From b87482dfe800f326f8f5b0093273ee6bd5b5fe9f Mon Sep 17 00:00:00 2001 From: Matthew Auld Date: Thu, 27 May 2021 19:51:45 +0100 Subject: [PATCH] Revert "i915: use io_mapping_map_user" This reverts commit b739f125e4ebd73d10ed30a856574e13649119ed. We are unfortunately seeing more issues like we did in 293837b9ac8d ("Revert "i915: fix remap_io_sg to verify the pgprot""), except this is now for the vm_fault_gtt path, where we are now hitting the same BUG_ON(!pte_none(*pte)): [10887.466150] kernel BUG at mm/memory.c:2183! [10887.466162] invalid opcode: 0000 [#1] PREEMPT SMP PTI [10887.466168] CPU: 0 PID: 7775 Comm: ffmpeg Tainted: G U 5.13.0-rc3-CI-Nightly #1 [10887.466174] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./J4205-ITX, BIOS P1.40 07/14/2017 [10887.466177] RIP: 0010:remap_pfn_range_notrack+0x30f/0x440 [10887.466188] Code: e8 96 d7 e0 ff 84 c0 0f 84 27 01 00 00 48 ba 00 f0 ff ff ff ff 0f 00 4c 89 e0 48 c1 e0 0c 4d 85 ed 75 96 48 21 d0 31 f6 eb a9 <0f> 0b 48 39 37 0f 85 0e 01 00 00 48 8b 0c 24 48 39 4f 08 0f 85 00 [10887.466193] RSP: 0018:ffffc90006e33c50 EFLAGS: 00010286 [10887.466198] RAX: 800000000000002f RBX: 00007f5e01800000 RCX: 0000000000000028 [10887.466201] RDX: 0000000000000001 RSI: ffffea0000000000 RDI: 0000000000000000 [10887.466204] RBP: ffffea000033fea8 R08: 800000000000002f R09: ffff8881072256e0 [10887.466207] R10: ffffc9000b84fff8 R11: 0000000017dab000 R12: 0000000000089f9f [10887.466210] R13: 800000000000002f R14: 00007f5e017e4000 R15: ffff88800cffaf20 [10887.466213] FS: 00007f5e04849640(0000) GS:ffff888278000000(0000) knlGS:0000000000000000 [10887.466216] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [10887.466220] CR2: 00007fd9b191a2ac CR3: 00000001829ac000 CR4: 00000000003506f0 [10887.466223] Call Trace: [10887.466233] vm_fault_gtt+0x1ca/0x5d0 [i915] [10887.466381] ? ktime_get+0x38/0x90 [10887.466389] __do_fault+0x37/0x90 [10887.466395] __handle_mm_fault+0xc46/0x1200 [10887.466402] handle_mm_fault+0xce/0x2a0 [10887.466407] do_user_addr_fault+0x1c5/0x660 Reverting this commit is reported to fix the issue. Reported-by: Eero Tamminen References: https://gitlab.freedesktop.org/drm/intel/-/issues/3519 Fixes: b739f125e4eb ("i915: use io_mapping_map_user") Cc: Christoph Hellwig Cc: Daniel Vetter Signed-off-by: Matthew Auld Acked-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20210527185145.458021-1-matthew.auld@intel.com (cherry picked from commit 0e4fe0c9f2f981f26e01b73f3c465ca314c4f9c0) Signed-off-by: Jani Nikula --- drivers/gpu/drm/i915/Kconfig | 1 - drivers/gpu/drm/i915/gem/i915_gem_mman.c | 9 ++--- drivers/gpu/drm/i915/i915_drv.h | 3 ++ drivers/gpu/drm/i915/i915_mm.c | 44 ++++++++++++++++++++++++ 4 files changed, 52 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig index 93f4d059fc89..1e1cb245fca7 100644 --- a/drivers/gpu/drm/i915/Kconfig +++ b/drivers/gpu/drm/i915/Kconfig @@ -20,7 +20,6 @@ config DRM_I915 select INPUT if ACPI select ACPI_VIDEO if ACPI select ACPI_BUTTON if ACPI - select IO_MAPPING select SYNC_FILE select IOSF_MBI select CRC32 diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c index f6fe5cb01438..8598a1c78a4c 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c @@ -367,10 +367,11 @@ retry: goto err_unpin; /* Finally, remap it using the new GTT offset */ - ret = io_mapping_map_user(&ggtt->iomap, area, area->vm_start + - (vma->ggtt_view.partial.offset << PAGE_SHIFT), - (ggtt->gmadr.start + vma->node.start) >> PAGE_SHIFT, - min_t(u64, vma->size, area->vm_end - area->vm_start)); + ret = remap_io_mapping(area, + area->vm_start + (vma->ggtt_view.partial.offset << PAGE_SHIFT), + (ggtt->gmadr.start + vma->node.start) >> PAGE_SHIFT, + min_t(u64, vma->size, area->vm_end - area->vm_start), + &ggtt->iomap); if (ret) goto err_fence; diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 9ec9277539ec..69e43bf91a15 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1905,6 +1905,9 @@ int i915_reg_read_ioctl(struct drm_device *dev, void *data, struct drm_file *file); /* i915_mm.c */ +int remap_io_mapping(struct vm_area_struct *vma, + unsigned long addr, unsigned long pfn, unsigned long size, + struct io_mapping *iomap); int remap_io_sg(struct vm_area_struct *vma, unsigned long addr, unsigned long size, struct scatterlist *sgl, resource_size_t iobase); diff --git a/drivers/gpu/drm/i915/i915_mm.c b/drivers/gpu/drm/i915/i915_mm.c index 9a777b0ff59b..666808cb3a32 100644 --- a/drivers/gpu/drm/i915/i915_mm.c +++ b/drivers/gpu/drm/i915/i915_mm.c @@ -37,6 +37,17 @@ struct remap_pfn { resource_size_t iobase; }; +static int remap_pfn(pte_t *pte, unsigned long addr, void *data) +{ + struct remap_pfn *r = data; + + /* Special PTE are not associated with any struct page */ + set_pte_at(r->mm, addr, pte, pte_mkspecial(pfn_pte(r->pfn, r->prot))); + r->pfn++; + + return 0; +} + #define use_dma(io) ((io) != -1) static inline unsigned long sgt_pfn(const struct remap_pfn *r) @@ -66,7 +77,40 @@ static int remap_sg(pte_t *pte, unsigned long addr, void *data) return 0; } +/** + * remap_io_mapping - remap an IO mapping to userspace + * @vma: user vma to map to + * @addr: target user address to start at + * @pfn: physical address of kernel memory + * @size: size of map area + * @iomap: the source io_mapping + * + * Note: this is only safe if the mm semaphore is held when called. + */ +int remap_io_mapping(struct vm_area_struct *vma, + unsigned long addr, unsigned long pfn, unsigned long size, + struct io_mapping *iomap) +{ + struct remap_pfn r; + int err; + #define EXPECTED_FLAGS (VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP) + GEM_BUG_ON((vma->vm_flags & EXPECTED_FLAGS) != EXPECTED_FLAGS); + + /* We rely on prevalidation of the io-mapping to skip track_pfn(). */ + r.mm = vma->vm_mm; + r.pfn = pfn; + r.prot = __pgprot((pgprot_val(iomap->prot) & _PAGE_CACHE_MASK) | + (pgprot_val(vma->vm_page_prot) & ~_PAGE_CACHE_MASK)); + + err = apply_to_page_range(r.mm, addr, size, remap_pfn, &r); + if (unlikely(err)) { + zap_vma_ptes(vma, addr, (r.pfn - pfn) << PAGE_SHIFT); + return err; + } + + return 0; +} /** * remap_io_sg - remap an IO mapping to userspace -- 2.20.1