I've tested your change and one issue gone. However I still see kernel crash (due to invalid read in kernel mode by 0x0 address) on weston stop: ----------------------------------->8------------------------------------------- Oops Path: (null) CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.7.0-rc6-01594-g4ceda91a4176-dirty #6 Workqueue: events drm_mode_rmfb_work_fn Invalid Read @ 0x00000000 by insn @ drm_gem_fb_destroy+0x32/0x130 ECR: 0x00050100 EFA: 0x00000000 ERET: 0x813b9a76 STAT32: 0x80080602 [IE K ] BTA: 0x813b9a72 BLK: drm_gem_fb_destroy+0xc0/0x130 SP: 0x9f055ea4 FP: 0x00000000 LPS: 0x813560ec LPE: 0x813560f0 LPC: 0x00000000 r00: 0x00000000 r01: 0x9f6a6100 r02: 0x00000001 r03: 0x9fd5dde8 r04: 0x810f5de8 r05: 0x00000000 r06: 0x00000000 r07: 0x00000000 r08: 0x000000e1 r09: 0x00000000 r10: 0x00000000 r11: 0x000000e1 r12: 0x813b9b04 Stack Trace: drm_gem_fb_destroy+0x32/0x130 drm_framebuffer_remove+0x1d2/0x358 drm_mode_rmfb_work_fn+0x28/0x38 process_one_work+0x19a/0x358 worker_thread+0x2c4/0x494 kthread+0xec/0x100 ret_from_fork+0x18/0x1c ----------------------------------->8------------------------------------------- The stack traces may vary but always end in drm_gem_fb_destroy: ----------------------------------->8------------------------------------------- Stack Trace: drm_gem_fb_destroy+0x32/0x130 drm_mode_rmfb+0x10e/0x148 drm_ioctl_kernel+0x70/0xa0 drm_ioctl+0x284/0x410 ksys_ioctl+0xea/0xa3c EV_Trap+0xcc/0xd0 ----------------------------------->8------------------------------------------- Stack Trace: drm_gem_fb_destroy+0x32/0x130 drm_fb_release+0x66/0xb0 drm_file_free.part.11+0x112/0x1bc drm_release+0x80/0x120 __fput+0x98/0x1bc task_work_run+0x6e/0xa8 do_exit+0x2b4/0x7fc do_group_exit+0x2a/0x8c get_signal+0x9a/0x5f0 do_signal+0x86/0x23c resume_user_mode_begin+0x88/0xd0 ----------------------------------->8------------------------------------------- --- Eugeniy Paltsev ________________________________________ From: Daniel Vetter <daniel@xxxxxxxx> Sent: Thursday, June 4, 2020 14:19 To: Eugeniy Paltsev Cc: Intel Graphics Development; DRI Development; Daniel Vetter; Sam Ravnborg; Alexey Brodkin Subject: Re: [PATCH 53/59] drm/arc: Move to drm/tiny Hi Eugeniy, Apologies, somehow I missed your mail. I looked at the code again, and I think I fumbled something. Does the below diff help to prevent the issues? Thanks, Daniel diff --git a/drivers/gpu/drm/tiny/arcpgu.c b/drivers/gpu/drm/tiny/arcpgu.c index 857812f25bec..33d812a5ad7f 100644 --- a/drivers/gpu/drm/tiny/arcpgu.c +++ b/drivers/gpu/drm/tiny/arcpgu.c @@ -228,6 +228,9 @@ static void arc_pgu_update(struct drm_simple_display_pipe *pipe, struct arcpgu_drm_private *arcpgu; struct drm_gem_cma_object *gem; + if (!pipe->plane.state->fb) + return; + arcpgu = pipe_to_arcpgu_priv(pipe); gem = drm_fb_cma_get_gem_obj(pipe->plane.state->fb, 0); arc_pgu_write(arcpgu, ARCPGU_REG_BUF0_ADDR, gem->paddr); -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - https://urldefense.com/v3/__http://blog.ffwll.ch__;!!A4F2R9G_pg!P0EvyJfMuDwqbeZmHZM5S9po30QWr4KgGrggRirNfgo7wrRXfnUO-8iq0AA4fQCW2WGPlDc$ _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel