merge mm-hotfixes-stable into mm-nonmm-stable to pick up depended-upon changes

mm/mglru: reclaim offlined memcgs harder

In the effort to reduce zombie memcgs [1], it was discovered that the
memcg LRU doesn't apply enough pressure on offlined memcgs.  Specifically,
instead of rotating them to the tail of the current generation
(MEMCG_LRU_TAIL) for a second attempt, it moves them to the next
generation (MEMCG_LRU_YOUNG) after the first attempt.

Not applying enough pressure on offlined memcgs can cause them to build
up, and this can be particularly harmful to memory-constrained systems.

On Pixel 8 Pro, launching apps for 50 cycles:
                 Before  After  Change
  Zombie memcgs  45      35     -22%

[1] https://lore.kernel.org/CABdmKX2M6koq4Q0Cmp_-=wbP0Qa190HdEGGaHfxNS05gAkUtPA@mail.gmail.com/

Link: https://lkml.kernel.org/r/20231208061407.2125867-4-yuzhao@google.com
Fixes: e4dde56cd208 ("mm: multi-gen LRU: per-node lru_gen_folio lists")
Signed-off-by: Yu Zhao <yuzhao@google.com>
Reported-by: T.J. Mercier <tjmercier@google.com>
Tested-by: T.J. Mercier <tjmercier@google.com>
Cc: Charan Teja Kalla <quic_charante@quicinc.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Jaroslav Pulchart <jaroslav.pulchart@gooddata.com>
Cc: Kairui Song <ryncsn@gmail.com>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/mglru: respect min_ttl_ms with memcgs

While investigating kswapd "consuming 100% CPU" [1] (also see "mm/mglru:
try to stop at high watermarks"), it was discovered that the memcg LRU can
breach the thrashing protection imposed by min_ttl_ms.

Before the memcg LRU:
  kswapd()
    shrink_node_memcgs()
      mem_cgroup_iter()
        inc_max_seq()  // always hit a different memcg
    lru_gen_age_node()
      mem_cgroup_iter()
        check the timestamp of the oldest generation

After the memcg LRU:
  kswapd()
    shrink_many()
      restart:
        iterate the memcg LRU:
          inc_max_seq()  // occasionally hit the same memcg
          if raced with lru_gen_rotate_memcg():
            goto restart
    lru_gen_age_node()
      mem_cgroup_iter()
        check the timestamp of the oldest generation

Specifically, when the restart happens in shrink_many(), it needs to stick
with the (memcg LRU) generation it began with.  In other words, it should
neither re-read memcg_lru->seq nor age an lruvec of a different
generation.  Otherwise it can hit the same memcg multiple times without
giving lru_gen_age_node() a chance to check the timestamp of that memcg's
oldest generation (against min_ttl_ms).

[1] https://lore.kernel.org/CAK8fFZ4DY+GtBA40Pm7Nn5xCHy+51w3sfxPqkqpqakSXYyX+Wg@mail.gmail.com/

Link: https://lkml.kernel.org/r/20231208061407.2125867-3-yuzhao@google.com
Fixes: e4dde56cd208 ("mm: multi-gen LRU: per-node lru_gen_folio lists")
Signed-off-by: Yu Zhao <yuzhao@google.com>
Tested-by: T.J. Mercier <tjmercier@google.com>
Cc: Charan Teja Kalla <quic_charante@quicinc.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Jaroslav Pulchart <jaroslav.pulchart@gooddata.com>
Cc: Kairui Song <ryncsn@gmail.com>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/mglru: try to stop at high watermarks

The initial MGLRU patchset didn't include the memcg LRU support, and it
relied on should_abort_scan(), added by commit f76c83378851 ("mm:
multi-gen LRU: optimize multiple memcgs"), to "backoff to avoid
overshooting their aggregate reclaim target by too much".

Later on when the memcg LRU was added, should_abort_scan() was deemed
unnecessary, and the test results [1] showed no side effects after it was
removed by commit a579086c99ed ("mm: multi-gen LRU: remove eviction
fairness safeguard").

However, that test used memory.reclaim, which sets nr_to_reclaim to
SWAP_CLUSTER_MAX.  So it can overshoot only by SWAP_CLUSTER_MAX-1 pages,
i.e., from nr_reclaimed=nr_to_reclaim-1 to
nr_reclaimed=nr_to_reclaim+SWAP_CLUSTER_MAX-1.  Compared with the batch
size kswapd sets to nr_to_reclaim, SWAP_CLUSTER_MAX is tiny.  Therefore
that test isn't able to reproduce the worst case scenario, i.e., kswapd
overshooting GBs on large systems and "consuming 100% CPU" (see the Closes
tag).

Bring back a simplified version of should_abort_scan() on top of the memcg
LRU, so that kswapd stops when all eligible zones are above their
respective high watermarks plus a small delta to lower the chance of
KSWAPD_HIGH_WMARK_HIT_QUICKLY.  Note that this only applies to order-0
reclaim, meaning compaction-induced reclaim can still run wild (which is a
different problem).

On Android, launching 55 apps sequentially:
           Before     After      Change
  pgpgin   838377172  802955040  -4%
  pgpgout  38037080   34336300   -10%

[1] https://lore.kernel.org/20221222041905.2431096-1-yuzhao@google.com/

Link: https://lkml.kernel.org/r/20231208061407.2125867-2-yuzhao@google.com
Fixes: a579086c99ed ("mm: multi-gen LRU: remove eviction fairness safeguard")
Signed-off-by: Yu Zhao <yuzhao@google.com>
Reported-by: Charan Teja Kalla <quic_charante@quicinc.com>
Reported-by: Jaroslav Pulchart <jaroslav.pulchart@gooddata.com>
Closes: https://lore.kernel.org/CAK8fFZ4DY+GtBA40Pm7Nn5xCHy+51w3sfxPqkqpqakSXYyX+Wg@mail.gmail.com/
Tested-by: Jaroslav Pulchart <jaroslav.pulchart@gooddata.com>
Tested-by: Kalesh Singh <kaleshsingh@google.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Kairui Song <ryncsn@gmail.com>
Cc: T.J. Mercier <tjmercier@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/mglru: fix underprotected page cache

Unmapped folios accessed through file descriptors can be underprotected.
Those folios are added to the oldest generation based on:

1. The fact that they are less costly to reclaim (no need to walk the
   rmap and flush the TLB) and have less impact on performance (don't
   cause major PFs and can be non-blocking if needed again).
2. The observation that they are likely to be single-use. E.g., for
   client use cases like Android, its apps parse configuration files
   and store the data in heap (anon); for server use cases like MySQL,
   it reads from InnoDB files and holds the cached data for tables in
   buffer pools (anon).

However, the oldest generation can be very short lived, and if so, it
doesn't provide the PID controller with enough time to respond to a surge
of refaults.  (Note that the PID controller uses weighted refaults and
those from evicted generations only take a half of the whole weight.) In
other words, for a short lived generation, the moving average smooths out
the spike quickly.

To fix the problem:
1. For folios that are already on LRU, if they can be beyond the
   tracking range of tiers, i.e., five accesses through file
   descriptors, move them to the second oldest generation to give them
   more time to age. (Note that tiers are used by the PID controller
   to statistically determine whether folios accessed multiple times
   through file descriptors are worth protecting.)
2. When adding unmapped folios to LRU, adjust the placement of them so
   that they are not too close to the tail. The effect of this is
   similar to the above.

On Android, launching 55 apps sequentially:
                           Before     After      Change
  workingset_refault_anon  25641024   25598972   0%
  workingset_refault_file  115016834  106178438  -8%

Link: https://lkml.kernel.org/r/20231208061407.2125867-1-yuzhao@google.com
Fixes: ac35a4902374 ("mm: multi-gen LRU: minimal implementation")
Signed-off-by: Yu Zhao <yuzhao@google.com>
Reported-by: Charan Teja Kalla <quic_charante@quicinc.com>
Tested-by: Kalesh Singh <kaleshsingh@google.com>
Cc: T.J. Mercier <tjmercier@google.com>
Cc: Kairui Song <ryncsn@gmail.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Jaroslav Pulchart <jaroslav.pulchart@gooddata.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/shmem: fix race in shmem_undo_range w/THP

Split folios during the second loop of shmem_undo_range.  It's not
sufficient to only split folios when dealing with partial pages, since
it's possible for a THP to be faulted in after that point.  Calling
truncate_inode_folio in that situation can result in throwing away data
outside of the range being targeted.

[akpm@linux-foundation.org: tidy up comment layout]
Link: https://lkml.kernel.org/r/20230418084031.3439795-1-stevensd@google.com
Fixes: b9a8a4195c7d ("truncate,shmem: Handle truncates that split large folios")
Signed-off-by: David Stevens <stevensd@chromium.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Suleiman Souhlal <suleiman@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Revert "selftests: error out if kernel header files are not yet built"

This reverts commit 9fc96c7c19df ("selftests: error out if kernel header
files are not yet built").

It turns out that requiring the kernel headers to be built as a
prerequisite to building selftests, does not work in many cases. For
example, Peter Zijlstra writes:

"My biggest beef with the whole thing is that I simply do not want to use
'make headers', it doesn't work for me.

I have a ton of output directories and I don't care to build tools into
the output dirs, in fact some of them flat out refuse to work that way
(bpf comes to mind)." [1]

Therefore, stop erroring out on the selftests build. Additional patches
will be required in order to change over to not requiring the kernel
headers.

[1] https://lore.kernel.org/20231208221007.GO28727@noisy.programming.kicks-ass.net

Link: https://lkml.kernel.org/r/20231209020144.244759-1-jhubbard@nvidia.com
Fixes: 9fc96c7c19df ("selftests: error out if kernel header files are not yet built")
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Marcos Paulo de Souza <mpdesouza@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

crash_core: fix the check for whether crashkernel is from high memory

If crash_base is equal to CRASH_ADDR_LOW_MAX, it also indicates that
the crashkernel memory is allocated from high memory. However, the
current check only considers the case where crash_base is greater than
CRASH_ADDR_LOW_MAX. Fix it.

