings.  Add a flag to disable these checks.  For now, only apply this
arg to anon and file, which use /sys/kernel/transparent_hugepage/enabled.
We can expand this to shmem, which uses
/sys/kernel/transparent_hugepage/shmem_enabled, later.

Use this flag in collapse_pte_mapped_thp() where previously the VMA flags
passed to hugepage_vma_check() were OR'd with VM_HUGEPAGE to elide the
VM_HUGEPAGE check in "madvise" THP mode.  Prior to "mm: khugepaged: check
THP flag in hugepage_vma_check()", this check also didn't check "never"
THP mode.  As such, this restores the previous behavior of
collapse_pte_mapped_thp() where sysfs THP settings are ignored.  See
comment in code for justification why this is OK.

[1] https://lore.kernel.org/linux-mm/CAAa6QmQxay1_=Pmt8oCX2-Va18t44FV-Vs-WsQt_6+qBks4nZA@mail.gmail.com/

Link: https://lkml.kernel.org/r/20220706235936.2197195-8-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/khugepaged: add flag to predicate khugepaged-only behavior
Zach O'Keefe [Wed, 6 Jul 2022 23:59:24 +0000 (16:59 -0700)]
mm/khugepaged: add flag to predicate khugepaged-only behavior

Add .is_khugepaged flag to struct collapse_control so khugepaged-specific
behavior can be elided by MADV_COLLAPSE context.

Start by protecting khugepaged-specific heuristics by this flag.  In
MADV_COLLAPSE, the user presumably has reason to believe the collapse will
be beneficial and khugepaged heuristics shouldn't prevent the user from
doing so:

1) sysfs-controlled knobs khugepaged_max_ptes_[none|swap|shared]

2) requirement that some pages in region being collapsed be young or
   referenced

[zokeefe@google.com: consistently order cc->is_khugepaged and pte_* checks]
Link: https://lkml.kernel.org/r/20220720140603.1958773-3-zokeefe@google.com
Link: https://lore.kernel.org/linux-mm/Ys2qJm6FaOQcxkha@google.com/
Link: https://lkml.kernel.org/r/20220706235936.2197195-7-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/khugepaged: propagate enum scan_result codes back to callers
Zach O'Keefe [Wed, 6 Jul 2022 23:59:23 +0000 (16:59 -0700)]
mm/khugepaged: propagate enum scan_result codes back to callers

Propagate enum scan_result codes back through return values of
functions downstream of khugepaged_scan_file() and
khugepaged_scan_pmd() to inform callers if the operation was
successful, and if not, why.

Since khugepaged_scan_pmd()'s return value already has a specific meaning
(whether mmap_lock was unlocked or not), add a bool* argument to
khugepaged_scan_pmd() to retrieve this information.

Change khugepaged to take action based on the return values of
khugepaged_scan_file() and khugepaged_scan_pmd() instead of acting deep
within the collapsing functions themselves.

hugepage_vma_revalidate() now returns SCAN_SUCCEED on success to be more
consistent with enum scan_result propagation.

Remove dependency on error pointers to communicate to khugepaged that
allocation failed and it should sleep; instead just use the result of the
scan (SCAN_ALLOC_HUGE_PAGE_FAIL if allocation fails).

Link: https://lkml.kernel.org/r/20220706235936.2197195-6-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/khugepaged: dedup and simplify hugepage alloc and charging
Zach O'Keefe [Wed, 6 Jul 2022 23:59:22 +0000 (16:59 -0700)]
mm/khugepaged: dedup and simplify hugepage alloc and charging

The following code is duplicated in collapse_huge_page() and
collapse_file():

        gfp = alloc_hugepage_khugepaged_gfpmask() | __GFP_THISNODE;

new_page = khugepaged_alloc_page(hpage, gfp, node);
        if (!new_page) {
                result = SCAN_ALLOC_HUGE_PAGE_FAIL;
                goto out;
        }

        if (unlikely(mem_cgroup_charge(page_folio(new_page), mm, gfp))) {
                result = SCAN_CGROUP_CHARGE_FAIL;
                goto out;
        }
        count_memcg_page_event(new_page, THP_COLLAPSE_ALLOC);

Also, "node" is passed as an argument to both collapse_huge_page() and
collapse_file() and obtained the same way, via
khugepaged_find_target_node().

Move all this into a new helper, alloc_charge_hpage(), and remove the
duplicate code from collapse_huge_page() and collapse_file().  Also,
simplify khugepaged_alloc_page() by returning a bool indicating allocation
success instead of a copy of the allocated struct page *.

Link: https://lkml.kernel.org/r/20220706235936.2197195-5-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Suggested-by: Peter Xu <peterx@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/khugepaged: add struct collapse_control
Zach O'Keefe [Wed, 6 Jul 2022 23:59:21 +0000 (16:59 -0700)]
mm/khugepaged: add struct collapse_control

Modularize hugepage collapse by introducing struct collapse_control.  This
structure serves to describe the properties of the requested collapse, as
well as serve as a local scratch pad to use during the collapse itself.

Start by moving global per-node khugepaged statistics into this new
structure.  Note that this structure is still statically allocated since
CONFIG_NODES_SHIFT might be arbitrary large, and stack-allocating a
MAX_NUMNODES-sized array could cause -Wframe-large-than= errors.

[zokeefe@google.com: use minimal bits to store num page < HPAGE_PMD_NR]
Link: https://lkml.kernel.org/r/20220720140603.1958773-2-zokeefe@google.com
Link: https://lore.kernel.org/linux-mm/Ys2CeIm%2FQmQwWh9a@google.com/
[sfr@canb.auug.org.au: fix build]
Link: https://lkml.kernel.org/r/20220721195508.15f1e07a@canb.auug.org.au
[zokeefe@google.com: fix struct collapse_control load_node definition]
Link: https://lore.kernel.org/linux-mm/202209021349.F73i5d6X-lkp@intel.com/
Link: https://lkml.kernel.org/r/20220903021221.1130021-1-zokeefe@google.com
Link: https://lkml.kernel.org/r/20220706235936.2197195-4-zokeefe@google.com
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: khugepaged: don't carry huge page to the next loop for !CONFIG_NUMA
Yang Shi [Wed, 6 Jul 2022 23:59:20 +0000 (16:59 -0700)]
mm: khugepaged: don't carry huge page to the next loop for !CONFIG_NUMA

Patch series "mm: userspace hugepage collapse", v7.

Introduction
--------------------------------

This series provides a mechanism for userspace to induce a collapse of
eligible ranges of memory into transparent hugepages in process context,
thus permitting users to more tightly control their own hugepage
utilization policy at their own expense.

This idea was introduced by David Rientjes[5].

Interface
--------------------------------

The proposed interface adds a new madvise(2) mode, MADV_COLLAPSE, and
leverages the new process_madvise(2) call.

process_madvise(2)

Performs a synchronous collapse of the native pages
mapped by the list of iovecs into transparent hugepages.

This operation is independent of the system THP sysfs settings,
but attempts to collapse VMAs marked VM_NOHUGEPAGE will still fail.

THP allocation may enter direct reclaim and/or compaction.

When a range spans multiple VMAs, the semantics of the collapse
over of each VMA is independent from the others.

Caller must have CAP_SYS_ADMIN if not acting on self.

Return value follows existing process_madvise(2) conventions.  A
“success” indicates that all hugepage-sized/aligned regions
covered by the provided range were either successfully
collapsed, or were already pmd-mapped THPs.

madvise(2)

Equivalent to process_madvise(2) on self, with 0 returned on
“success”.

Current Use-Cases
--------------------------------

(1) Immediately back executable text by THPs.  Current support provided
by CONFIG_READ_ONLY_THP_FOR_FS may take a long time on a large
system which might impair services from serving at their full rated
load after (re)starting.  Tricks like mremap(2)'ing text onto
anonymous memory to immediately realize iTLB performance prevents
page sharing and demand paging, both of which increase steady state
memory footprint.  With MADV_COLLAPSE, we get the best of both
worlds: Peak upfront performance and lower RAM footprints.  Note
that subsequent support for file-backed memory is required here.

(2) malloc() implementations that manage memory in hugepage-sized
chunks, but sometimes subrelease memory back to the system in
native-sized chunks via MADV_DONTNEED; zapping the pmd.  Later,
when the memory is hot, the implementation could
madvise(MADV_COLLAPSE) to re-back the memory by THPs to regain
hugepage coverage and dTLB performance.  TCMalloc is such an
implementation that could benefit from this[6].  A prior study of
Google internal workloads during evaluation of Temeraire, a
hugepage-aware enhancement to TCMalloc, showed that nearly 20% of
all cpu cycles were spent in dTLB stalls, and that increasing
hugepage coverage by even small amount can help with that[7].

