From ddab49e2d63d5dadc60449724fd7fd6cc9af6002 Mon Sep 17 00:00:00 2001 From: "Le.Ma" Date: Fri, 22 Sep 2017 10:56:57 +0800 Subject: [PATCH 0958/4131] drm/amdgpu: [KFD] Fix rw_semaphore usage Avoid accessing current pointer in amdgpu_ttm_tt_get_user_pages(), which will cause NULL pointer oops. And remove uneeded rw_semaphore. This fix accords with kfd branch. Change-Id: I0a602b30a20eb444968d6e846f3adca6cfff841a Signed-off-by: Le.Ma Reviewed-by: Junwei Zhang --- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index dd9e59a..fc82765 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -680,7 +680,7 @@ int amdgpu_ttm_tt_get_user_pages(struct ttm_tt *ttm, struct page **pages) if (!(gtt->userflags & AMDGPU_GEM_USERPTR_READONLY)) flags |= FOLL_WRITE; - down_read(¤t->mm->mmap_sem); + down_read(&mm->mmap_sem); if (gtt->userflags & AMDGPU_GEM_USERPTR_ANONONLY) { /* check that we only use anonymous memory @@ -690,7 +690,7 @@ int amdgpu_ttm_tt_get_user_pages(struct ttm_tt *ttm, struct page **pages) vma = find_vma(mm, gtt->userptr); if (!vma || vma->vm_file || vma->vm_end < end) { - up_read(¤t->mm->mmap_sem); + up_read(&mm->mmap_sem); return -EPERM; } } @@ -719,12 +719,12 @@ int amdgpu_ttm_tt_get_user_pages(struct ttm_tt *ttm, struct page **pages) } while (pinned < ttm->num_pages); - up_read(¤t->mm->mmap_sem); + up_read(&mm->mmap_sem); return 0; release_pages: release_pages(pages, pinned, 0); - up_read(¤t->mm->mmap_sem); + up_read(&mm->mmap_sem); return r; } -- 2.7.4