The runtime effects is that crashkernel high memory is successfully
reserved, whereas the crashkernel low memory is bypassed in this case,
then kdump kernel bootup will fail because of no low memory under 4G.

This patch also includes some minor cleanups.

Link: https://lkml.kernel.org/r/20231209141438.77233-1-ytcoode@gmail.com
Fixes: 0ab97169aa05 ("crash_core: add generic function to do reservation")
Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Zhen Lei <thunder.leizhen@huawei.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

x86, kexec: fix the wrong ifdeffery CONFIG_KEXEC

With the current ifdeffery CONFIG_KEXEC, get_cmdline_acpi_rsdp() is only
available when kexec_load interface is taken, while kexec_file_load
interface can't make use of it.

Now change it to CONFIG_KEXEC_CORE.

Link: https://lkml.kernel.org/r/20231208073036.7884-6-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Eric DeVolder <eric_devolder@yahoo.com>
Cc: Ignat Korchagin <ignat@cloudflare.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

sh, kexec: fix the incorrect ifdeffery and dependency of CONFIG_KEXEC

The select of KEXEC for CRASH_DUMP in kernel/Kconfig.kexec will be
dropped, then compiling errors will be triggered if below config
items are set:

===
CONFIG_CRASH_CORE=y
CONFIG_KEXEC_CORE=y
CONFIG_CRASH_DUMP=y
===

Here, change the dependency of building kexec_core related object files,
and the ifdeffery on SuperH from CONFIG_KEXEC to CONFIG_KEXEC_CORE.

Link: https://lkml.kernel.org/r/20231208073036.7884-5-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Eric DeVolder <eric_devolder@yahoo.com>
Cc: Ignat Korchagin <ignat@cloudflare.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips, kexec: fix the incorrect ifdeffery and dependency of CONFIG_KEXEC

The select of KEXEC for CRASH_DUMP in kernel/Kconfig.kexec will be
dropped, then compiling errors will be triggered if below config items are
set:

===
CONFIG_CRASH_CORE=y
CONFIG_KEXEC_CORE=y
CONFIG_CRASH_DUMP=y
===

--------------------------------------------------------------------
mipsel-linux-ld: kernel/kexec_core.o: in function `kimage_free':
kernel/kexec_core.c:(.text+0x2200): undefined reference to `machine_kexec_cleanup'
mipsel-linux-ld: kernel/kexec_core.o: in function `__crash_kexec':
kernel/kexec_core.c:(.text+0x2480): undefined reference to `machine_crash_shutdown'
mipsel-linux-ld: kernel/kexec_core.c:(.text+0x2488): undefined reference to `machine_kexec'
mipsel-linux-ld: kernel/kexec_core.o: in function `kernel_kexec':
kernel/kexec_core.c:(.text+0x29b8): undefined reference to `machine_shutdown'
mipsel-linux-ld: kernel/kexec_core.c:(.text+0x29c0): undefined reference to `machine_kexec'
--------------------------------------------------------------------

Here, change the dependency of building kexec_core related object files,
and the ifdeffery in mips from CONFIG_KEXEC to CONFIG_KEXEC_CORE.

Link: https://lkml.kernel.org/r/20231208073036.7884-4-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202311302042.sn8cDPIX-lkp@intel.com/
Cc: Eric DeVolder <eric_devolder@yahoo.com>
Cc: Ignat Korchagin <ignat@cloudflare.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

m68k, kexec: fix the incorrect ifdeffery and build dependency of CONFIG_KEXEC

The select of KEXEC for CRASH_DUMP in kernel/Kconfig.kexec will be
dropped, then compiling errors will be triggered if below config items are
set:

===
CONFIG_CRASH_CORE=y
CONFIG_KEXEC_CORE=y
CONFIG_CRASH_DUMP=y
===

Here, change the dependency of buinding machine_kexec.o relocate_kernel.o
and the ifdeffery in asm/kexe.h to CONFIG_KEXEC_CORE.

Link: https://lkml.kernel.org/r/20231208073036.7884-3-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Eric DeVolder <eric_devolder@yahoo.com>
Cc: Ignat Korchagin <ignat@cloudflare.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

loongarch, kexec: change dependency of object files

Patch series "kexec: fix the incorrect ifdeffery and dependency of
CONFIG_KEXEC".

The select of KEXEC for CRASH_DUMP in kernel/Kconfig.kexec will be
dropped, then compiling errors will be triggered if below config items are
set:

===
CONFIG_CRASH_CORE=y
CONFIG_KEXEC_CORE=y
CONFIG_CRASH_DUMP=y
===

E.g on mips, below link error are seen:
--------------------------------------------------------------------
mipsel-linux-ld: kernel/kexec_core.o: in function `kimage_free':
kernel/kexec_core.c:(.text+0x2200): undefined reference to `machine_kexec_cleanup'
mipsel-linux-ld: kernel/kexec_core.o: in function `__crash_kexec':
kernel/kexec_core.c:(.text+0x2480): undefined reference to `machine_crash_shutdown'
mipsel-linux-ld: kernel/kexec_core.c:(.text+0x2488): undefined reference to `machine_kexec'
mipsel-linux-ld: kernel/kexec_core.o: in function `kernel_kexec':
kernel/kexec_core.c:(.text+0x29b8): undefined reference to `machine_shutdown'
mipsel-linux-ld: kernel/kexec_core.c:(.text+0x29c0): undefined reference to `machine_kexec'
--------------------------------------------------------------------

Here, change the incorrect dependency of building kexec_core related
object files, and the ifdeffery on architectures from CONFIG_KEXEC to
CONFIG_KEXEC_CORE.

Testing:
========
Passed on mips and loognarch with the LKP reproducer.

This patch (of 5):

Currently, in arch/loongarch/kernel/Makefile, building machine_kexec.o
relocate_kernel.o depends on CONFIG_KEXEC.

Whereas, since we will drop the select of KEXEC for CRASH_DUMP in
kernel/Kconfig.kexec, compiling error will be triggered if below config
items are set:

===
CONFIG_CRASH_CORE=y
CONFIG_KEXEC_CORE=y
CONFIG_CRASH_DUMP=y
===

---------------------------------------------------------------
loongarch64-linux-ld: kernel/kexec_core.o: in function `.L209':
>> kexec_core.c:(.text+0x1660): undefined reference to `machine_kexec_cleanup'
   loongarch64-linux-ld: kernel/kexec_core.o: in function `.L287':
>> kexec_core.c:(.text+0x1c5c): undefined reference to `machine_crash_shutdown'
>> loongarch64-linux-ld: kexec_core.c:(.text+0x1c64): undefined reference to `machine_kexec'
   loongarch64-linux-ld: kernel/kexec_core.o: in function `.L2^B5':
>> kexec_core.c:(.text+0x2090): undefined reference to `machine_shutdown'
   loongarch64-linux-ld: kexec_core.c:(.text+0x20a0): undefined reference to `machine_kexec'
---------------------------------------------------------------

Here, change the dependency of machine_kexec.o relocate_kernel.o to
CONFIG_KEXEC_CORE can fix above building error.

Link: https://lkml.kernel.org/r/20231208073036.7884-1-bhe@redhat.com
Link: https://lkml.kernel.org/r/20231208073036.7884-2-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202311300946.kHE9Iu71-lkp@intel.com/
Cc: Eric DeVolder <eric_devolder@yahoo.com>
Cc: Ignat Korchagin <ignat@cloudflare.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/damon/core: make damon_start() waits until kdamond_fn() starts

The cleanup tasks of kdamond threads including reset of corresponding
DAMON context's ->kdamond field and decrease of global nr_running_ctxs
counter is supposed to be executed by kdamond_fn().  However, commit
0f91d13366a4 ("mm/damon: simplify stop mechanism") made neither
damon_start() nor damon_stop() ensure the corresponding kdamond has
started the execution of kdamond_fn().

As a result, the cleanup can be skipped if damon_stop() is called fast
enough after the previous damon_start().  Especially the skipped reset
of ->kdamond could cause a use-after-free.

Fix it by waiting for start of kdamond_fn() execution from
damon_start().

Link: https://lkml.kernel.org/r/20231208175018.63880-1-sj@kernel.org
Fixes: 0f91d13366a4 ("mm/damon: simplify stop mechanism")
Signed-off-by: SeongJae Park <sj@kernel.org>
Reported-by: Jakub Acs <acsjakub@amazon.de>
Cc: Changbin Du <changbin.du@intel.com>
Cc: Jakub Acs <acsjakub@amazon.de>
Cc: <stable@vger.kernel.org> # 5.15.x
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

selftests/mm: cow: print ksft header before printing anything else

Doing a ksft_print_msg() before the ksft_print_header() seems to confuse
the ksft framework in a strange way: running the test on the cmdline
results in the expected output.

