On Sat, Sep 01, 2018 at 01:32:54PM +0100, Chris Wilson wrote: > Quoting Jia-Ju Bai (2018-09-01 13:20:41) > > The driver may sleep with holding a spinlock. > > > > The function call paths (from bottom to top) in Linux-4.16 are: > > > > [FUNC] kmalloc(GFP_KERNEL) > > drivers/gpu/drm/drm_mm.c, 130: > > kmalloc in show_leaks > > drivers/gpu/drm/drm_mm.c, 913: > > show_leaks in drm_mm_takedown > > drivers/gpu/drm/drm_vma_manager.c, 107: > > drm_mm_takedown in drm_vma_offset_manager_destroy > > drivers/gpu/drm/drm_vma_manager.c, 106: > > _raw_write_lock in drm_vma_offset_manager_destroy > > > > [FUNC] kmalloc(GFP_KERNEL) > > drivers/gpu/drm/drm_mm.c, 130: > > kmalloc in show_leaks > > drivers/gpu/drm/drm_mm.c, 913: > > show_leaks in drm_mm_takedown > > drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c, 71: > > drm_mm_takedown in amdgpu_vram_mgr_fini > > drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c, 70: > > spin_lock in amdgpu_vram_mgr_fini > > > > [FUNC] kmalloc(GFP_KERNEL) > > drivers/gpu/drm/drm_mm.c, 130: > > kmalloc in show_leaks > > drivers/gpu/drm/drm_mm.c, 913: > > show_leaks in drm_mm_takedown > > drivers/gpu/drm/ttm/ttm_bo_manager.c, 128: > > drm_mm_takedown in ttm_bo_man_takedown > > drivers/gpu/drm/ttm/ttm_bo_manager.c, 126: > > spin_lock in ttm_bo_man_takedown > > > > To fix this bug, GFP_KERNEL is replaced with GFP_ATOMIC. > > The bug are above, since those spinlocks do not protect the data and > imply use-after-free. Adding amdgpu, since that's where the bug seems to be. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch
