From 1d6f1d16d3a36351a6718378790497f1ba3b5378 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Fri, 27 Sep 2019 17:03:35 +0100
Subject: drm/i915/gt: Only unwedge if we can reset first
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Git-commit: 1d6f1d16d3a36351a6718378790497f1ba3b5378
Patch-mainline: v5.5-rc1
References: bsc#1152489
Unwedging the GPU requires a successful GPU reset before we restore the
default submission, or else we may see residual context switch events
that we were not expecting.
v2: Pull in the special-case reset_clobbers_display, and explain why it
should be safe in the context of unwedging.
v3: Just forget all about resets before unwedging if it will clobber the
display; risk it all.
Reported-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> #v1
Link: https://patchwork.freedesktop.org/patch/msgid/20190927160335.10622-1-chris@chris-wilson.co.uk
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
---
drivers/gpu/drm/i915/gt/intel_reset.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_reset.c b/drivers/gpu/drm/i915/gt/intel_reset.c
index 76938fa3a1b9..e189897e8797 100644
--- a/drivers/gpu/drm/i915/gt/intel_reset.c
+++ b/drivers/gpu/drm/i915/gt/intel_reset.c
@@ -821,6 +821,7 @@ static bool __intel_gt_unset_wedged(struct intel_gt *gt)
struct intel_gt_timelines *timelines = >->timelines;
struct intel_timeline *tl;
unsigned long flags;
+ bool ok;
if (!test_bit(I915_WEDGED, >->reset.flags))
return true;
@@ -867,7 +868,12 @@ static bool __intel_gt_unset_wedged(struct intel_gt *gt)
}
spin_unlock_irqrestore(&timelines->lock, flags);
- intel_gt_sanitize(gt, false);
+ /* We must reset pending GPU events before restoring our submission */
+ ok = !HAS_EXECLISTS(gt->i915); /* XXX better agnosticism desired */
+ if (!INTEL_INFO(gt->i915)->gpu_reset_clobbers_display)
+ ok = __intel_gt_reset(gt, ALL_ENGINES) == 0;
+ if (!ok)
+ return false;
/*
* Undo nop_submit_request. We prevent all new i915 requests from
--
2.28.0