But piping the output somewhere else, results in some odd output,
whereby we repeatedly get the same info printed:
# [INFO] detected THP size: 2048 KiB
# [INFO] detected hugetlb page size: 2048 KiB
# [INFO] detected hugetlb page size: 1048576 KiB
# [INFO] huge zeropage is enabled
TAP version 13
1..190
# [INFO] Anonymous memory tests in private mappings
# [RUN] Basic COW after fork() ... with base page
# [INFO] detected THP size: 2048 KiB
# [INFO] detected hugetlb page size: 2048 KiB
# [INFO] detected hugetlb page size: 1048576 KiB
# [INFO] huge zeropage is enabled
TAP version 13
1..190
# [INFO] Anonymous memory tests in private mappings
# [RUN] Basic COW after fork() ... with base page
ok 1 No leak from parent into child
# [RUN] Basic COW after fork() ... with swapped out base page
# [INFO] detected THP size: 2048 KiB
# [INFO] detected hugetlb page size: 2048 KiB
# [INFO] detected hugetlb page size: 1048576 KiB
# [INFO] huge zeropage is enabled

Doing the ksft_print_header() first seems to resolve that and gives us
the output we expect:
TAP version 13
# [INFO] detected THP size: 2048 KiB
# [INFO] detected hugetlb page size: 2048 KiB
# [INFO] detected hugetlb page size: 1048576 KiB
# [INFO] huge zeropage is enabled
1..190
# [INFO] Anonymous memory tests in private mappings
# [RUN] Basic COW after fork() ... with base page
ok 1 No leak from parent into child
# [RUN] Basic COW after fork() ... with swapped out base page
ok 2 No leak from parent into child
# [RUN] Basic COW after fork() ... with THP
ok 3 No leak from parent into child
# [RUN] Basic COW after fork() ... with swapped-out THP
ok 4 No leak from parent into child
# [RUN] Basic COW after fork() ... with PTE-mapped THP
ok 5 No leak from parent into child

Link: https://lkml.kernel.org/r/20231206103558.38040-1-david@redhat.com
Fixes: f4b5fd6946e2 ("selftests/vm: anon_cow: THP tests")
Signed-off-by: David Hildenbrand <david@redhat.com>
Reported-by: Nico Pache <npache@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: fix VMA heap bounds checking

After converting selinux to VMA heap check helper, the gcl triggers an
execheap SELinux denial, which is caused by a changed logic check.

Previously selinux only checked that the VMA range was within the VMA heap
range, and the implementation checks the intersection between the two
ranges, but the corner case (vm_end=start_brk, brk=vm_start) isn't handled
correctly.

Since commit 11250fd12eb8 ("mm: factor out VMA stack and heap checks") was
only a function extraction, it seems that the issue was introduced by
commit 0db0c01b53a1 ("procfs: fix /proc/<pid>/maps heap check").  Let's
fix above corner cases, meanwhile, correct the wrong indentation of the
stack and heap check helpers.

Fixes: 11250fd12eb8 ("mm: factor out VMA stack and heap checks")
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reported-by: Ondrej Mosnacek <omosnace@redhat.com>
Closes: https://lore.kernel.org/selinux/CAFqZXNv0SVT0fkOK6neP9AXbj3nxJ61JAY4+zJzvxqJaeuhbFw@mail.gmail.com/
Tested-by: Ondrej Mosnacek <omosnace@redhat.com>
Link: https://lkml.kernel.org/r/20231207152525.2607420-1-wangkefeng.wang@huawei.com
Cc: David Hildenbrand <david@redhat.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

riscv: fix VMALLOC_START definition

When below config items are set, compiler complained:

--------------------
CONFIG_CRASH_CORE=y
CONFIG_KEXEC_CORE=y
CONFIG_CRASH_DUMP=y
......
-----------------------

-------------------------------------------------------------------
arch/riscv/kernel/crash_core.c: In function 'arch_crash_save_vmcoreinfo':
arch/riscv/kernel/crash_core.c:11:58: warning: format '%lx' expects argument of type 'long unsigned int', but argument 2 has type 'int' [-Wformat=]
11 |         vmcoreinfo_append_str("NUMBER(VMALLOC_START)=0x%lx\n", VMALLOC_START);
   |                                                        ~~^
   |                                                          |
   |                                                          long unsigned int
   |                                                        %x
----------------------------------------------------------------------

This is because on riscv macro VMALLOC_START has different type when
CONFIG_MMU is set or unset.

arch/riscv/include/asm/pgtable.h:
--------------------------------------------------

Changing it to _AC(0, UL) in case CONFIG_MMU=n can fix the warning.

Link: https://lkml.kernel.org/r/ZW7OsX4zQRA3mO4+@MiWiFi-R3L-srv
Signed-off-by: Baoquan He <bhe@redhat.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Cc: Eric DeVolder <eric_devolder@yahoo.com>
Cc: Ignat Korchagin <ignat@cloudflare.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kexec: drop dependency on ARCH_SUPPORTS_KEXEC from CRASH_DUMP

In commit f8ff23429c62 ("kernel/Kconfig.kexec: drop select of KEXEC for
CRASH_DUMP") we tried to fix a config regression, where CONFIG_CRASH_DUMP
required CONFIG_KEXEC.

However, it was not enough at least for arm64 platforms.  While further
testing the patch with our arm64 config I noticed that CONFIG_CRASH_DUMP
is unavailable in menuconfig.  This is because CONFIG_CRASH_DUMP still
depends on the new CONFIG_ARCH_SUPPORTS_KEXEC introduced in commit
91506f7e5d21 ("arm64/kexec: refactor for kernel/Kconfig.kexec") and on
arm64 CONFIG_ARCH_SUPPORTS_KEXEC requires CONFIG_PM_SLEEP_SMP=y, which in
turn requires either CONFIG_SUSPEND=y or CONFIG_HIBERNATION=y neither of
which are set in our config.

Given that we already established that CONFIG_KEXEC (which is a switch for
kexec system call itself) is not required for CONFIG_CRASH_DUMP drop
CONFIG_ARCH_SUPPORTS_KEXEC dependency as well.  The arm64 kernel builds
just fine with CONFIG_CRASH_DUMP=y and with both CONFIG_KEXEC=n and
CONFIG_KEXEC_FILE=n after f8ff23429c62 ("kernel/Kconfig.kexec: drop select
of KEXEC for CRASH_DUMP") and this patch are applied given that the
necessary shared bits are included via CONFIG_KEXEC_CORE dependency.

[bhe@redhat.com: don't export some symbols when CONFIG_MMU=n]
Link: https://lkml.kernel.org/r/ZW03ODUKGGhP1ZGU@MiWiFi-R3L-srv
[bhe@redhat.com: riscv, kexec: fix dependency of two items]
Link: https://lkml.kernel.org/r/ZW04G/SKnhbE5mnX@MiWiFi-R3L-srv
Link: https://lkml.kernel.org/r/20231129220409.55006-1-ignat@cloudflare.com
Fixes: 91506f7e5d21 ("arm64/kexec: refactor for kernel/Kconfig.kexec")
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: <stable@vger.kernel.org> # 6.6+: f8ff234: kernel/Kconfig.kexec: drop select of KEXEC for CRASH_DUMP
Cc: <stable@vger.kernel.org> # 6.6+
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

scripts/gdb: remove exception handling and refine print format

1. When we crash on a page, we want to check what happened on this
   page instead of skipping this page by try-except block.  Thus, removing
   the try-except block.

2. Remove redundant comma and print the task name properly.

Link: https://lkml.kernel.org/r/20231127070404.4192-4-Kuan-Ying.Lee@mediatek.com
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Qun-Wei Lin <qun-wei.lin@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

scripts/gdb/stackdepot: rename pool_index to pools_num

After stackdepot evicting support patchset[1], we rename pool_index to
pools_num.

To avoid from the below issue, we rename consistently in
gdb scripts.

Python Exception <class 'gdb.error'>: No symbol "pool_index" in current
context.
Error occurred in Python: No symbol "pool_index" in current context.

[1] https://lore.kernel.org/linux-mm/cover.1700502145.git.andreyknvl@google.com/
Link: https://lkml.kernel.org/r/20231129065142.13375-3-Kuan-Ying.Lee@mediatek.com
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Qun-Wei Lin <qun-wei.lin@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_page_bug() to nilfs_folio_bug()

All callers have a folio now, so convert it.

Link: https://lkml.kernel.org/r/20231127143036.2425-18-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_prepare_chunk() and nilfs_commit_chunk() to folios

All callers now have a folio, so convert these two functions.
Saves one call to compound_head() in unlock_page().

[konishi.ryusuke: resolved conflicts in nilfs_{set_link,delete_entry}]
Link: https://lkml.kernel.org/r/20231127143036.2425-17-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_make_empty() to use a folio

Remove two calls to compound_head() and switch from kmap_atomic to
kmap_local.

Link: https://lkml.kernel.org/r/20231127143036.2425-16-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_empty_dir() to use a folio

Remove three calls to compound_head() by using the folio API.

Link: https://lkml.kernel.org/r/20231127143036.2425-15-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_add_link() to use a folio

Remove six calls to compound_head() by using the folio API.

Link: https://lkml.kernel.org/r/20231127143036.2425-14-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_rename() to use folios

This involves converting nilfs_find_entry(), nilfs_dotdot(),
nilfs_set_link(), nilfs_delete_entry() and nilfs_do_unlink() to use folios
as well.

[konishi.ryusuke: followed the change of page release helper call sites]
Link: https://lkml.kernel.org/r/20231127143036.2425-13-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_find_entry to use a folio

Use the new folio APIs to remove calls to compound_head().

[konishi.ryusuke: resolved a conflict due to style warning correction]
Link: https://lkml.kernel.org/r/20231127143036.2425-12-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_readdir to use a folio

Use the new folio APIs to remove calls to compound_head().

Link: https://lkml.kernel.org/r/20231127143036.2425-11-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: add nilfs_get_folio()

Convert nilfs_get_page() to be a wrapper.
Also convert nilfs_check_page() to nilfs_check_folio().

Link: https://lkml.kernel.org/r/20231127143036.2425-10-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: switch to kmap_local for directory handling

Match ext2 by using kmap_local() instead of kmap().  This is more
efficient.  Also use unmap_and_put_page() instead of duplicating it as a
nilfs function.

[konishi.ryusuke: followed the change of page release helper call sites]
Link: https://lkml.kernel.org/r/20231127143036.2425-9-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: pass the mapped address to nilfs_check_page()

Remove another use of page_address() as part of preparing for the kmap to
kmap_local transition.