(3) userfaultfd-based live migration of virtual machines satisfy UFFD
faults by fetching native-sized pages over the network (to avoid
latency of transferring an entire hugepage).  However, after guest
memory has been fully copied to the new host, MADV_COLLAPSE can
be used to immediately increase guest performance.  Note that
subsequent support for file/shmem-backed memory is required here.

(4) HugeTLB high-granularity mapping allows HugeTLB a HugeTLB page to
be mapped at different levels in the page tables[8].  As it's not
"transparent" like THP, HugeTLB high-granularity mappings require
an explicit user API. It is intended that MADV_COLLAPSE be co-opted
for this use case[9].  Note that subsequent support for HugeTLB
memory is required here.

Future work
--------------------------------

Only private anonymous memory is supported by this series. File and
shmem memory support will be added later.

One possible user of this functionality is a userspace agent that
attempts to optimize THP utilization system-wide by allocating THPs
based on, for example, task priority, task performance requirements, or
heatmaps.  For the latter, one idea that has already surfaced is using
DAMON to identify hot regions, and driving THP collapse through a new
DAMOS_COLLAPSE scheme[10].

This patch (of 17):

The khugepaged has optimization to reduce huge page allocation calls for
!CONFIG_NUMA by carrying the allocated but failed to collapse huge page to
the next loop.  CONFIG_NUMA doesn't do so since the next loop may try to
collapse huge page from a different node, so it doesn't make too much
sense to carry it.

But when NUMA=n, the huge page is allocated by khugepaged_prealloc_page()
before scanning the address space, so it means huge page may be allocated
even though there is no suitable range for collapsing.  Then the page
would be just freed if khugepaged already made enough progress.  This
could make NUMA=n run have 5 times as much thp_collapse_alloc as NUMA=y
run.  This problem actually makes things worse due to the way more
pointless THP allocations and makes the optimization pointless.

This could be fixed by carrying the huge page across scans, but it will
complicate the code further and the huge page may be carried indefinitely.
But if we take one step back, the optimization itself seems not worth
keeping nowadays since:

  * Not too many users build NUMA=n kernel nowadays even though the kernel is
    actually running on a non-NUMA machine. Some small devices may run NUMA=n
    kernel, but I don't think they actually use THP.
  * Since commit 44042b449872 ("mm/page_alloc: allow high-order pages to be
    stored on the per-cpu lists"), THP could be cached by pcp.  This actually
    somehow does the job done by the optimization.

Link: https://lkml.kernel.org/r/20220706235936.2197195-1-zokeefe@google.com
Link: https://lkml.kernel.org/r/20220706235936.2197195-3-zokeefe@google.com
Signed-off-by: Yang Shi <shy828301@gmail.com>
Signed-off-by: Zach O'Keefe <zokeefe@google.com>
Co-developed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Chris Kennelly <ckennelly@google.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Souptick Joarder (HPE)" <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoLinux 6.0-rc3
Linus Torvalds [Sun, 28 Aug 2022 22:05:29 +0000 (15:05 -0700)]
Linux 6.0-rc3

2 years agoMerge tag 'mm-hotfixes-stable-2022-08-28' of git://git.kernel.org/pub/scm/linux/kerne...
Linus Torvalds [Sun, 28 Aug 2022 21:49:59 +0000 (14:49 -0700)]
Merge tag 'mm-hotfixes-stable-2022-08-28' of git://git./linux/kernel/git/akpm/mm

Pull more hotfixes from Andrew Morton:
 "Seventeen hotfixes.  Mostly memory management things.

  Ten patches are cc:stable, addressing pre-6.0 issues"

* tag 'mm-hotfixes-stable-2022-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  .mailmap: update Luca Ceresoli's e-mail address
  mm/mprotect: only reference swap pfn page if type match
  squashfs: don't call kmalloc in decompressors
  mm/damon/dbgfs: avoid duplicate context directory creation
  mailmap: update email address for Colin King
  asm-generic: sections: refactor memory_intersects
  bootmem: remove the vmemmap pages from kmemleak in put_page_bootmem
  ocfs2: fix freeing uninitialized resource on ocfs2_dlm_shutdown
  Revert "memcg: cleanup racy sum avoidance code"
  mm/zsmalloc: do not attempt to free IS_ERR handle
  binder_alloc: add missing mmap_lock calls when using the VMA
  mm: re-allow pinning of zero pfns (again)
  vmcoreinfo: add kallsyms_num_syms symbol
  mailmap: update Guilherme G. Piccoli's email addresses
  writeback: avoid use-after-free after removing device
  shmem: update folio if shmem_replace_page() updates the page
  mm/hugetlb: avoid corrupting page->mapping in hugetlb_mcopy_atomic_pte

2 years agoMerge tag 'bitmap-6.0-rc3' of github.com:/norov/linux
Linus Torvalds [Sun, 28 Aug 2022 21:36:27 +0000 (14:36 -0700)]
Merge tag 'bitmap-6.0-rc3' of github.com:/norov/linux

Pull bitmap fixes from Yury Norov:
 "Fix the reported issues, and implements the suggested improvements,
  for the version of the cpumask tests [1] that was merged with commit
  c41e8866c28c ("lib/test: introduce cpumask KUnit test suite").

  These changes include fixes for the tests, and better alignment with
  the KUnit style guidelines"

* tag 'bitmap-6.0-rc3' of github.com:/norov/linux:
  lib/cpumask_kunit: add tests file to MAINTAINERS
  lib/cpumask_kunit: log mask contents
  lib/test_cpumask: follow KUnit style guidelines
  lib/test_cpumask: fix cpu_possible_mask last test
  lib/test_cpumask: drop cpu_possible_mask full test

2 years ago.mailmap: update Luca Ceresoli's e-mail address
Luca Ceresoli [Fri, 26 Aug 2022 13:05:15 +0000 (15:05 +0200)]
.mailmap: update Luca Ceresoli's e-mail address

My Bootlin address is preferred from now on.

Link: https://lkml.kernel.org/r/20220826130515.3011951-1-luca.ceresoli@bootlin.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Atish Patra <atishp@atishpatra.org>
Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/mprotect: only reference swap pfn page if type match
Peter Xu [Tue, 23 Aug 2022 22:11:38 +0000 (18:11 -0400)]
mm/mprotect: only reference swap pfn page if type match

Yu Zhao reported a bug after the commit "mm/swap: Add swp_offset_pfn() to
fetch PFN from swap entry" added a check in swp_offset_pfn() for swap type [1]:

  kernel BUG at include/linux/swapops.h:117!
  CPU: 46 PID: 5245 Comm: EventManager_De Tainted: G S         O L 6.0.0-dbg-DEV #2
  RIP: 0010:pfn_swap_entry_to_page+0x72/0xf0
  Code: c6 48 8b 36 48 83 fe ff 74 53 48 01 d1 48 83 c1 08 48 8b 09 f6
  c1 01 75 7b 66 90 48 89 c1 48 8b 09 f6 c1 01 74 74 5d c3 eb 9e <0f> 0b
  48 ba ff ff ff ff 03 00 00 00 eb ae a9 ff 0f 00 00 75 13 48
  RSP: 0018:ffffa59e73fabb80 EFLAGS: 00010282
  RAX: 00000000ffffffe8 RBX: 0c00000000000000 RCX: ffffcd5440000000
  RDX: 1ffffffffff7a80a RSI: 0000000000000000 RDI: 0c0000000000042b
  RBP: ffffa59e73fabb80 R08: ffff9965ca6e8bb8 R09: 0000000000000000
  R10: ffffffffa5a2f62d R11: 0000030b372e9fff R12: ffff997b79db5738
  R13: 000000000000042b R14: 0c0000000000042b R15: 1ffffffffff7a80a
  FS:  00007f549d1bb700(0000) GS:ffff99d3cf680000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000440d035b3180 CR3: 0000002243176004 CR4: 00000000003706e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   <TASK>
   change_pte_range+0x36e/0x880
   change_p4d_range+0x2e8/0x670
   change_protection_range+0x14e/0x2c0
   mprotect_fixup+0x1ee/0x330
   do_mprotect_pkey+0x34c/0x440
   __x64_sys_mprotect+0x1d/0x30

It triggers because pfn_swap_entry_to_page() could be called upon e.g. a
genuine swap entry.

Fix it by only calling it when it's a write migration entry where the page*
is used.

[1] https://lore.kernel.org/lkml/CAOUHufaVC2Za-p8m0aiHw6YkheDcrO-C3wRGixwDS32VTS+k1w@mail.gmail.com/

Link: https://lkml.kernel.org/r/20220823221138.45602-1-peterx@redhat.com
Fixes: 6c287605fd56 ("mm: remember exclusively mapped anonymous pages with PG_anon_exclusive")
Signed-off-by: Peter Xu <peterx@redhat.com>
Reported-by: Yu Zhao <yuzhao@google.com>
Tested-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agosquashfs: don't call kmalloc in decompressors
Phillip Lougher [Mon, 22 Aug 2022 21:54:30 +0000 (22:54 +0100)]
squashfs: don't call kmalloc in decompressors

The decompressors may be called while in an atomic section.  So move the
kmalloc() out of this path, and into the "page actor" init function.

This fixes a regression introduced by commit
f268eedddf35 ("squashfs: extend "page actor" to handle missing pages")

Link: https://lkml.kernel.org/r/20220822215430.15933-1-phillip@squashfs.org.uk
Fixes: f268eedddf35 ("squashfs: extend "page actor" to handle missing pages")
Reported-by: Chris Murphy <lists@colorremedies.com>
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/damon/dbgfs: avoid duplicate context directory creation
Badari Pulavarty [Sun, 21 Aug 2022 18:08:53 +0000 (18:08 +0000)]
mm/damon/dbgfs: avoid duplicate context directory creation

When user tries to create a DAMON context via the DAMON debugfs interface
with a name of an already existing context, the context directory creation
fails but a new context is created and added in the internal data
structure, due to absence of the directory creation success check.  As a
result, memory could leak and DAMON cannot be turned on.  An example test
case is as below:

    # cd /sys/kernel/debug/damon/
    # echo "off" >  monitor_on
    # echo paddr > target_ids
    # echo "abc" > mk_context
    # echo "abc" > mk_context
    # echo $$ > abc/target_ids
    # echo "on" > monitor_on  <<< fails

Return value of 'debugfs_create_dir()' is expected to be ignored in
general, but this is an exceptional case as DAMON feature is depending
on the debugfs functionality and it has the potential duplicate name
issue.  This commit therefore fixes the issue by checking the directory
creation failure and immediately return the error in the case.

Link: https://lkml.kernel.org/r/20220821180853.2400-1-sj@kernel.org
Fixes: 75c1c2b53c78 ("mm/damon/dbgfs: support multiple contexts")
Signed-off-by: Badari Pulavarty <badari.pulavarty@intel.com>
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> [ 5.15.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomailmap: update email address for Colin King
Colin Ian King [Wed, 17 Aug 2022 21:27:53 +0000 (22:27 +0100)]
mailmap: update email address for Colin King

Colin King is working on kernel janitorial fixes in his spare time and
using his Intel email is confusing.  Use his gmail account as the default
email address.

Link: https://lkml.kernel.org/r/20220817212753.101109-1-colin.i.king@gmail.com
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoasm-generic: sections: refactor memory_intersects
Quanyang Wang [Fri, 19 Aug 2022 08:11:45 +0000 (16:11 +0800)]
asm-generic: sections: refactor memory_intersects

There are two problems with the current code of memory_intersects:

First, it doesn't check whether the region (begin, end) falls inside the
region (virt, vend), that is (virt < begin && vend > end).

The second problem is if vend is equal to begin, it will return true but
this is wrong since vend (virt + size) is not the last address of the
memory region but (virt + size -1) is.  The wrong determination will
trigger the misreporting when the function check_for_illegal_area calls
memory_intersects to check if the dma region intersects with stext region.

The misreporting is as below (stext is at 0x80100000):
 WARNING: CPU: 0 PID: 77 at kernel/dma/debug.c:1073 check_for_illegal_area+0x130/0x168
 DMA-API: chipidea-usb2 e0002000.usb: device driver maps memory from kernel text or rodata [addr=800f0000] [len=65536]
 Modules linked in:
 CPU: 1 PID: 77 Comm: usb-storage Not tainted 5.19.0-yocto-standard #5
 Hardware name: Xilinx Zynq Platform
  unwind_backtrace from show_stack+0x18/0x1c
  show_stack from dump_stack_lvl+0x58/0x70
  dump_stack_lvl from __warn+0xb0/0x198
  __warn from warn_slowpath_fmt+0x80/0xb4
  warn_slowpath_fmt from check_for_illegal_area+0x130/0x168
  check_for_illegal_area from debug_dma_map_sg+0x94/0x368
  debug_dma_map_sg from __dma_map_sg_attrs+0x114/0x128
  __dma_map_sg_attrs from dma_map_sg_attrs+0x18/0x24
  dma_map_sg_attrs from usb_hcd_map_urb_for_dma+0x250/0x3b4
  usb_hcd_map_urb_for_dma from usb_hcd_submit_urb+0x194/0x214
  usb_hcd_submit_urb from usb_sg_wait+0xa4/0x118
  usb_sg_wait from usb_stor_bulk_transfer_sglist+0xa0/0xec
  usb_stor_bulk_transfer_sglist from usb_stor_bulk_srb+0x38/0x70
  usb_stor_bulk_srb from usb_stor_Bulk_transport+0x150/0x360
  usb_stor_Bulk_transport from usb_stor_invoke_transport+0x38/0x440
  usb_stor_invoke_transport from usb_stor_control_thread+0x1e0/0x238
  usb_stor_control_thread from kthread+0xf8/0x104
  kthread from ret_from_fork+0x14/0x2c

Refactor memory_intersects to fix the two problems above.

Before the 1d7db834a027e ("dma-debug: use memory_intersects()
directly"), memory_intersects is called only by printk_late_init:

printk_late_init -> init_section_intersects ->memory_intersects.

There were few places where memory_intersects was called.

When commit 1d7db834a027e ("dma-debug: use memory_intersects()
directly") was merged and CONFIG_DMA_API_DEBUG is enabled, the DMA
subsystem uses it to check for an illegal area and the calltrace above
is triggered.

[akpm@linux-foundation.org: fix nearby comment typo]
Link: https://lkml.kernel.org/r/20220819081145.948016-1-quanyang.wang@windriver.com
Fixes: 979559362516 ("asm/sections: add helpers to check for section data")
Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thierry Reding <treding@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agobootmem: remove the vmemmap pages from kmemleak in put_page_bootmem
Liu Shixin [Fri, 19 Aug 2022 09:40:05 +0000 (17:40 +0800)]
bootmem: remove the vmemmap pages from kmemleak in put_page_bootmem

The vmemmap pages is marked by kmemleak when allocated from memblock.
Remove it from kmemleak when freeing the page.  Otherwise, when we reuse
the page, kmemleak may report such an error and then stop working.

 kmemleak: Cannot insert 0xffff98fb6eab3d40 into the object search tree (overlaps existing)
 kmemleak: Kernel memory leak detector disabled
 kmemleak: Object 0xffff98fb6be00000 (size 335544320):
 kmemleak:   comm "swapper", pid 0, jiffies 4294892296
 kmemleak:   min_count = 0
 kmemleak:   count = 0
 kmemleak:   flags = 0x1
 kmemleak:   checksum = 0
 kmemleak:   backtrace:

Link: https://lkml.kernel.org/r/20220819094005.2928241-1-liushixin2@huawei.com
Fixes: f41f2ed43ca5 (mm: hugetlb: free the vmemmap pages associated with each HugeTLB page)
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoocfs2: fix freeing uninitialized resource on ocfs2_dlm_shutdown
Heming Zhao [Mon, 15 Aug 2022 08:57:54 +0000 (16:57 +0800)]
ocfs2: fix freeing uninitialized resource on ocfs2_dlm_shutdown

After commit 0737e01de9c4 ("ocfs2: ocfs2_mount_volume does cleanup job
before return error"), any procedure after ocfs2_dlm_init() fails will
trigger crash when calling ocfs2_dlm_shutdown().

ie: On local mount mode, no dlm resource is initialized.  If
ocfs2_mount_volume() fails in ocfs2_find_slot(), error handling will call
ocfs2_dlm_shutdown(), then does dlm resource cleanup job, which will
trigger kernel crash.

This solution should bypass uninitialized resources in
ocfs2_dlm_shutdown().

