drm/amdgpu: fix issue with overlapping userptrs
authorChristian König <christian.koenig@amd.com>
Mon, 8 Feb 2016 09:57:22 +0000 (10:57 +0100)
committerAlex Deucher <alexander.deucher@amd.com>
Wed, 10 Feb 2016 19:07:52 +0000 (14:07 -0500)
Otherwise we could try to evict overlapping userptr BOs in get_user_pages(),
leading to a possible circular locking dependency.

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
drivers/gpu/drm/amd/amdgpu/amdgpu.h
drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c

index 43e7ed1e74e72998c52de2477cb9f19230d759a0..5e7770f9a415be24140df77708e9d9d39dee7faa 100644 (file)
@@ -2319,6 +2319,8 @@ bool amdgpu_ttm_bo_is_amdgpu_bo(struct ttm_buffer_object *bo);
 int amdgpu_ttm_tt_set_userptr(struct ttm_tt *ttm, uint64_t addr,
                                     uint32_t flags);
 bool amdgpu_ttm_tt_has_userptr(struct ttm_tt *ttm);
+bool amdgpu_ttm_tt_affect_userptr(struct ttm_tt *ttm, unsigned long start,
+                                 unsigned long end);
 bool amdgpu_ttm_tt_is_readonly(struct ttm_tt *ttm);
 uint32_t amdgpu_ttm_tt_pte_flags(struct amdgpu_device *adev, struct ttm_tt *ttm,
                                 struct ttm_mem_reg *mem);
index b1969f2b2038db79af8447fc9826ba8257207cf4..d4e2780c079663a643bddeaa7e2da5e15a2ff47d 100644 (file)
@@ -142,7 +142,8 @@ static void amdgpu_mn_invalidate_range_start(struct mmu_notifier *mn,
 
                list_for_each_entry(bo, &node->bos, mn_list) {
 
-                       if (!bo->tbo.ttm || bo->tbo.ttm->state != tt_bound)
+                       if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm, start,
+                                                         end))
                                continue;
 
                        r = amdgpu_bo_reserve(bo, true);
index 55cf05e1c81c398fc747f598d1ce0bc78a38a435..6442a06d6fdc1ce9115d280cc916b4e55923f2fa 100644 (file)
@@ -783,6 +783,25 @@ bool amdgpu_ttm_tt_has_userptr(struct ttm_tt *ttm)
        return !!gtt->userptr;
 }
 
+bool amdgpu_ttm_tt_affect_userptr(struct ttm_tt *ttm, unsigned long start,
+                                 unsigned long end)
+{
+       struct amdgpu_ttm_tt *gtt = (void *)ttm;
+       unsigned long size;
+
+       if (gtt == NULL)
+               return false;
+
+       if (gtt->ttm.ttm.state != tt_bound || !gtt->userptr)
+               return false;
+
+       size = (unsigned long)gtt->ttm.ttm.num_pages * PAGE_SIZE;
+       if (gtt->userptr > end || gtt->userptr + size <= start)
+               return false;
+
+       return true;
+}
+
 bool amdgpu_ttm_tt_is_readonly(struct ttm_tt *ttm)
 {
        struct amdgpu_ttm_tt *gtt = (void *)ttm;