Link: https://lkml.kernel.org/r/20231127143036.2425-8-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: return the mapped address from nilfs_get_page()

In prepartion for switching from kmap() to kmap_local(), return the kmap
address from nilfs_get_page() instead of having the caller look up
page_address().

[konishi.ryusuke: fixed a missing blank line after declaration]
Link: https://lkml.kernel.org/r/20231127143036.2425-7-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: remove page_address() from nilfs_delete_entry

In preparation for removing kmap from directory handling, mask the
directory entry pointer to discover the start address of the page.
Matches ext2.

Link: https://lkml.kernel.org/r/20231127143036.2425-6-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: remove page_address() from nilfs_add_link

In preparation for removing kmap from directory handling, use
offset_in_page() to calculate 'from'.  Matches ext2.

Link: https://lkml.kernel.org/r/20231127143036.2425-5-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: remove page_address() from nilfs_set_link

In preparation for removing kmap from directory handling, use
offset_in_page() to calculate 'from'.  Matches ext2.

Link: https://lkml.kernel.org/r/20231127143036.2425-4-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: eliminate staggered calls to kunmap in nilfs_rename

In nilfs_rename(), calls to nilfs_put_page() to release pages obtained
with nilfs_find_entry() or nilfs_dotdot() are alternated in the normal
path.

When replacing the kernel memory mapping method from kmap to
kmap_local_{page,folio}, this violates the constraint on the calling order
of kunmap_local().

Swap the order of nilfs_put_page calls where the kmap sections of multiple
pages overlap so that they are nested, allowing direct replacement of
nilfs_put_page() -> unmap_and_put_page().

Without this reordering, that replacement will cause a kernel WARNING in
kunmap_local_indexed() on architectures with high memory mapping.

Link: https://lkml.kernel.org/r/20231127143036.2425-3-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: move page release outside of nilfs_delete_entry and nilfs_set_link

Patch series "nilfs2: Folio conversions for directory paths".

This series applies page->folio conversions to nilfs2 directory
operations.  This reduces hidden compound_head() calls and also converts
deprecated kmap calls to kmap_local in the directory code.

Although nilfs2 does not yet support large folios, Matthew has done his
best here to include support for large folios, which will be needed for
devices with large block sizes.

This series corresponds to the second half of the original post [1], but
with two complementary patches inserted at the beginning and some
adjustments, to prevent a kmap_local constraint violation found during
testing with highmem mapping.

[1] https://lkml.kernel.org/r/20231106173903.1734114-1-willy@infradead.org

I have reviewed all changes and tested this for regular and small block
sizes, both on machines with and without highmem mapping.  No issues
found.

This patch (of 17):

In a few directory operations, the call to nilfs_put_page() for a page
obtained using nilfs_find_entry() or nilfs_dotdot() is hidden in
nilfs_set_link() and nilfs_delete_entry(), making it difficult to track
page release and preventing change of its call position.

By moving nilfs_put_page() out of these functions, this makes the page
get/put correspondence clearer and makes it easier to swap
nilfs_put_page() calls (and kunmap calls within them) when modifying
multiple directory entries simultaneously in nilfs_rename().

Also, update comments for nilfs_set_link() and nilfs_delete_entry() to
reflect changes in their behavior.

To make nilfs_put_page() visible from namei.c, this moves its definition
to nilfs.h and replaces existing equivalents to use it, but the exposure
of that definition is temporary and will be removed on a later kmap ->
kmap_local conversion.

Link: https://lkml.kernel.org/r/20231127143036.2425-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20231127143036.2425-2-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

softlockup: serialized softlockup's log

If multiple CPUs trigger softlockup at the same time with
'softlockup_all_cpu_backtrace=0', the softlockup's logs will appear
staggeredly in dmesg, which will affect the viewing of the logs for
developer.  Since the code path for outputting softlockup logs is not a
kernel hotspot and the performance requirements for the code are not
strict, locks are used to serialize the softlockup log output to improve
the readability of the logs.

Link: https://lkml.kernel.org/r/20231123084022.10302-1-lizhe.67@bytedance.com
Signed-off-by: Li Zhe <lizhe.67@bytedance.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Cc: Lecopzer Chen <lecopzer.chen@mediatek.com>
Cc: Pingfan Liu <kernelfans@gmail.com>
Cc: Zefan Li <lizefan.x@bytedance.com>
Cc: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kexec_file: load kernel at top of system RAM if required

Patch series "kexec_file: Load kernel at top of system RAM if required".

Justification:
==============

Kexec_load interface has been doing top down searching and loading
kernel/initrd/purgtory etc to prepare for kexec reboot.  In that way, the
benefits are that it avoids to consume and fragment limited low memory
which satisfy DMA buffer allocation and big chunk of continuous memory
during system init; and avoids to stir with BIOS/FW reserved or occupied
areas, or corner case handling/work around/quirk occupied areas when doing
system init.  By the way, the top-down searching and loading of kexec-ed
kernel is done in user space utility code.

For kexec_file loading, even if kexec_buf.top_down is 'true', it's simply
ignored.  It calls walk_system_ram_res() directly to go through all
resources of System RAM bottom up, to find an available memory region,
then call locate_mem_hole_callback() to allocate memory in that found
memory region from top to down.  This is not expected and inconsistent
with kexec_load.

Implementation
===============

In patch 1, introduce a new function walk_system_ram_res_rev() which is a
variant of walk_system_ram_res(), it walks through a list of all the
resources of System RAM in reversed order, i.e., from higher to lower.

In patch 2, check if kexec_buf.top_down is 'true' in
kexec_walk_resources(), if yes, call walk_system_ram_res_rev() to find
memory region of system RAM from top to down to load kernel/initrd etc.

Background information: ======================= And I ever tried this in
the past in a different way, please see below link.  In the post, I tried
to adjust struct sibling linking code, replace the the singly linked list
with list_head so that walk_system_ram_res_rev() can be implemented in a
much easier way.  Finally I failed.
https://lore.kernel.org/all/20180718024944.577-4-bhe@redhat.com/

This time, I picked up the patch from AKASHI Takahiro's old post and made
some change to take as the current patch 1:
https://lists.infradead.org/pipermail/linux-arm-kernel/2017-September/531456.html

This patch (of 2):

Kexec_load interface has been doing top down searching and loading
kernel/initrd/purgtory etc to prepare for kexec reboot.  In that way, the
benefits are that it avoids to consume and fragment limited low memory
which satisfy DMA buffer allocation and big chunk of continuous memory
during system init; and avoids to stir with BIOS/FW reserved or occupied
areas, or corner case handling/work around/quirk occupied areas when doing
system init.  By the way, the top-down searching and loading of kexec-ed
kernel is done in user space utility code.

For kexec_file loading, even if kexec_buf.top_down is 'true', it's simply
ignored.  It calls walk_system_ram_res() directly to go through all
resources of System RAM bottom up, to find an available memory region,
then call locate_mem_hole_callback() to allocate memory in that found
memory region from top to down.  This is not expected and inconsistent
with kexec_load.

Here check if kexec_buf.top_down is 'true' in kexec_walk_resources(), if
yes, call the newly added walk_system_ram_res_rev() to find memory region
of system RAM from top to down to load kernel/initrd etc.

Link: https://lkml.kernel.org/r/20231114091658.228030-1-bhe@redhat.com
Link: https://lkml.kernel.org/r/20231114091658.228030-3-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

resource: add walk_system_ram_res_rev()

This function, being a variant of walk_system_ram_res() introduced in
commit 8c86e70acead ("resource: provide new functions to walk through
resources"), walks through a list of all the resources of System RAM in
reversed order, i.e., from higher to lower.

It will be used in kexec_file code to load kernel, initrd etc when
preparing kexec reboot.

Link: https://lkml.kernel.org/r/ZVTA6z/06cLnWKUz@MiWiFi-R3L-srv
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

powerpc: pmd_move_must_withdraw() is only needed for CONFIG_TRANSPARENT_HUGEPAGE

This is required for the later patch "Makefile.extrawarn: turn on
missing-prototypes globally".

Link: https://lkml.kernel.org/r/20231127132809.45c2b398@canb.auug.org.au
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

usb: fsl-mph-dr-of: mark fsl_usb2_mpc5121_init() static

This function is only called locally and should always have been static:

drivers/usb/host/fsl-mph-dr-of.c:291:5: error: no previous prototype for 'fsl_usb2_mpc5121_init' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231123110506.707903-6-arnd@kernel.org
Fixes: 230f7ede6c2f ("USB: add USB EHCI support for MPC5121 SoC")
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Tudor Ambarus <tudor.ambarus@linaro.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

x86: sta2x11: include header for sta2x11_get_instance() prototype

sta2x11_get_instance() is a global function declared in asm/sta2x11.h, but
this header is not included before the definition, causing a warning:

arch/x86/pci/sta2x11-fixup.c:95:26: error: no previous prototype for 'sta2x11_get_instance' [-Werror=missing-prototypes]

Add the missing #include.

Link: https://lkml.kernel.org/r/20231123110506.707903-5-arnd@kernel.org
Fixes: 83125a3a189e ("x86, platform: Initial support for sta2x11 I/O hub")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Tudor Ambarus <tudor.ambarus@linaro.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

sched: fair: move unused stub functions to header

These four functions have a normal definition for CONFIG_FAIR_GROUP_SCHED,
and empty one that is only referenced when FAIR_GROUP_SCHED is disabled
but CGROUP_SCHED is still enabled.  If both are turned off, the functions
are still defined but the misisng prototype causes a W=1 warning:

kernel/sched/fair.c:12544:6: error: no previous prototype for 'free_fair_sched_group'
kernel/sched/fair.c:12546:5: error: no previous prototype for 'alloc_fair_sched_group'
kernel/sched/fair.c:12553:6: error: no previous prototype for 'online_fair_sched_group'
kernel/sched/fair.c:12555:6: error: no previous prototype for 'unregister_fair_sched_group'

Move the alternatives into the header as static inline functions with the
correct combination of #ifdef checks to avoid the warning without adding
even more complexity.