Link: https://lkml.kernel.org/r/20220815085754.20417-1-heming.zhao@suse.com
Fixes: 0737e01de9c4 ("ocfs2: ocfs2_mount_volume does cleanup job before return error")
Signed-off-by: Heming Zhao <heming.zhao@suse.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoRevert "memcg: cleanup racy sum avoidance code"
Shakeel Butt [Wed, 17 Aug 2022 17:21:39 +0000 (17:21 +0000)]
Revert "memcg: cleanup racy sum avoidance code"

This reverts commit 96e51ccf1af33e82f429a0d6baebba29c6448d0f.

Recently we started running the kernel with rstat infrastructure on
production traffic and begin to see negative memcg stats values.
Particularly the 'sock' stat is the one which we observed having negative
value.

$ grep "sock " /mnt/memory/job/memory.stat
sock 253952
total_sock 18446744073708724224

Re-run after couple of seconds

$ grep "sock " /mnt/memory/job/memory.stat
sock 253952
total_sock 53248

For now we are only seeing this issue on large machines (256 CPUs) and
only with 'sock' stat.  I think the networking stack increase the stat on
one cpu and decrease it on another cpu much more often.  So, this negative
sock is due to rstat flusher flushing the stats on the CPU that has seen
the decrement of sock but missed the CPU that has increments.  A typical
race condition.

For easy stable backport, revert is the most simple solution.  For long
term solution, I am thinking of two directions.  First is just reduce the
race window by optimizing the rstat flusher.  Second is if the reader sees
a negative stat value, force flush and restart the stat collection.
Basically retry but limited.

Link: https://lkml.kernel.org/r/20220817172139.3141101-1-shakeelb@google.com
Fixes: 96e51ccf1af33e8 ("memcg: cleanup racy sum avoidance code")
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Cc: "Michal Koutný" <mkoutny@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: <stable@vger.kernel.org> [5.15]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/zsmalloc: do not attempt to free IS_ERR handle
Sergey Senozhatsky [Tue, 16 Aug 2022 05:09:06 +0000 (14:09 +0900)]
mm/zsmalloc: do not attempt to free IS_ERR handle

zsmalloc() now returns ERR_PTR values as handles, which zram accidentally
can pass to zs_free().  Another bad scenario is when zcomp_compress()
fails - handle has default -ENOMEM value, and zs_free() will try to free
that "pointer value".

Add the missing check and make sure that zs_free() bails out when
ERR_PTR() is passed to it.

Link: https://lkml.kernel.org/r/20220816050906.2583956-1-senozhatsky@chromium.org
Fixes: c7e6f17b52e9 ("zsmalloc: zs_malloc: return ERR_PTR on failure")
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>,
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agobinder_alloc: add missing mmap_lock calls when using the VMA
Liam Howlett [Wed, 10 Aug 2022 16:02:25 +0000 (16:02 +0000)]
binder_alloc: add missing mmap_lock calls when using the VMA

Take the mmap_read_lock() when using the VMA in binder_alloc_print_pages()
and when checking for a VMA in binder_alloc_new_buf_locked().

It is worth noting binder_alloc_new_buf_locked() drops the VMA read lock
after it verifies a VMA exists, but may be taken again deeper in the call
stack, if necessary.

Link: https://lkml.kernel.org/r/20220810160209.1630707-1-Liam.Howlett@oracle.com
Fixes: a43cfc87caaf (android: binder: stop saving a pointer to the VMA)
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reported-by: Ondrej Mosnacek <omosnace@redhat.com>
Reported-by: <syzbot+a7b60a176ec13cafb793@syzkaller.appspotmail.com>
Acked-by: Carlos Llamas <cmllamas@google.com>
Tested-by: Ondrej Mosnacek <omosnace@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Christian Brauner (Microsoft) <brauner@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hridya Valsaraju <hridya@google.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Martijn Coenen <maco@android.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Todd Kjos <tkjos@android.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: "Arve Hjønnevåg" <arve@android.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: re-allow pinning of zero pfns (again)
Alex Williamson [Wed, 10 Aug 2022 16:53:59 +0000 (10:53 -0600)]
mm: re-allow pinning of zero pfns (again)

The below referenced commit makes the same error as 1c563432588d ("mm: fix
is_pinnable_page against a cma page"), re-interpreting the logic to
exclude pinning of the zero page, which breaks device assignment with
vfio.

To avoid further subtle mistakes, split the logic into discrete tests.

[akpm@linux-foundation.org: simplify comment, per John]
Link: https://lkml.kernel.org/r/166015037385.760108.16881097713975517242.stgit@omen
Link: https://lore.kernel.org/all/165490039431.944052.12458624139225785964.stgit@omen
Fixes: f25cbb7a95a2 ("mm: add zone device coherent type memory support")
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Suggested-by: Felix Kuehling <felix.kuehling@amd.com>
Tested-by: Slawomir Laba <slawomirx.laba@intel.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: Alex Sierra <alex.sierra@amd.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agovmcoreinfo: add kallsyms_num_syms symbol
Stephen Brennan [Mon, 8 Aug 2022 20:54:10 +0000 (13:54 -0700)]
vmcoreinfo: add kallsyms_num_syms symbol

The rest of the kallsyms symbols are useless without knowing the number of
symbols in the table.  In an earlier patch, I somehow dropped the
kallsyms_num_syms symbol, so add it back in.

Link: https://lkml.kernel.org/r/20220808205410.18590-1-stephen.s.brennan@oracle.com
Fixes: 5fd8fea935a1 ("vmcoreinfo: include kallsyms symbols")
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomailmap: update Guilherme G. Piccoli's email addresses
Guilherme G. Piccoli [Thu, 4 Aug 2022 20:22:07 +0000 (17:22 -0300)]
mailmap: update Guilherme G. Piccoli's email addresses

Both @canonical and @ibm email addresses are invalid now; use my personal
address instead.

Link: https://lkml.kernel.org/r/20220804202207.439427-1-gpiccoli@igalia.com
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agowriteback: avoid use-after-free after removing device
Khazhismel Kumykov [Mon, 1 Aug 2022 15:50:34 +0000 (08:50 -0700)]
writeback: avoid use-after-free after removing device

When a disk is removed, bdi_unregister gets called to stop further
writeback and wait for associated delayed work to complete.  However,
wb_inode_writeback_end() may schedule bandwidth estimation dwork after
this has completed, which can result in the timer attempting to access the
just freed bdi_writeback.

Fix this by checking if the bdi_writeback is alive, similar to when
scheduling writeback work.

Since this requires wb->work_lock, and wb_inode_writeback_end() may get
called from interrupt, switch wb->work_lock to an irqsafe lock.

Link: https://lkml.kernel.org/r/20220801155034.3772543-1-khazhy@google.com
Fixes: 45a2966fd641 ("writeback: fix bandwidth estimate for spiky workload")
Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Michael Stapelberg <stapelberg+linux@google.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: update folio if shmem_replace_page() updates the page
Matthew Wilcox (Oracle) [Sat, 30 Jul 2022 04:25:18 +0000 (05:25 +0100)]
shmem: update folio if shmem_replace_page() updates the page

If we allocate a new page, we need to make sure that our folio matches
that new page.

If we do end up in this code path, we store the wrong page in the shmem
inode's page cache, and I would rather imagine that data corruption
ensues.

This will be solved by changing shmem_replace_page() to
shmem_replace_folio(), but this is the minimal fix.

Link: https://lkml.kernel.org/r/20220730042518.1264767-1-willy@infradead.org
Fixes: da08e9b79323 ("mm/shmem: convert shmem_swapin_page() to shmem_swapin_folio()")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/hugetlb: avoid corrupting page->mapping in hugetlb_mcopy_atomic_pte
Miaohe Lin [Tue, 12 Jul 2022 13:05:42 +0000 (21:05 +0800)]
mm/hugetlb: avoid corrupting page->mapping in hugetlb_mcopy_atomic_pte

In MCOPY_ATOMIC_CONTINUE case with a non-shared VMA, pages in the page
cache are installed in the ptes.  But hugepage_add_new_anon_rmap is called
for them mistakenly because they're not vm_shared.  This will corrupt the
page->mapping used by page cache code.

Link: https://lkml.kernel.org/r/20220712130542.18836-1-linmiaohe@huawei.com
Fixes: f619147104c8 ("userfaultfd: add UFFDIO_CONTINUE ioctl")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoMerge tag 'for-6.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave...
Linus Torvalds [Sun, 28 Aug 2022 17:44:04 +0000 (10:44 -0700)]
Merge tag 'for-6.0-rc3-tag' of git://git./linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "Fixes:

   - check that subvolume is writable when changing xattrs from security
     namespace

   - fix memory leak in device lookup helper

   - update generation of hole file extent item when merging holes

   - fix space cache corruption and potential double allocations; this
     is a rare bug but can be serious once it happens, stable backports
     and analysis tool will be provided

   - fix error handling when deleting root references

   - fix crash due to assert when attempting to cancel suspended device
     replace, add message what to do if mount fails due to missing
     replace item

  Regressions:

   - don't merge pages into bio if their page offset is not contiguous

   - don't allow large NOWAIT direct reads, this could lead to short
     reads eg. in io_uring"

* tag 'for-6.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: add info when mount fails due to stale replace target
  btrfs: replace: drop assert for suspended replace
  btrfs: fix silent failure when deleting root reference
  btrfs: fix space cache corruption and potential double allocations
  btrfs: don't allow large NOWAIT direct reads
  btrfs: don't merge pages into bio if their page offset is not contiguous
  btrfs: update generation of hole file extent item when merging holes
  btrfs: fix possible memory leak in btrfs_get_dev_args_from_path()
  btrfs: check if root is readonly while setting security xattr

2 years agoMerge tag '6.0-rc2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6
Linus Torvalds [Sun, 28 Aug 2022 17:35:16 +0000 (10:35 -0700)]
Merge tag '6.0-rc2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cfis fixes from Steve French:

 - two locking fixes (zero range, punch hole)

 - DFS 9 fix (padding), affecting some servers

 - three minor cleanup changes

* tag '6.0-rc2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: Add helper function to check smb1+ server
  cifs: Use help macro to get the mid header size
  cifs: Use help macro to get the header preamble size
  cifs: skip extra NULL byte in filenames
  smb3: missing inode locks in punch hole
  smb3: missing inode locks in zero range

2 years agoMerge tag 'x86-urgent-2022-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sun, 28 Aug 2022 17:10:23 +0000 (10:10 -0700)]
Merge tag 'x86-urgent-2022-08-28' of git://git./linux/kernel/git/tip/tip

Pull misc x86 fixes from Ingo Molnar:

 - Fix PAT on Xen, which caused i915 driver failures

 - Fix compat INT 80 entry crash on Xen PV guests

 - Fix 'MMIO Stale Data' mitigation status reporting on older Intel CPUs

 - Fix RSB stuffing regressions

 - Fix ORC unwinding on ftrace trampolines

 - Add Intel Raptor Lake CPU model number

 - Fix (work around) a SEV-SNP bootloader bug providing bogus values in
   boot_params->cc_blob_address, by ignoring the value on !SEV-SNP
   bootups.

 - Fix SEV-SNP early boot failure

 - Fix the objtool list of noreturn functions and annotate snp_abort(),
   which bug confused objtool on gcc-12.

 - Fix the documentation for retbleed

* tag 'x86-urgent-2022-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Documentation/ABI: Mention retbleed vulnerability info file for sysfs
  x86/sev: Mark snp_abort() noreturn
  x86/sev: Don't use cc_platform_has() for early SEV-SNP calls
  x86/boot: Don't propagate uninitialized boot_params->cc_blob_address
  x86/cpu: Add new Raptor Lake CPU model number
  x86/unwind/orc: Unwind ftrace trampolines with correct ORC entry
  x86/nospec: Fix i386 RSB stuffing
  x86/nospec: Unwreck the RSB stuffing
  x86/bugs: Add "unknown" reporting for MMIO Stale Data
  x86/entry: Fix entry_INT80_compat for Xen PV guests
  x86/PAT: Have pat_enabled() properly reflect state when running on Xen

2 years agoMerge tag 'perf-urgent-2022-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sun, 28 Aug 2022 17:05:42 +0000 (10:05 -0700)]
Merge tag 'perf-urgent-2022-08-28' of git://git./linux/kernel/git/tip/tip

Pull x86 perf fixes from Ingo Molnar:
 "Misc fixes: an Arch-LBR fix, a PEBS enumeration fix, an Intel DS fix,
  PEBS constraints fix on Alder Lake CPUs and an Intel uncore PMU fix"

* tag 'perf-urgent-2022-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/uncore: Fix broken read_counter() for SNB IMC PMU
  perf/x86/intel: Fix pebs event constraints for ADL
  perf/x86/intel/ds: Fix precise store latency handling
  perf/x86/core: Set pebs_capable and PMU_FL_PEBS_ALL for the Baseline
  perf/x86/lbr: Enable the branch type for the Arch LBR by default

2 years agoMerge tag 'perf-tools-fixes-for-v6.0-2022-08-27' of git://git.kernel.org/pub/scm...
Linus Torvalds [Sun, 28 Aug 2022 16:58:00 +0000 (09:58 -0700)]
Merge tag 'perf-tools-fixes-for-v6.0-2022-08-27' of git://git./linux/kernel/git/acme/linux

Pull perf tools fixes from Arnaldo Carvalho de Melo:

 - Fixup setup of weak groups when using 'perf stat --repeat', add a
   'perf test' for it.

 - Fix memory leaks in 'perf sched record' detected with
   -fsanitize=address.

 - Fix build when PYTHON_CONFIG is user supplied.

 - Capitalize topdown metrics' names in 'perf stat', so that the output,
   sometimes parsed, matches the Intel SDM docs.

 - Make sure the documentation for the save_type filter about Intel
   systems with Arch LBR support (12th-Gen+ client or 4th-Gen Xeon+
   server) reflects recent related kernel changes.

 - Fix 'perf record' man page formatting of description of support to
   hybrid systems.

 - Update arm64´s KVM header from the kernel sources.

* tag 'perf-tools-fixes-for-v6.0-2022-08-27' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
  perf stat: Capitalize topdown metrics' names
  perf docs: Update the documentation for the save_type filter
  perf sched: Fix memory leaks in __cmd_record detected with -fsanitize=address
  perf record: Fix manpage formatting of description of support to hybrid systems
  perf test: Stat test for repeat with a weak group
  perf stat: Clear evsel->reset_group for each stat run
  tools kvm headers arm64: Update KVM header from the kernel sources
  perf python: Fix build when PYTHON_CONFIG is user supplied

2 years agoMerge tag 'thermal-6.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael...
Linus Torvalds [Sat, 27 Aug 2022 22:58:38 +0000 (15:58 -0700)]
Merge tag 'thermal-6.0-rc3' of git://git./linux/kernel/git/rafael/linux-pm

Pull thermal control fixes from Rafael Wysocki:
 "Fix two issues introduced recently and one driver problem leading to a
  NULL pointer dereference in some cases.

  Specifics:

   - Add missing EXPORT_SYMBOL_GPL in the thermal core and add back the
     required 'trips' property to the thermal zone DT bindings (Daniel
     Lezcano)

   - Prevent the int340x_thermal driver from crashing when a package
     with a buffer of 0 length is returned by an ACPI control method
     evaluated by it (Lee, Chun-Yi)"

* tag 'thermal-6.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  thermal/int340x_thermal: handle data_vault when the value is ZERO_SIZE_PTR
  dt-bindings: thermal: Fix missing required property
  thermal/core: Add missing EXPORT_SYMBOL_GPL

2 years agoMerge tag 'pm-6.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Linus Torvalds [Sat, 27 Aug 2022 22:53:49 +0000 (15:53 -0700)]
Merge tag 'pm-6.0-rc3' of git://git./linux/kernel/git/rafael/linux-pm

Pull power management fix from Rafael Wysocki:
 "Make __resolve_freq() check the presence of the frequency table
  instead of checking whether or not the ->target_index() callback is
  implemented by the driver, because that need not be the case when
  __resolve_freq() is used (Lukasz Luba)"

* tag 'pm-6.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: check only freq_table in __resolve_freq()

2 years agoMerge tag 'acpi-6.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael...
Linus Torvalds [Sat, 27 Aug 2022 22:47:02 +0000 (15:47 -0700)]
Merge tag 'acpi-6.0-rc3' of git://git./linux/kernel/git/rafael/linux-pm

Pull ACPI fixes from Rafael Wysocki:
 "These fix issues introduced by recent changes related to the handling
  of ACPI device properties and a coding mistake in the exit path of the
  ACPI processor driver.

