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From: Matthew Auld <matthew.auld@intel.com> stable inclusion from stable-5.10.80 commit cbbf816cb7f9a84696b1f6277fee85c67a1c590c bugzilla: 185821 https://gitee.com/openeuler/kernel/issues/I4L7CG Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit f5d28856b89baab4232a9f841e565763fcebcdf9 ] In commit: commit 09ac4fcb3f255e9225967c75f5893325c116cdbe Author: Felix Kuehling <Felix.Kuehling@amd.com> Date: Thu Jul 13 17:01:16 2017 -0400 drm/ttm: Implement vm_operations_struct.access v2 we added the vm_access hook, where we also directly call tt_swapin for some reason. If something is swapped-out then the ttm_tt must also be unpopulated, and since access_kmap should also call tt_populate, if needed, then swapping-in will already be handled there. If anything, calling tt_swapin directly here would likely always fail since the tt->pages won't yet be populated, or worse since the tt->pages array is never actually cleared in unpopulate this might lead to a nasty uaf. Fixes: 09ac4fcb3f25 ("drm/ttm: Implement vm_operations_struct.access v2") Signed-off-by: Matthew Auld <matthew.auld@intel.com> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> Cc: Christian König <christian.koenig@amd.com> Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Christian König <christian.koenig@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20210927114114.152310-1-matthe... Signed-off-by: Christian König <christian.koenig@amd.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Reviewed-by: Weilong Chen <chenweilong@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- drivers/gpu/drm/ttm/ttm_bo_vm.c | 5 ----- 1 file changed, 5 deletions(-) diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c index 98a006fc30a5..0b1daf442425 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c @@ -500,11 +500,6 @@ int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr, switch (bo->mem.mem_type) { case TTM_PL_SYSTEM: - if (unlikely(bo->ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { - ret = ttm_tt_swapin(bo->ttm); - if (unlikely(ret != 0)) - return ret; - } fallthrough; case TTM_PL_TT: ret = ttm_bo_vm_access_kmap(bo, offset, buf, len, write); -- 2.20.1