[A different patch with the same description got applied by accident
 and was later reverted, but the original patch is still missing]

Link: https://lkml.kernel.org/r/20231123110506.707903-4-arnd@kernel.org
Fixes: 7aa55f2a5902 ("sched/fair: Move unused stub functions to header")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Tudor Ambarus <tudor.ambarus@linaro.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

jffs2: mark __jffs2_dbg_superblock_counts() static

This function is only called locally and does not need to be global.
Since there is no external prototype, gcc warns about the non-static
definition:

fs/jffs2/debug.c:160:6: error: no previous prototype for '__jffs2_dbg_superblock_counts' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231123110506.707903-3-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

ida: make 'ida_dump' static

Patch series "Treewide: enable -Wmissing-prototypes", v3.

At this point, there are five architectures with a number of known
regressions: alpha, nios2, mips, sh and sparc.  In the previous version of
this patch, I had turned off the missing prototype warnings for the 15
architectures that still had issues, but since there are only five left, I
think we can leave the rest to the maintainers (Cc'd here) as well.

The series is also likely to cause occasional build regressions on
linux-next as developers add new code that misses prototypes.  Hopefully
this should be resolved by the time the patches make it into a release and
everyone gets the warnings right away.

This patch (of 6):

There is no global declaration for ida_dump() and no other callers, so
make it static to avoid this warning:

lib/test_ida.c:16:6: error: no previous prototype for 'ida_dump'

Link: https://lkml.kernel.org/r/20231123110506.707903-1-arnd@kernel.org
Link: https://lkml.kernel.org/r/20231123110506.707903-2-arnd@kernel.org
Fixes: 8ab8ba38d488 ("ida: Start new test_ida module")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Tudor Ambarus <tudor.ambarus@linaro.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Kees Cook <keescook@chromium.org>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: kexec: include linux/reboot.h

Two functions are provided for kexec, but the mips implementation is
missing the corresponding #include statment:

arch/mips/kernel/machine_kexec.c:136:1: error: no previous prototype for 'machine_shutdown' [-Werror=missing-prototypes]
arch/mips/kernel/machine_kexec.c:152:1: error: no previous prototype for 'machine_crash_shutdown' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-21-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: smp: fix setup_profiling_timer() prototype

The function is unconditionally defined in smp.c but is conditionally
declared in a header that is not included here.

arch/mips/kernel/smp.c:473:5: error: no previous prototype for 'setup_profiling_timer' [-Werror=missing-prototypes]

Add the missing #include and #ifdef to match the declaration.

Link: https://lkml.kernel.org/r/20231204115710.2247097-20-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: hide conditionally unused functions

A couple of functions are defined unconditionally but have a conditional
declaration:

arch/mips/mm/tlb-r4k.c:461:12: error: no previous prototype for 'add_temporary_entry' [-Werror=missing-prototypes]
arch/mips/mm/pgtable-64.c:92:7: error: no previous prototype for 'mk_pmd' [-Werror=missing-prototypes]
arch/mips/mm/pgtable-64.c:101:6: error: no previous prototype for 'set_pmd_at' [-Werror=missing-prototypes]

Since there are no callers in these configurations, add the same #ifdef
checks around the definitions.

Link: https://lkml.kernel.org/r/20231204115710.2247097-19-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: suspend: include linux/suspend.h as needed

A couple of functions are defined by the architecture and declared in
linux/suspend.h, but mips is lacking the corresponding #include statement
before the definition:

arch/mips/power/cpu.c:16:6: warning: no previous prototype for 'save_processor_state' [-Wmissing-prototypes]
arch/mips/power/cpu.c:26:6: warning: no previous prototype for 'restore_processor_state' [-Wmissing-prototypes]
arch/mips/power/cpu.c:36:5: warning: no previous prototype for 'pfn_is_nosave' [-Wmissing-prototypes]
arch/mips/power/hibernate.c:6:5: warning: no previous prototype for 'swsusp_arch_resume' [-Wmissing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-18-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: mt: include asm/mips_mt.h

These two functions have a global prototype but the header is not included
before the function definitions:

arch/mips/kernel/mips-mt.c:50:6: error: no previous prototype for 'mips_mt_regdump' [-Werror=missing-prototypes]
arch/mips/kernel/mips-mt.c:159:6: error: no previous prototype for 'mips_mt_set_cpuoptions' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-16-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: spram: fix missing prototype warning for spram_config

arch/mips/kernel/spram.c:194:6: error: no previous prototype for 'spram_config' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-15-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: add missing declarations

These are three more functions that are only called from assembler and
only need a declaration to avoid the -Wmissing-prototypes warnings:

arch/mips/kernel/signal.c:904:17: error: no previous prototype for 'do_notify_resume' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:370:6: error: no previous prototype for 'show_registers' [-Werror=missing-prototypes]
arch/mips/kernel/smp.c:352:17: error: no previous prototype for 'start_secondary' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-14-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: move cache declarations into header

Some of the cache functions are declared only for their callers, e.g.

arch/mips/mm/c-r3k.c:28:15: error: no previous prototype for 'r3k_cache_size' [-Werror=missing-prototypes]
arch/mips/mm/c-r3k.c:63:15: error: no previous prototype for 'r3k_cache_lsize' [-Werror=missing-prototypes]
arch/mips/mm/c-r4k.c:1703:6: error: no previous prototype for 'r4k_cache_init' [-Werror=missing-prototypes]
arch/mips/mm/sc-mips.c:255:5: error: no previous prototype for 'mips_sc_init' [-Werror=missing-prototypes]

Move all the declarations to asm/cache.h and asm/r4kcache.h where they
can be seen by the function definitions.

Link: https://lkml.kernel.org/r/20231204115710.2247097-13-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: fix tlb_init() prototype

There are two definitions for tlb_init(), but no global declaration:

arch/mips/mm/tlb-r4k.c:552:6: error: no previous prototype for 'tlb_init' [-Werror=missing-prototypes]
arch/mips/mm/tlb-r3k.c:244:6: error: no previous prototype for 'tlb_init' [-Werror=missing-prototypes]

Move the declaration to asm/setup.h and included it as needed.

Link: https://lkml.kernel.org/r/20231204115710.2247097-12-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: fix setup_zero_pages() prototype

setup_zero_pages() has a local declaration in a platform specific header,
but that is not seen in the file it is defined in:

arch/mips/mm/init.c:60:6: error: no previous prototype for 'setup_zero_pages' [-Werror=missing-prototypes]

Move it to the corresponding global header and include that where needed.

Link: https://lkml.kernel.org/r/20231204115710.2247097-11-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: unhide uasm_in_compat_space_p() declaration

uasm_in_compat_space_p() has a conditional declaration but is defined
unconditionally because of another local user, which causes a warning:

arch/mips/mm/uasm.c:421:5: error: no previous prototype for 'uasm_in_compat_space_p' [-Werror=missing-prototypes]

Make the declaration unconditional to avoid this.

Link: https://lkml.kernel.org/r/20231204115710.2247097-10-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: move jump_label_apply_nops() declaration to header

Instead of an extern declaration in the C file with the caller, move it to
an appropriate header, avoiding

arch/mips/kernel/jump_label.c:93:6: error: no previous prototype for 'jump_label_apply_nops' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-9-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: move build_tlb_refill_handler() prototype

Instead of having a declaration for each caller, have one that is shared
with the function definition, which avoids a warning:

arch/mips/mm/tlbex.c:2547:6: error: no previous prototype for 'build_tlb_refill_handler' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-8-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: mark local function static if possible

These two functions are global but have no extern prototypes or other
callers, so it's best to mark them as static, avoiding these warnings:

arch/mips/kernel/mips-cm.c:204:13: error: no previous prototype for '__mips_cm_l2sync_phys_base' [-Werror=missing-prototypes]
arch/mips/mm/c-r4k.c:1827:12: error: no previous prototype for 'r4k_cache_init_pm' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-7-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: signal: move sigcontext declarations to header

Function declarations should be in a shared header to ensure the
prototypes match the definition:

arch/mips/kernel/signal.c:439:5: error: no previous prototype for 'setup_sigcontext' [-Werror=missing-prototypes]
arch/mips/kernel/signal.c:516:5: error: no previous prototype for 'restore_sigcontext' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-6-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: rs870e: stop exporting local functions

These four functions are exported, but don't have any users, and no
prototypes, which now causes warnings:

drivers/platform/mips/rs780e-acpi.c:35:6: error: no previous prototype for 'pm_iowrite' [-Werror=missing-prototypes]
drivers/platform/mips/rs780e-acpi.c:41:4: error: no previous prototype for 'pm_ioread' [-Werror=missing-prototypes]
drivers/platform/mips/rs780e-acpi.c:47:6: error: no previous prototype for 'pm2_iowrite' [-Werror=missing-prototypes]
drivers/platform/mips/rs780e-acpi.c:53:4: error: no previous prototype for 'pm2_ioread' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-5-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: add missing declarations for trap handlers