  Specifics:

   - Prevent acpi_thermal_cpufreq_exit() from attempting to remove
     the same frequency QoS request multiple times (Riwen Lu)

   - Fix type detection for integer ACPI device properties (Stefan
     Binding)

   - Avoid emitting false-positive warnings when processing ACPI
     device properties and drop the useless default case from the
     acpi_copy_property_array_uint() macro (Sakari Ailus)"

* tag 'acpi-6.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: property: Remove default association from integer maximum values
  ACPI: property: Ignore already existing data node tags
  ACPI: property: Fix type detection of unified integer reading functions
  ACPI: processor: Remove freq Qos request for all CPUs

2 years agoMerge tag 's390-6.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Linus Torvalds [Sat, 27 Aug 2022 22:40:51 +0000 (15:40 -0700)]
Merge tag 's390-6.0-2' of git://git./linux/kernel/git/s390/linux

Pull s390 fixes from Vasily Gorbik:

 - Fix double free of guarded storage and runtime instrumentation
   control blocks on fork() failure

 - Fix triggering write fault when VMA does not allow VM_WRITE

* tag 's390-6.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/mm: do not trigger write fault when vma does not allow VM_WRITE
  s390: fix double free of GS and RI CBs on fork() failure

2 years agoMerge tag 'for-linus-6.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sat, 27 Aug 2022 22:38:00 +0000 (15:38 -0700)]
Merge tag 'for-linus-6.0-rc3-tag' of git://git./linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:

 - two minor cleanups

 - a fix of the xen/privcmd driver avoiding a possible NULL dereference
   in an error case

* tag 'for-linus-6.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/privcmd: fix error exit of privcmd_ioctl_dm_op()
  xen: move from strlcpy with unused retval to strscpy
  xen: x86: remove setting the obsolete config XEN_MAX_DOMAIN_MEMORY

2 years agoMerge tag 'audit-pr-20220826' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoor...
Linus Torvalds [Sat, 27 Aug 2022 22:31:12 +0000 (15:31 -0700)]
Merge tag 'audit-pr-20220826' of git://git./linux/kernel/git/pcmoore/audit

Pull audit fix from Paul Moore:
 "Another small audit patch, this time to fix a bug where the return
  codes were not properly set before the audit filters were run,
  potentially resulting in missed audit records"

* tag 'audit-pr-20220826' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
  audit: move audit_return_fixup before the filters

2 years agoMerge tag 'fbdev-for-6.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller...
Linus Torvalds [Sat, 27 Aug 2022 16:57:58 +0000 (09:57 -0700)]
Merge tag 'fbdev-for-6.0-rc3' of git://git./linux/kernel/git/deller/linux-fbdev

Pull fbdev fixes and updates from Helge Deller:
 "Mostly just small patches, with the exception of the bigger indenting
  cleanups in the sisfb and radeonfb drivers.

  Two patches should be mentioned though: A fix-up for fbdev if the
  screen resize fails (by Shigeru Yoshida), and a potential divide by
  zero fix in fb_pm2fb (by Letu Ren).

  Summary:

  Major fixes:
   - Revert the changes for fbcon console when vc_resize() fails
     [Shigeru Yoshida]
   - Avoid a potential divide by zero error in fb_pm2fb [Letu Ren]

  Minor fixes:
   - Add missing pci_disable_device() in chipsfb_pci_init() [Yang
     Yingliang]
   - Fix tests for platform_get_irq() failure in omapfb [Yu Zhe]
   - Destroy mutex on freeing struct fb_info in fbsysfs [Shigeru
     Yoshida]

  Cleanups:
   - Move fbdev drivers from strlcpy to strscpy [Wolfram Sang]
   - Indenting fixes, comment fixes, ... [Jiapeng Chong & Jilin Yuan]"

* tag 'fbdev-for-6.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev:
  fbdev: fbcon: Properly revert changes when vc_resize() failed
  fbdev: Move fbdev drivers from strlcpy to strscpy
  fbdev: omap: Remove unnecessary print function dev_err()
  fbdev: chipsfb: Add missing pci_disable_device() in chipsfb_pci_init()
  fbdev: fbcon: Destroy mutex on freeing struct fb_info
  fbdev: radeon: Clean up some inconsistent indenting
  fbdev: sisfb: Clean up some inconsistent indenting
  fbdev: fb_pm2fb: Avoid potential divide by zero error
  fbdev: ssd1307fb: Fix repeated words in comments
  fbdev: omapfb: Fix tests for platform_get_irq() failure

2 years agoprovide arch_test_bit_acquire for architectures that define test_bit
Mikulas Patocka [Fri, 26 Aug 2022 20:43:51 +0000 (16:43 -0400)]
provide arch_test_bit_acquire for architectures that define test_bit

Some architectures define their own arch_test_bit and they also need
arch_test_bit_acquire, otherwise they won't compile.  We also clean up
the code by using the generic test_bit if that is equivalent to the
arch-specific version.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 8238b4579866 ("wait_on_bit: add an acquire memory barrier")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2 years agoperf stat: Capitalize topdown metrics' names
Zhengjun Xing [Thu, 25 Aug 2022 01:54:58 +0000 (09:54 +0800)]
perf stat: Capitalize topdown metrics' names

Capitalize topdown metrics' names to follow the intel SDM.

Before:

 # ./perf stat -a  sleep 1

 Performance counter stats for 'system wide':

        228,094.05 msec cpu-clock                        #  225.026 CPUs utilized
               842      context-switches                 #    3.691 /sec
               224      cpu-migrations                   #    0.982 /sec
                70      page-faults                      #    0.307 /sec
        23,164,105      cycles                           #    0.000 GHz
        29,403,446      instructions                     #    1.27  insn per cycle
         5,268,185      branches                         #   23.097 K/sec
            33,239      branch-misses                    #    0.63% of all branches
       136,248,990      slots                            #  597.337 K/sec
        32,976,450      topdown-retiring                 #     24.2% retiring
         4,651,918      topdown-bad-spec                 #      3.4% bad speculation
        26,148,695      topdown-fe-bound                 #     19.2% frontend bound
        72,515,776      topdown-be-bound                 #     53.2% backend bound
         6,008,540      topdown-heavy-ops                #      4.4% heavy operations       #     19.8% light operations
         3,934,049      topdown-br-mispredict            #      2.9% branch mispredict      #      0.5% machine clears
        16,655,439      topdown-fetch-lat                #     12.2% fetch latency          #      7.0% fetch bandwidth
        41,635,972      topdown-mem-bound                #     30.5% memory bound           #     22.7% Core bound

       1.013634593 seconds time elapsed

After:

 # ./perf stat -a  sleep 1

 Performance counter stats for 'system wide':

        228,081.94 msec cpu-clock                        #  225.003 CPUs utilized
               824      context-switches                 #    3.613 /sec
               224      cpu-migrations                   #    0.982 /sec
                67      page-faults                      #    0.294 /sec
        22,647,423      cycles                           #    0.000 GHz
        28,870,551      instructions                     #    1.27  insn per cycle
         5,167,099      branches                         #   22.655 K/sec
            32,383      branch-misses                    #    0.63% of all branches
       133,411,074      slots                            #  584.926 K/sec
        32,352,607      topdown-retiring                 #     24.3% Retiring
         4,456,977      topdown-bad-spec                 #      3.3% Bad Speculation
        25,626,487      topdown-fe-bound                 #     19.2% Frontend Bound
        70,955,316      topdown-be-bound                 #     53.2% Backend Bound
         5,834,844      topdown-heavy-ops                #      4.4% Heavy Operations       #     19.9% Light Operations
         3,738,781      topdown-br-mispredict            #      2.8% Branch Mispredict      #      0.5% Machine Clears
        16,286,803      topdown-fetch-lat                #     12.2% Fetch Latency          #      7.0% Fetch Bandwidth
        40,802,069      topdown-mem-bound                #     30.6% Memory Bound           #     22.6% Core Bound

       1.013683125 seconds time elapsed

Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220825015458.3252239-1-zhengjun.xing@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2 years agoperf docs: Update the documentation for the save_type filter
Kan Liang [Tue, 16 Aug 2022 12:56:12 +0000 (05:56 -0700)]
perf docs: Update the documentation for the save_type filter

Update the documentation to reflect the kernel changes.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20220816125612.2042397-2-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2 years agoperf sched: Fix memory leaks in __cmd_record detected with -fsanitize=address
Ian Rogers [Wed, 24 Aug 2022 14:57:33 +0000 (07:57 -0700)]
perf sched: Fix memory leaks in __cmd_record detected with -fsanitize=address

An array of strings is passed to cmd_record but not freed. As
cmd_record modifies the array, add another array as a copy that can be
mutated allowing the original array contents to all be freed.

Detected with -fsanitize=address.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20220824145733.409005-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2 years agoperf record: Fix manpage formatting of description of support to hybrid systems
Andi Kleen [Thu, 18 Aug 2022 10:01:27 +0000 (03:01 -0700)]
perf record: Fix manpage formatting of description of support to hybrid systems

The Intel hybrid description is written in a different style than the
rest of the perf record man page. There were some new command line
options added after it which resulted in very strange section ordering.
Move the hybrid include last.

Also the sub sections in the hybrid document don't fit the record
manpage well (especially since it talks about all kinds of unrelated
commands). I left this for now, but would be better to separate this
properly in the different man pages.

It would be better to use sub sections for the other sections, but these
don't seem to be supported in AsciiDoc?

Some of the examples are still misrendered in the manpage with an
indented troff command, but I don't know how to fix that.

In any case it's now better than before.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: zhengjun.xing@intel.com
Link: https://lore.kernel.org/r/20220818100127.249401-1-ak@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2 years agoperf test: Stat test for repeat with a weak group
Ian Rogers [Mon, 22 Aug 2022 21:33:52 +0000 (14:33 -0700)]
perf test: Stat test for repeat with a weak group

Breaking a weak group requires multiple passes of an evlist, with
multiple runs this can introduce bugs ultimately leading to
segfaults. Add a test to cover this.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20220822213352.75721-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2 years agoperf stat: Clear evsel->reset_group for each stat run
Ian Rogers [Mon, 22 Aug 2022 21:33:51 +0000 (14:33 -0700)]
perf stat: Clear evsel->reset_group for each stat run

If a weak group is broken then the reset_group flag remains set for
the next run. Having reset_group set means the counter isn't created
and ultimately a segfault.

A simple reproduction of this is:

  # perf stat -r2 -e '{cycles,cycles,cycles,cycles,cycles,cycles,cycles,cycles,cycles,cycles}:W

which will be added as a test in the next patch.

Fixes: 4804e0111662d7d8 ("perf stat: Use affinity for opening events")
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20220822213352.75721-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2 years agotools kvm headers arm64: Update KVM header from the kernel sources
Arnaldo Carvalho de Melo [Mon, 21 Dec 2020 15:53:44 +0000 (12:53 -0300)]
tools kvm headers arm64: Update KVM header from the kernel sources

To pick the changes from:

  ae3b1da95413614f ("KVM: arm64: Fix compile error due to sign extension")

That doesn't result in any changes in tooling (when built on x86), only
addresses this perf build warning:

  Warning: Kernel ABI header at 'tools/arch/arm64/include/uapi/asm/kvm.h' differs from latest version at 'arch/arm64/include/uapi/asm/kvm.h'
  diff -u tools/arch/arm64/include/uapi/asm/kvm.h arch/arm64/include/uapi/asm/kvm.h

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/all/YwOMCCc4E79FuvDe@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2 years agoperf python: Fix build when PYTHON_CONFIG is user supplied
James Clark [Thu, 28 Jul 2022 09:39:46 +0000 (10:39 +0100)]
perf python: Fix build when PYTHON_CONFIG is user supplied

The previous change to Python autodetection had a small mistake where
the auto value was used to determine the Python binary, rather than the
user supplied value. The Python binary is only used for one part of the
build process, rather than the final linking, so it was producing
correct builds in most scenarios, especially when the auto detected
value matched what the user wanted, or the system only had a valid set
of Pythons.

Change it so that the Python binary path is derived from either the
PYTHON_CONFIG value or PYTHON value, depending on what is specified by
the user. This was the original intention.

This error was spotted in a build failure an odd cross compilation
environment after commit 4c41cb46a732fe82 ("perf python: Prefer
python3") was merged.

Fixes: 630af16eee495f58 ("perf tools: Use Python devtools for version autodetection rather than runtime")
Signed-off-by: James Clark <james.clark@arm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220728093946.1337642-1-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2 years agoMerge branch 'thermal-core'
Rafael J. Wysocki [Sat, 27 Aug 2022 13:07:58 +0000 (15:07 +0200)]
Merge branch 'thermal-core'

Merge thermal control core fixes for 6.0-rc3:

 - Fix missing required property for thermal zone description (Daniel
   Lezcano).

 - Add missing export symbol for
   thermal_zone_device_register_with_trips() (Daniel Lezcano).

* thermal-core:
  dt-bindings: thermal: Fix missing required property
  thermal/core: Add missing EXPORT_SYMBOL_GPL

2 years agoMerge branch 'acpi-processor' into acpi
Rafael J. Wysocki [Sat, 27 Aug 2022 12:43:18 +0000 (14:43 +0200)]
Merge branch 'acpi-processor' into acpi

* acpi-processor:
  ACPI: processor: Remove freq Qos request for all CPUs

2 years agoperf/x86/intel/uncore: Fix broken read_counter() for SNB IMC PMU
Stephane Eranian [Wed, 3 Aug 2022 16:00:31 +0000 (09:00 -0700)]
perf/x86/intel/uncore: Fix broken read_counter() for SNB IMC PMU

Existing code was generating bogus counts for the SNB IMC bandwidth counters:

$ perf stat -a -I 1000 -e uncore_imc/data_reads/,uncore_imc/data_writes/
     1.000327813           1,024.03 MiB  uncore_imc/data_reads/
     1.000327813              20.73 MiB  uncore_imc/data_writes/
     2.000580153         261,120.00 MiB  uncore_imc/data_reads/
     2.000580153              23.28 MiB  uncore_imc/data_writes/

The problem was introduced by commit:
  07ce734dd8ad ("perf/x86/intel/uncore: Clean up client IMC")

Where the read_counter callback was replace to point to the generic
uncore_mmio_read_counter() function.

The SNB IMC counters are freerunnig 32-bit counters laid out contiguously in
MMIO. But uncore_mmio_read_counter() is using a readq() call to read from
MMIO therefore reading 64-bit from MMIO. Although this is okay for the
uncore_perf_event_update() function because it is shifting the value based
on the actual counter width to compute a delta, it is not okay for the
uncore_pmu_event_start() which is simply reading the counter  and therefore
priming the event->prev_count with a bogus value which is responsible for
causing bogus deltas in the perf stat command above.

The fix is to reintroduce the custom callback for read_counter for the SNB
IMC PMU and use readl() instead of readq(). With the change the output of
perf stat is back to normal:
$ perf stat -a -I 1000 -e uncore_imc/data_reads/,uncore_imc/data_writes/
     1.000120987             296.94 MiB  uncore_imc/data_reads/
     1.000120987             138.42 MiB  uncore_imc/data_writes/
     2.000403144             175.91 MiB  uncore_imc/data_reads/
     2.000403144              68.50 MiB  uncore_imc/data_writes/

Fixes: 07ce734dd8ad ("perf/x86/intel/uncore: Clean up client IMC")
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20220803160031.1379788-1-eranian@google.com
2 years agoMerge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Linus Torvalds [Fri, 26 Aug 2022 18:32:53 +0000 (11:32 -0700)]
Merge tag 'arm64-fixes' of git://git./linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "A bumper crop of arm64 fixes for -rc3.

  The largest change is fixing our parsing of the 'rodata=full' command
  line option, which kstrtobool() started treating as 'rodata=false'.
  The fix actually makes the parsing of that option much less fragile
  and updates the documentation at the same time.

  We still have a boot issue pending when KASLR is disabled at compile
  time, but there's a fresh fix on the list which I'll send next week if
  it holds up to testing.

