From 4fc788f5ee3dba89c3269dcfafcc36136a1ffd0e Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 19 Aug 2016 16:54:23 +0100 Subject: [PATCH] drm/i915: Flush delayed fence releases after reset What I never hit in testing, but Mika immediately did, was a GPU hang with a pending fence release (where a tiled object has been changed by the user to be untiled, and the update has not yet been committed to the fence register). As the stride/tiling is 0, this causes a divide-by-zero error when trying to write the new fence parameters: [ 28.784518] drm/i915: Resetting chip after gpu hang [ 28.784551] divide error: 0000 [#1] PREEMPT SMP [ 28.784565] Modules linked in: nls_iso8859_1 nls_cp437 vfat fat mxm_wmi x86_pkg_temp_thermal snd_hda_codec_hdmi kvm irqbypass snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec serio_raw snd_hwdep snd_hda_core snd_pcm snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_timer snd_seq_device snd soundcore mac_hid wmi efivarfs autofs4 raid10 raid456 libcrc32c async_raid6_recov async_memcpy async_pq raid6_pq async_xor xor async_tx raid0 multipath linear psmouse e1000e ptp pps_core nvme nvme_core i915 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm video [ 28.784738] CPU: 0 PID: 1692 Comm: kworker/0:2 Not tainted 4.8.0-rc2+ #895 [ 28.784752] Hardware name: System manufacturer System Product Name/Z170M-PLUS, BIOS 1803 05/09/2016 [ 28.784786] Workqueue: events_long i915_hangcheck_elapsed [i915] [ 28.784814] task: ffff923c18f59d40 task.stack: ffff923c1b7e4000 [ 28.784827] RIP: 0010:[] [] fence_write+0x9f/0x3b0 [i915] [ 28.784854] RSP: 0018:ffff923c1b7e7b30 EFLAGS: 00010246 [ 28.784866] RAX: 00000000008ca000 RBX: ffff923c18540000 RCX: 0000000000000020 [ 28.784880] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000596d000 [ 28.784894] RBP: ffff923c1b7e7b68 R08: 0000000000000000 R09: 0000000000000000 [ 28.784908] R10: 0000000000000000 R11: 00000000008ca000 R12: ffff923c1ef9d600 [ 28.784921] R13: 0000000000100040 R14: 0000000000100044 R15: ffff923c18549908 [ 28.784935] FS: 0000000000000000(0000) GS:ffff923c36c00000(0000) knlGS:0000000000000000 [ 28.784951] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 28.784962] CR2: 00007f193373c893 CR3: 0000000419c78000 CR4: 00000000003406f0 [ 28.784976] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 28.784990] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 28.785004] Stack: [ 28.785009] 000000000596c03b ffff923c1b7e7b68 ffff923c18549938 0000000000000009 [ 28.785026] ffff923c18540000 ffff923c18549280 ffff923c18547ce8 ffff923c1b7e7b90 [ 28.785044] ffffffffc04761f9 ffff923c18540000 ffff923c18547d00 ffff923c18548ff8 [ 28.785062] Call Trace: [ 28.785078] [] i915_gem_restore_fences+0x39/0x50 [i915] [ 28.785102] [] i915_gem_reset+0x179/0x300 [i915] Reported-by: Mika Kuoppala Fixes: 49ef5294cda2 ("drm/i915: Move fence tracking from object to vma") Signed-off-by: Chris Wilson Cc: Mika Kuoppala Cc: Joonas Lahtinen Reviewed-by: Mika Kuoppala Link: http://patchwork.freedesktop.org/patch/msgid/20160819155428.1670-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_gem_fence.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gem_fence.c b/drivers/gpu/drm/i915/i915_gem_fence.c index dfe0a1a5e584..8df1fa7234e8 100644 --- a/drivers/gpu/drm/i915/i915_gem_fence.c +++ b/drivers/gpu/drm/i915/i915_gem_fence.c @@ -373,12 +373,16 @@ void i915_gem_restore_fences(struct drm_device *dev) for (i = 0; i < dev_priv->num_fence_regs; i++) { struct drm_i915_fence_reg *reg = &dev_priv->fence_regs[i]; + struct i915_vma *vma = reg->vma; /* * Commit delayed tiling changes if we have an object still * attached to the fence, otherwise just clear the fence. */ - fence_write(reg, reg->vma); + if (vma && !i915_gem_object_is_tiled(vma->obj)) + vma = NULL; + + fence_update(reg, vma); } } -- GitLab