These exception handlers are all called from assembly code, so they don't
normally need a declaration, but without one we now get warnings:

arch/mips/mm/fault.c:323:17: error: no previous prototype for 'do_page_fault' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:447:17: error: no previous prototype for 'do_be' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:752:17: error: no previous prototype for 'do_ov' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:874:17: error: no previous prototype for 'do_fpe' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1027:17: error: no previous prototype for 'do_bp' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1114:17: error: no previous prototype for 'do_tr' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1151:17: error: no previous prototype for 'do_ri' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1402:17: error: no previous prototype for 'do_cpu' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1507:17: error: no previous prototype for 'do_msa_fpe' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1527:17: error: no previous prototype for 'do_msa' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1548:17: error: no previous prototype for 'do_mdmx' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1560:17: error: no previous prototype for 'do_watch' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1587:17: error: no previous prototype for 'do_mcheck' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1612:17: error: no previous prototype for 'do_mt' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1648:17: error: no previous prototype for 'do_dsp' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1656:17: error: no previous prototype for 'do_reserved' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1832:17: error: no previous prototype for 'cache_parity_error' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1880:17: error: no previous prototype for 'do_ftlb' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1909:17: error: no previous prototype for 'do_gsexc' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1944:6: error: no previous prototype for 'ejtag_exception_handler' [-Werror=missing-prototypes]
arch/mips/kernel/traps.c:1989:17: error: no previous prototype for 'nmi_exception_handler' [-Werror=missing-prototypes]
arch/mips/kernel/unaligned.c:1516:17: error: no previous prototype for 'do_ade' [-Werror=missing-prototypes]

Link: https://lkml.kernel.org/r/20231204115710.2247097-4-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: add asm/syscalls.h header

System call prototypes are generally in linux/syscalls.h, but there are a
couple of mips specific entry points that are missing there:

arch/mips/kernel/signal.c:636:17: error: no previous prototype for 'sys_sigreturn' [-Werror=missing-prototypes]
arch/mips/kernel/signal.c:673:17: error: no previous prototype for 'sys_rt_sigreturn' [-Werror=missing-prototypes]
arch/mips/kernel/syscall.c:51:16: error: no previous prototype for 'sysm_pipe' [-Werror=missing-prototypes]
arch/mips/kernel/mips-mt-fpaff.c:65:17: error: no previous prototype for 'mipsmt_sys_sched_setaffinity' [-Werror=missing-prototypes]
arch/mips/kernel/mips-mt-fpaff.c:157:17: error: no previous prototype for 'mipsmt_sys_sched_getaffinity' [-Werror=missing-prototypes]

Add these to a new asm/syscalls.h as we have in other architectures.

Link: https://lkml.kernel.org/r/20231204115710.2247097-3-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mips: decompress: fix add missing prototypes

Patch series "mips: address -Wmissing-prototypes warnings".

Address the -Wmissing-prototypes warnings that showed up in mips as the
last major architecture after my patch to enable the option everywhere.

This patch (of 20):

The mips decompressor has some string functions defined locally that are
not declared in the right place:

arch/mips/boot/compressed/dbg.c:12:13: error: no previous prototype for 'putc' [-Werror=missing-prototypes]
arch/mips/boot/compressed/dbg.c:16:6: error: no previous prototype for 'puts' [-Werror=missing-prototypes]
arch/mips/boot/compressed/dbg.c:26:6: error: no previous prototype for 'puthex' [-Werror=missing-prototypes]
arch/mips/boot/compressed/string.c:11:7: error: no previous prototype for 'memcpy' [-Werror=missing-prototypes]
arch/mips/boot/compressed/string.c:22:7: error: no previous prototype for 'memset' [-Werror=missing-prototypes]
arch/mips/boot/compressed/string.c:32:15: error: no previous prototype for 'memmove' [-Werror=missing-prototypes]
arch/mips/boot/compressed/decompress.c:43:6: error: no previous prototype for 'error' [-Werror=missing-prototypes]
arch/mips/boot/compressed/decompress.c:91:6: error: no previous prototype for 'decompress_kernel' [-Werror=missing-prototypes]

Include the string.h header where needed and add a decompress.h header to
have shared prototypes for the rest.

Link: https://lkml.kernel.org/r/20231204115710.2247097-1-arnd@kernel.org
Link: https://lkml.kernel.org/r/20231204115710.2247097-2-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@rothwell.id.au>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

s390/traps: only define is_valid_bugaddr() under CONFIG_GENERIC_BUG

When building with -Wmissing-prototypes without CONFIG_GENERIC_BUG, there
is a warning about a missing prototype for is_valid_bugaddr():

  arch/s390/kernel/traps.c:46:5: warning: no previous prototype for 'is_valid_bugaddr' [-Wmissing-prototypes]
     46 | int is_valid_bugaddr(unsigned long addr)
        |     ^~~~~~~~~~~~~~~~

The prototype is only declared with CONFIG_GENERIC_BUG, so only define the
function under the same condition to clear up the warning, which matches
other architectures.

Link: https://lkml.kernel.org/r/20231130-s390-missing-prototypes-v1-2-799d3cf07fb7@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Jan Höppner <hoeppner@linux.ibm.com>
Cc: Stefan Haberland <sth@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

s390/dasd: remove dasd_stats_generic_show()

Patch series "s390: A couple of fixes for -Wmissing-prototypes".

This series resolves a couple of -Wmissing-prototypes that I see in my
builds of -next, even though the issues appear to be latent.  This
addresses issues which will be exposed by the later patch
"Makefile.extrawarn: turn on missing-prototypes globally".

This patch (of 2):

With CONFIG_DASD_PROFILE=n, there is a warning that
dasd_stats_generic_show() is missing a prototype:

  drivers/s390/block/dasd.c:1109:5: warning: no previous prototype for 'dasd_stats_generic_show' [-Wmissing-prototypes]
   1109 | int dasd_stats_generic_show(struct seq_file *m, void *v)
        |     ^~~~~~~~~~~~~~~~~~~~~~~

This function has been unused since its introduction in commit
4fa52aa7a82f ("[S390] dasd: add enhanced DASD statistics interface"),
remove it to clear up the warning.

Link: https://lkml.kernel.org/r/20231130-s390-missing-prototypes-v1-0-799d3cf07fb7@kernel.org
Link: https://lkml.kernel.org/r/20231130-s390-missing-prototypes-v1-1-799d3cf07fb7@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Jan Höppner <hoeppner@linux.ibm.com>
Cc: Stefan Haberland <sth@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: traps: add internal prototypes for functions only called from asm

Clang warns:

  arch/hexagon/kernel/traps.c:284:6: warning: no previous prototype for function 'do_genex' [-Wmissing-prototypes]
    284 | void do_genex(struct pt_regs *regs)
        |      ^
  arch/hexagon/kernel/traps.c:284:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    284 | void do_genex(struct pt_regs *regs)
        | ^
        | static
  arch/hexagon/kernel/traps.c:341:6: warning: no previous prototype for function 'do_trap0' [-Wmissing-prototypes]
    341 | void do_trap0(struct pt_regs *regs)
        |      ^
  arch/hexagon/kernel/traps.c:341:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    341 | void do_trap0(struct pt_regs *regs)
        | ^
        | static
  arch/hexagon/kernel/traps.c:418:6: warning: no previous prototype for function 'do_machcheck' [-Wmissing-prototypes]
    418 | void do_machcheck(struct pt_regs *regs)
        |      ^
  arch/hexagon/kernel/traps.c:418:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    418 | void do_machcheck(struct pt_regs *regs)
        | ^
        | static
  arch/hexagon/kernel/traps.c:428:6: warning: no previous prototype for function 'do_debug_exception' [-Wmissing-prototypes]
    428 | void do_debug_exception(struct pt_regs *regs)
        |      ^
  arch/hexagon/kernel/traps.c:428:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    428 | void do_debug_exception(struct pt_regs *regs)
        | ^
        | static

These functions are only called from assembly or this translation unit,
so just add prototypes right above the definitions to silence the
warnings.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-19-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: traps: remove sys_syscall()

Clang warns:

  arch/hexagon/kernel/traps.c:335:6: warning: no previous prototype for function 'sys_syscall' [-Wmissing-prototypes]
    335 | long sys_syscall(void)
        |      ^
  arch/hexagon/kernel/traps.c:335:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    335 | long sys_syscall(void)
        | ^
        | static

This function is not used anywhere, so remove it.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-18-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: irq: add prototype for arch_do_IRQ()

Clang warns:

  arch/hexagon/kernel/vm_events.c:83:6: warning: no previous prototype for function 'arch_do_IRQ' [-Wmissing-prototypes]
     83 | void arch_do_IRQ(struct pt_regs *regs)
        |      ^
  arch/hexagon/kernel/vm_events.c:83:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     83 | void arch_do_IRQ(struct pt_regs *regs)
        | ^
        | static

This function is only called from assembly but the irq header is a
reasonable place to put a prototype to silence the warning.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-17-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: vm_events: remove unused dummy_handler()

Clang warns:

  arch/hexagon/kernel/vm_events.c:76:6: warning: no previous prototype for function 'dummy_handler' [-Wmissing-prototypes]
     76 | void dummy_handler(struct pt_regs *regs)
        |      ^
  arch/hexagon/kernel/vm_events.c:76:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     76 | void dummy_handler(struct pt_regs *regs)
        | ^
        | static

This function appears to be entirely unused, so remove it.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-16-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: vdso: include asm/elf.h for arch_setup_additional_pages() prototype

Clang warns:

  arch/hexagon/kernel/vdso.c:49:5: warning: no previous prototype for function 'arch_setup_additional_pages' [-Wmissing-prototypes]
     49 | int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
        |     ^
  arch/hexagon/kernel/vdso.c:49:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     49 | int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
        | ^
        | static
  1 warning generated.