  Summary:

   - Fix workaround for Cortex-A76 erratum #1286807

   - Add workaround for AMU erratum #2457168 on Cortex-A510

   - Drop reference to removed CONFIG_ARCH_RANDOM #define

   - Fix parsing of the "rodata=full" cmdline option

   - Fix a bunch of issues in the SME register state switching and sigframe code

   - Fix incorrect extraction of the CTR_EL0.CWG register field

   - Fix ACPI cache topology probing when the PPTT is not present

   - Trivial comment and whitespace fixes"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64/sme: Don't flush SVE register state when handling SME traps
  arm64/sme: Don't flush SVE register state when allocating SME storage
  arm64/signal: Flush FPSIMD register state when disabling streaming mode
  arm64/signal: Raise limit on stack frames
  arm64/cache: Fix cache_type_cwg() for register generation
  arm64/sysreg: Guard SYS_FIELD_ macros for asm
  arm64/sysreg: Directly include bitfield.h
  arm64: cacheinfo: Fix incorrect assignment of signed error value to unsigned fw_level
  arm64: errata: add detection for AMEVCNTR01 incrementing incorrectly
  arm64: fix rodata=full
  arm64: Fix comment typo
  docs/arm64: elf_hwcaps: unify newlines in HWCAP lists
  arm64: adjust KASLR relocation after ARCH_RANDOM removal
  arm64: Fix match_list for erratum 1286807 on Arm Cortex-A76

2 years agoMerge tag 'riscv-for-linus-6.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Fri, 26 Aug 2022 18:26:27 +0000 (11:26 -0700)]
Merge tag 'riscv-for-linus-6.0-rc3' of git://git./linux/kernel/git/riscv/linux

Pull RISC-V fixes from Palmer Dabbelt:

 - A handful of fixes for the Microchip device trees

 - A pair of fixes to eliminate build warnings

* tag 'riscv-for-linus-6.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: dts: microchip: mpfs: remove pci axi address translation property
  riscv: dts: microchip: mpfs: remove bogus card-detect-delay
  riscv: dts: microchip: mpfs: remove ti,fifo-depth property
  riscv: dts: microchip: mpfs: fix incorrect pcie child node name
  riscv: traps: add missing prototype
  riscv: signal: fix missing prototype warning
  riscv: dts: microchip: correct L2 cache interrupts

2 years agoMerge tag 'loongarch-fixes-6.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Fri, 26 Aug 2022 18:21:18 +0000 (11:21 -0700)]
Merge tag 'loongarch-fixes-6.0-1' of git://git./linux/kernel/git/chenhuacai/linux-loongson

Pull LoongArch fixes from Huacai Chen:
 "Fix a bunch of build errors/warnings, a poweroff error and an
  unbalanced locking in do_page_fault()"

* tag 'loongarch-fixes-6.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  LoongArch: mm: Avoid unnecessary page fault retires on shared memory types
  LoongArch: Add subword xchg/cmpxchg emulation
  LoongArch: Cleanup headers to avoid circular dependency
  LoongArch: Cleanup reset routines with new API
  LoongArch: Fix build warnings in VDSO
  LoongArch: Select PCI_QUIRKS to avoid build error

2 years agoMerge tag 'drm-fixes-2022-08-26-1' of git://anongit.freedesktop.org/drm/drm
Linus Torvalds [Fri, 26 Aug 2022 18:15:37 +0000 (11:15 -0700)]
Merge tag 'drm-fixes-2022-08-26-1' of git://anongit.freedesktop.org/drm/drm

Pull drm fixes from Dave Airlie:
 "Weekly fixes, lots of amdgpu fixes mostly for IP blocks introduced in
  6.0-rc1, otherwise vc4, nouveau fixes.

  gem:
   - Fix handle release leak

  nouveau:
   - Fix fencing when moving BO

  vc4:
   - HDMI fixes

  amdgpu:
   - GFX 11.0 fixes
   - PSP XGMI handling fixes
   - GFX9 fix for compute-only IPs
   - Drop duplicated function call
   - Fix warning due to missing header
   - NBIO 7.7 fixes
   - DCN 3.1.4 fixes
   - SDMA 6.0 fixes
   - SMU 13.0 fixes
   - Arcturus GPUVM page table fix
   - MMHUB 1.0 fix

  amdkfd:
   - GC 10.3.7 fix

  radeon:
   - Delayed work flush fix"

* tag 'drm-fixes-2022-08-26-1' of git://anongit.freedesktop.org/drm/drm: (21 commits)
  drm/amdgpu: mmVM_L2_CNTL3 register not initialized correctly
  drm/amdgpu: add MGCG perfmon setting for gfx11
  drm/amdkfd: Fix isa version for the GC 10.3.7
  drm/amdgpu: Fix page table setup on Arcturus
  drm/amd/pm: update SMU 13.0.0 driver_if header
  drm/amdgpu: add sdma instance check for gfx11 CGCG
  drm/amd/display: enable PCON support for dcn314
  drm/amdgpu: enable NBIO IP v7.7.0 Clock Gating
  drm/amdgpu: add NBIO IP v7.7.0 Clock Gating support
  drm/amdgpu: add TX_POWER_CTRL_1 macro definitions for NBIO IP v7.7.0
  nouveau: explicitly wait on the fence in nouveau_bo_move_m2mf
  drm/radeon: add a force flush to delay work when radeon
  drm/amd/display: Include missing header
  drm/amdgpu: Remove the additional kfd pre reset call for sriov
  drm/amdgpu: Check num_gfx_rings for gfx v9_0 rb setup.
  drm/amdgpu: fix hive reference leak when adding xgmi device
  drm/amdgpu: Move psp_xgmi_terminate call from amdgpu_xgmi_remove_device to psp_hw_fini
  drm/amdgpu: enable GFXOFF allow control for GC IP v11.0.1
  drm/gem: Fix GEM handle release errors
  drm/vc4: hdmi: Rework power up
  ...

2 years agoMerge tag 'block-6.0-2022-08-26' of git://git.kernel.dk/linux-block
Linus Torvalds [Fri, 26 Aug 2022 18:05:54 +0000 (11:05 -0700)]
Merge tag 'block-6.0-2022-08-26' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:

 - MD pull request via Song:
      - Fix for clustered raid (Guoqing Jiang)
      - req_op fix (Bart Van Assche)
      - Fix race condition in raid recreate (David Sloan)

 - loop configuration overflow fix (Siddh)

 - Fix missing commit_rqs call for certain conditions (Yu)

* tag 'block-6.0-2022-08-26' of git://git.kernel.dk/linux-block:
  md: call __md_stop_writes in md_stop
  Revert "md-raid: destroy the bitmap after destroying the thread"
  md: Flush workqueue md_rdev_misc_wq in md_alloc()
  md/raid10: Fix the data type of an r10_sync_page_io() argument
  loop: Check for overflow while configuring loop
  blk-mq: fix io hung due to missing commit_rqs

2 years agoMerge tag 'io_uring-6.0-2022-08-26' of git://git.kernel.dk/linux-block
Linus Torvalds [Fri, 26 Aug 2022 18:01:52 +0000 (11:01 -0700)]
Merge tag 'io_uring-6.0-2022-08-26' of git://git.kernel.dk/linux-block

Pull io_uring fixes from Jens Axboe:

 - Add missing header file to the MAINTAINERS entry for io_uring (Ammar)

 - liburing and the kernel ship the same io_uring.h header, but one
   change we've had for a long time only in liburing is to ensure it's
   C++ safe. Add extern C around it, so we can more easily sync them in
   the future (Ammar)

 - Fix an off-by-one in the sync cancel added in this merge window (me)

 - Error handling fix for passthrough (Kanchan)

 - Fix for address saving for async execution for the zc tx support
   (Pavel)

 - Fix ordering for TCP zc notifications, so we always have them ordered
   correctly between "data was sent" and "data was acked". This isn't
   strictly needed with the notification slots, but we've been pondering
   disabling the slot support for 6.0 - and if we do, then we do require
   the ordering to be sane. Regardless of that, it's the sane thing to
   do in terms of API (Pavel)

 - Minor cleanup for indentation and lockdep annotation (Pavel)

* tag 'io_uring-6.0-2022-08-26' of git://git.kernel.dk/linux-block:
  io_uring/net: save address for sendzc async execution
  io_uring: conditional ->async_data allocation
  io_uring/notif: order notif vs send CQEs
  io_uring/net: fix indentation
  io_uring/net: fix zc send link failing
  io_uring/net: fix must_hold annotation
  io_uring: fix submission-failure handling for uring-cmd
  io_uring: fix off-by-one in sync cancelation file check
  io_uring: uapi: Add `extern "C"` in io_uring.h for liburing
  MAINTAINERS: Add `include/linux/io_uring_types.h`

2 years agofbdev: fbcon: Properly revert changes when vc_resize() failed
Shigeru Yoshida [Thu, 18 Aug 2022 18:13:36 +0000 (03:13 +0900)]
fbdev: fbcon: Properly revert changes when vc_resize() failed

fbcon_do_set_font() calls vc_resize() when font size is changed.
However, if if vc_resize() failed, current implementation doesn't
revert changes for font size, and this causes inconsistent state.

syzbot reported unable to handle page fault due to this issue [1].
syzbot's repro uses fault injection which cause failure for memory
allocation, so vc_resize() failed.

This patch fixes this issue by properly revert changes for font
related date when vc_resize() failed.

Link: https://syzkaller.appspot.com/bug?id=3443d3a1fa6d964dd7310a0cb1696d165a3e07c4
Reported-by: syzbot+a168dbeaaa7778273c1b@syzkaller.appspotmail.com
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Signed-off-by: Helge Deller <deller@gmx.de>
CC: stable@vger.kernel.org # 5.15+