On 2021-06-16 12:46 p.m., Michel Dänzer wrote: > From: Michel Dänzer <mdaenzer@xxxxxxxxxx> > > Once drm_framebuffer_init has returned 0, the framebuffer is hooked up > to the reference counting machinery and can no longer be destroyed with > a simple kfree. Therefore, it must be called last. > > Fixes: f258907fdd835e "drm/amdgpu: Verify bo size can fit framebuffer size on init." In case the commit log wasn't clear: If drm_framebuffer_init returns 0 but its caller then returns non-0, there will likely be memory corruption fireworks down the road. The following lead me to this fix: [ 12.891228] kernel BUG at lib/list_debug.c:25! [...] [ 12.891263] RIP: 0010:__list_add_valid+0x4b/0x70 [...] [ 12.891324] Call Trace: [ 12.891330] drm_framebuffer_init+0xb5/0x100 [drm] [ 12.891378] amdgpu_display_gem_fb_verify_and_init+0x47/0x120 [amdgpu] [ 12.891592] ? amdgpu_display_user_framebuffer_create+0x10d/0x1f0 [amdgpu] [ 12.891794] amdgpu_display_user_framebuffer_create+0x126/0x1f0 [amdgpu] [ 12.891995] drm_internal_framebuffer_create+0x378/0x3f0 [drm] [ 12.892036] ? drm_internal_framebuffer_create+0x3f0/0x3f0 [drm] [ 12.892075] drm_mode_addfb2+0x34/0xd0 [drm] [ 12.892115] ? drm_internal_framebuffer_create+0x3f0/0x3f0 [drm] [ 12.892153] drm_ioctl_kernel+0xe2/0x150 [drm] [ 12.892193] drm_ioctl+0x3da/0x460 [drm] [ 12.892232] ? drm_internal_framebuffer_create+0x3f0/0x3f0 [drm] [ 12.892274] amdgpu_drm_ioctl+0x43/0x80 [amdgpu] [ 12.892475] __se_sys_ioctl+0x72/0xc0 [ 12.892483] do_syscall_64+0x33/0x40 [ 12.892491] entry_SYSCALL_64_after_hwframe+0x44/0xae -- Earthling Michel Dänzer | https://redhat.com Libre software enthusiast | Mesa and X developer _______________________________________________ amd-gfx mailing list amd-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/amd-gfx