Include the header that declares the prototype to clear up the warning.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-15-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: process: add internal prototype for do_work_pending()

Clang warns:

  arch/hexagon/kernel/process.c:155:5: warning: no previous prototype for function 'do_work_pending' [-Wmissing-prototypes]
    155 | int do_work_pending(struct pt_regs *regs, u32 thread_info_flags)
        |     ^
  arch/hexagon/kernel/process.c:155:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    155 | int do_work_pending(struct pt_regs *regs, u32 thread_info_flags)
        | ^
        | static

This function is only referenced from assembly, so it does not technically
need a prototype.  Add one right above the definition anyways to clear up
the warning.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-14-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: process: include linux/cpu.h for arch_cpu_idle() prototype

Clang warns:

  arch/hexagon/kernel/process.c:43:6: warning: no previous prototype for function 'arch_cpu_idle' [-Wmissing-prototypes]
     43 | void arch_cpu_idle(void)
        |      ^
  arch/hexagon/kernel/process.c:43:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     43 | void arch_cpu_idle(void)
        | ^
        | static

This prototype is declared in include/linux/cpu.h, include it in
process.c to clear up the warning.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-13-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: reset: include linux/reboot.h for prototypes

Clang warns about missing prototypes that are declared in this header:

  arch/hexagon/kernel/reset.c:9:6: warning: no previous prototype for function 'machine_power_off' [-Wmissing-prototypes]
      9 | void machine_power_off(void)
        |      ^
  arch/hexagon/kernel/reset.c:9:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
      9 | void machine_power_off(void)
        | ^
        | static
  arch/hexagon/kernel/reset.c:15:6: warning: no previous prototype for function 'machine_halt' [-Wmissing-prototypes]
     15 | void machine_halt(void)
        |      ^
  arch/hexagon/kernel/reset.c:15:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     15 | void machine_halt(void)
        | ^
        | static
  arch/hexagon/kernel/reset.c:19:6: warning: no previous prototype for function 'machine_restart' [-Wmissing-prototypes]
     19 | void machine_restart(char *cmd)
        |      ^
  arch/hexagon/kernel/reset.c:19:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     19 | void machine_restart(char *cmd)
        | ^
        | static
  3 warnings generated.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-12-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: signal: switch to SYSCALL_DEFINE0 for sys_rt_sigreturn()

Clang warns:

  arch/hexagon/kernel/signal.c:223:16: warning: no previous prototype for function 'sys_rt_sigreturn' [-Wmissing-prototypes]
    223 | asmlinkage int sys_rt_sigreturn(void)
        |                ^
  arch/hexagon/kernel/signal.c:223:12: note: declare 'static' if the function is not intended to be used outside of this translation unit
    223 | asmlinkage int sys_rt_sigreturn(void)
        |            ^
        |            static
  1 warning generated.

Switch to the SYSCALL_DEFINE0() macro, which automatically declares a
prototype.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-11-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: time: include asm/delay.h for prototypes

Clang warns about missing prototypes that are declared in this header:

  arch/hexagon/kernel/time.c:209:6: warning: no previous prototype for function '__delay' [-Wmissing-prototypes]
    209 | void __delay(unsigned long cycles)
        |      ^
  arch/hexagon/kernel/time.c:209:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    209 | void __delay(unsigned long cycles)
        | ^
        | static
  arch/hexagon/kernel/time.c:224:6: warning: no previous prototype for function '__udelay' [-Wmissing-prototypes]
    224 | void __udelay(unsigned long usecs)
        |      ^
  arch/hexagon/kernel/time.c:224:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    224 | void __udelay(unsigned long usecs)
        | ^
        | static

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-10-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: time: mark time_init_deferred() as static

Clang warns:

  arch/hexagon/kernel/time.c:163:13: warning: no previous prototype for function 'time_init_deferred' [-Wmissing-prototypes]
    163 | void __init time_init_deferred(void)
        |             ^
  arch/hexagon/kernel/time.c:163:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    163 | void __init time_init_deferred(void)
        | ^
        | static

This function is not used outside of this translation unit so mark it as
static to resolve the warning.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-9-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: time: include asm/time.h for prototypes

Clang warns about missing prototypes that are declared in this header:

  arch/hexagon/kernel/time.c:118:6: warning: no previous prototype for function 'setup_percpu_clockdev' [-Wmissing-prototypes]
    118 | void setup_percpu_clockdev(void)
        |      ^
  arch/hexagon/kernel/time.c:118:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    118 | void setup_percpu_clockdev(void)
        | ^
        | static
  arch/hexagon/kernel/time.c:135:6: warning: no previous prototype for function 'ipi_timer' [-Wmissing-prototypes]
    135 | void ipi_timer(void)
        |      ^
  arch/hexagon/kernel/time.c:135:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    135 | void ipi_timer(void)
        | ^
        | static

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-8-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: vm_tlb: include asm/tlbflush.h for prototypes

Clang warns about several missing prototypes that are declared in this
header:

  arch/hexagon/mm/vm_tlb.c:25:6: warning: no previous prototype for function 'flush_tlb_range' [-Wmissing-prototypes]
     25 | void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
        |      ^
  arch/hexagon/mm/vm_tlb.c:25:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     25 | void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
        | ^
        | static
  arch/hexagon/mm/vm_tlb.c:37:6: warning: no previous prototype for function 'flush_tlb_one' [-Wmissing-prototypes]
     37 | void flush_tlb_one(unsigned long vaddr)
        |      ^
  arch/hexagon/mm/vm_tlb.c:37:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     37 | void flush_tlb_one(unsigned long vaddr)
        | ^
        | static
  arch/hexagon/mm/vm_tlb.c:47:6: warning: no previous prototype for function 'tlb_flush_all' [-Wmissing-prototypes]
     47 | void tlb_flush_all(void)
        |      ^
  arch/hexagon/mm/vm_tlb.c:47:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     47 | void tlb_flush_all(void)
        | ^
        | static
  arch/hexagon/mm/vm_tlb.c:56:6: warning: no previous prototype for function 'flush_tlb_mm' [-Wmissing-prototypes]
     56 | void flush_tlb_mm(struct mm_struct *mm)
        |      ^
  arch/hexagon/mm/vm_tlb.c:56:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     56 | void flush_tlb_mm(struct mm_struct *mm)
        | ^
        | static
  arch/hexagon/mm/vm_tlb.c:66:6: warning: no previous prototype for function 'flush_tlb_page' [-Wmissing-prototypes]
     66 | void flush_tlb_page(struct vm_area_struct *vma, unsigned long vaddr)
        |      ^
  arch/hexagon/mm/vm_tlb.c:66:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     66 | void flush_tlb_page(struct vm_area_struct *vma, unsigned long vaddr)
        | ^
        | static
  arch/hexagon/mm/vm_tlb.c:78:6: warning: no previous prototype for function 'flush_tlb_kernel_range' [-Wmissing-prototypes]
     78 | void flush_tlb_kernel_range(unsigned long start, unsigned long end)
        |      ^
  arch/hexagon/mm/vm_tlb.c:78:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     78 | void flush_tlb_kernel_range(unsigned long start, unsigned long end)
        | ^
        | static
  6 warnings generated.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-7-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: vm_fault: include asm/vm_fault.h for prototypes

Clang warns:

  arch/hexagon/mm/vm_fault.c:157:6: warning: no previous prototype for function 'read_protection_fault' [-Wmissing-prototypes]
    157 | void read_protection_fault(struct pt_regs *regs)
        |      ^
  arch/hexagon/mm/vm_fault.c:157:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    157 | void read_protection_fault(struct pt_regs *regs)
        | ^
        | static
  arch/hexagon/mm/vm_fault.c:164:6: warning: no previous prototype for function 'write_protection_fault' [-Wmissing-prototypes]
    164 | void write_protection_fault(struct pt_regs *regs)
        |      ^
  arch/hexagon/mm/vm_fault.c:164:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    164 | void write_protection_fault(struct pt_regs *regs)
        | ^
        | static
  arch/hexagon/mm/vm_fault.c:171:6: warning: no previous prototype for function 'execute_protection_fault' [-Wmissing-prototypes]
    171 | void execute_protection_fault(struct pt_regs *regs)
        |      ^
  arch/hexagon/mm/vm_fault.c:171:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    171 | void execute_protection_fault(struct pt_regs *regs)
        | ^
        | static

The prototypes for these functions are defined in asm/vm_fault.h, so
include it to pick them up and silence the warnings.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-6-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: vm_fault: mark do_page_fault() as static

Clang warns:

  arch/hexagon/mm/vm_fault.c:36:6: warning: no previous prototype for function 'do_page_fault' [-Wmissing-prototypes]
     36 | void do_page_fault(unsigned long address, long cause, struct pt_regs *regs)
        |      ^
  arch/hexagon/mm/vm_fault.c:36:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     36 | void do_page_fault(unsigned long address, long cause, struct pt_regs *regs)
        | ^
        | static

This function is not used outside of this translation unit, so mark it
as static.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-5-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: smp: mark handle_ipi() and start_secondary() as static

Clang warns:

  arch/hexagon/kernel/smp.c:82:13: warning: no previous prototype for function 'handle_ipi' [-Wmissing-prototypes]
     82 | irqreturn_t handle_ipi(int irq, void *desc)
        |             ^
  arch/hexagon/kernel/smp.c:82:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     82 | irqreturn_t handle_ipi(int irq, void *desc)
        | ^
        | static
  arch/hexagon/kernel/smp.c:127:6: warning: no previous prototype for function 'start_secondary' [-Wmissing-prototypes]
    127 | void start_secondary(void)
        |      ^
  arch/hexagon/kernel/smp.c:127:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    127 | void start_secondary(void)
        | ^
        | static
  2 warnings generated.

These functions are not used outside of this translation unit, so mark
them as static.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-4-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: mm: include asm/setup.h for setup_arch_memory()'s prototype

Clang warns:

  arch/hexagon/mm/init.c:138:13: warning: no previous prototype for function 'setup_arch_memory' [-Wmissing-prototypes]
    138 | void __init setup_arch_memory(void)
        |             ^
  arch/hexagon/mm/init.c:138:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    138 | void __init setup_arch_memory(void)
        | ^
        | static

The prototype is in asm/setup.h, include it to clear up the warning.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-3-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: mm: mark paging_init() as static

Clang warns:

  arch/hexagon/mm/init.c:89:13: warning: no previous prototype for function 'paging_init' [-Wmissing-prototypes]
     89 | void __init paging_init(void)
        |             ^
  arch/hexagon/mm/init.c:89:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     89 | void __init paging_init(void)
        | ^
        | static

This function is only used within this translation unit, so mark it static
as suggested.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-2-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

hexagon: uaccess: remove clear_user_hexagon()

Patch series "hexagon: Fix up instances of -Wmissing-prototypes".

This series fixes all the instances of -Wmissing-prototypes in
arch/hexagon, as it is about to be enabled globally in a default build.

This patch (of 19):

Clang warns:

  arch/hexagon/mm/uaccess.c:39:15: warning: no previous prototype for function 'clear_user_hexagon' [-Wmissing-prototypes]
     39 | unsigned long clear_user_hexagon(void __user *dest, unsigned long count)
        |               ^
  arch/hexagon/mm/uaccess.c:39:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
     39 | unsigned long clear_user_hexagon(void __user *dest, unsigned long count)
        | ^
        | static
  1 warning generated.

This function appears to have been unused since it was introduced in
commit 7567746e1c0d ("Hexagon: Add user access functions"), so remove it.

Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-0-5c34714afe9e@kernel.org
Link: https://lkml.kernel.org/r/20231130-hexagon-missing-prototypes-v1-1-5c34714afe9e@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch: turn off -Werror for architectures with known warnings

A couple of architectures enable -Werror for their own files regardless of
CONFIG_WERROR but also have known warnings that fail the build with
-Wmissing-prototypes enabled by default:

arch/alpha/lib/memcpy.c:153:8: error: no previous prototype for 'memcpy' [-Werror=missing-prototypes]
arch/alpha/kernel/irq.c:96:1: error: no previous prototype for 'handle_irq' [-Werror=missing-prototypes]
arch/mips/kernel/signal.c:673:17: error: no previous prototype for ‘sys_rt_sigreturn’ [-Werror=missing-prototypes]
arch/mips/kernel/signal.c:636:17: error: no previous prototype for ‘sys_sigreturn’ [-Werror=missing-prototypes]
arch/mips/kernel/syscall.c:51:16: error: no previous prototype for ‘sysm_pipe’ [-Werror=missing-prototypes]
arch/mips/mm/fault.c:323:17: error: no previous prototype for ‘do_page_fault’ [-Werror=missing-prototypes]
arch/sparc/vdso/vma.c:246:12: warning: no previous prototype for ‘init_vdso_image’ [-Wmissing-prototypes]v
arch/sparc/vdso/vdso32/../vclock_gettime.c:343:1: warning: no previous prototype for ‘__vdso_gettimeofday_stick’ [-Wmissing-prototypes]
arch/sparc/vdso/vclock_gettime.c:343:1: warning: no previous prototype for ‘__vdso_gettimeofday_stick’ [-Wmissing-prototypes]
arch/sparc/prom/p1275.c:52:6: warning: no previous prototype for ‘prom_cif_init’ [-Wmissing-prototypes]
arch/sparc/prom/misc_64.c:165:5: warning: no previous prototype for ‘prom_get_mmu_ihandle’ [-Wmissing-prototypes]

This appears to be an artifact from the times when this architecture code
was better maintained that most device drivers and before CONFIG_WERROR
was added.  Now it just gets in the way, so remove all of these.

Powerpc and x86 both still have their own Kconfig options to enable
-Werror for some of their files.  These architectures are better
maintained than most and the options are easy to disable, so leave those
untouched.

Link: https://lkml.kernel.org/r/4be73872-c1f5-4c31-8201-712c19290a22@app.fastmail.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: Stephen Rothwell <sfr@rothwell.id.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kexec: use atomic_try_cmpxchg in crash_kexec

Use atomic_try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in
crash_kexec().  x86 CMPXCHG instruction returns success in ZF flag,
so this change saves a compare after cmpxchg.

No functional change intended.

Link: https://lkml.kernel.org/r/20231114161228.108516-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

scripts/spelling.txt: add more spellings to spelling.txt

Some of the more common spelling mistakes and typos that I've found while
fixing up spelling mistakes in the kernel over the past couple of
releases.

Link: https://lkml.kernel.org/r/20231122104037.1770749-1-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>

__ptrace_unlink: kill the obsolete "FIXME" code

The corner case described by the comment is no longer possible after the
commit 7b3c36fc4c23 ("ptrace: fix task_join_group_stop() for the case when
current is traced"), task_join_group_stop() ensures that the new thread
has the correct signr in JOBCTL_STOP_SIGMASK regardless of ptrace.

Link: https://lkml.kernel.org/r/20231121162650.GA6635@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

checkstack: allow to pass MINSTACKSIZE parameter

The checkstack script omits all functions with a stack usage of less than
100 bytes.  However the script already has support for a parameter which
allows to override the default, but it cannot be set with

$ make checkstack

Add a MINSTACKSIZE parameter which allows to change the default. This might
be useful in order to print the stack usage of all functions, or only those
with large stack usage:

$ make checkstack MINSTACKSIZE=0
$ make checkstack MINSTACKSIZE=800

Link: https://lkml.kernel.org/r/20231120183719.2188479-4-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Cc: Maninder Singh <maninder1.s@samsung.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

checkstack: sort output by size and function name

Sort output by size and in addition by function name.  This increases
readability for cases where there are many functions with the same stack
usage.

Link: https://lkml.kernel.org/r/20231120183719.2188479-3-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Cc: Maninder Singh <maninder1.s@samsung.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kernel/signal.c: simplify force_sig_info_to_task(), kill recalc_sigpending_and_wake()

The purpose of recalc_sigpending_and_wake() is not clear, it looks
"obviously unneeded" because we are going to send the signal which can't
be blocked or ignored.

Add the comment to explain why we can't rely on send_signal_locked() and
make this logic more simple/explicit.  recalc_sigpending_and_wake() has no
other users, it can die.

In fact I think we don't even need signal_wake_up(), the target task must
be either current or a TASK_TRACED child, otherwise the usage of siglock
is not safe.  But this needs another change.

Link: https://lkml.kernel.org/r/20231120151649.GA15995@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

docs: filesystems: document the squashfs specific mount options

When SQUASHFS_CHOICE_DECOMP_BY_MOUNT is set, the "threads" mount option
can be used to specify the decompression mode: single-threaded,
multi-threaded, percpu or the number of threads used for decompression.
When SQUASHFS_CHOICE_DECOMP_BY_MOUNT is not set, SQUASHFS_DECOMP_MULTI and
SQUASHFS_MOUNT_DECOMP_THREADS are both set, the "threads" option can also
be used to specify the number of threads used for decompression.  This
mount option is only mentioned in fs/squashfs/Kconfig, which makes it
difficult to find.

Another mount option available is "errors", which can be configured to
panic the kernel when squashfs errors are encountered.

Add both these options to the squashfs documentation, making them more
noticeable.

Link: https://lkml.kernel.org/r/20231117161215.140282-1-amiculas@cisco.com
Signed-off-by: Ariel Miculas <amiculas@cisco.com>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Phillip Lougher <phillip@squashfs.org.uk>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

checkpatch: do not require an empty line before error injection

ALLOW_ERROR_INJECTION macro (just like EXPORT_SYMBOL) can immediately
follow a function it annotates.

Link: https://lkml.kernel.org/r/20231109075147.2779461-1-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com> (maintainer:CHECKPATCH)
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com> (reviewer:CHECKPATCH)
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch: remove ARCH_TASK_STRUCT_ON_STACK

IA-64 was the only architecture which selected ARCH_TASK_STRUCT_ON_STACK.
IA-64 was removed with commit cf8e8658100d ("arch: Remove Itanium (IA-64)
architecture"). Therefore remove support for ARCH_TASK_STRUCT_ON_STACK
as well.

Note: this also reveals a potential bug in powerpc code, which makes use of
__init_task_data without selecting ARCH_TASK_STRUCT_ON_STACK which makes
__init_task_data a no-op. This is broken since commit d11ed3ab3166 ("Expand
INIT_TASK() in init/init_task.c and remove") from 2018 and needs to be
addressed separately.

Link: https://lkml.kernel.org/r/20231116133638.1636277-4-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch: remove ARCH_TASK_STRUCT_ALLOCATOR

IA-64 was the only architecture which selected ARCH_TASK_STRUCT_ALLOCATOR.
IA-64 was removed with commit cf8e8658100d ("arch: Remove Itanium (IA-64)
architecture"). Therefore remove support for ARCH_THREAD_STACK_ALLOCATOR
as well.

Link: https://lkml.kernel.org/r/20231116133638.1636277-3-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch: remove ARCH_THREAD_STACK_ALLOCATOR

Patch series "Remove unused code after IA-64 removal".

While looking into something different I noticed that there are a couple
of Kconfig options which were only selected by IA-64 and which are now
unused.

So remove them and simplify the code a bit.

This patch (of 3):

IA-64 was the only architecture which selected ARCH_THREAD_STACK_ALLOCATOR.
IA-64 was removed with commit cf8e8658100d ("arch: Remove Itanium (IA-64)
architecture"). Therefore remove support for ARCH_THREAD_STACK_ALLOCATOR as
well.

Link: https://lkml.kernel.org/r/20231116133638.1636277-1-hca@linux.ibm.com
Link: https://lkml.kernel.org/r/20231116133638.1636277-2-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_btnode_abort_change_key to use a folio

Saves one call to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-21-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: convert nilfs_btnode_commit_change_key to use a folio

Saves one call to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-20-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>