We're seeing a GPU HANG issue on a CHV platform, which was caused by bac24f59f454 ("drm/i915/execlists: Enable coarse preemption boundaries for gen8").
Gen8 platform has only timeslice and doesn't support a preemption mechanism as engines do not have a preemption timer and doesn't send an irq if the preemption timeout expires. So, add a fix to not consider preemption during dequeuing for gen8 platforms.
v2: Simplify can_preempt() function (Tvrtko Ursulin)
v3: - Inside need_preempt(), condition of can_preempt() is not required as simplified can_preempt() is enough. (Chris Wilson)
Fixes: bac24f59f454 ("drm/i915/execlists: Enable coarse preemption boundaries for gen8") Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/11396 Suggested-by: Andi Shyti andi.shyti@intel.com Signed-off-by: Nitin Gote nitin.r.gote@intel.com Cc: Chris Wilson chris.p.wilson@linux.intel.com CC: stable@vger.kernel.org # v5.2+ --- drivers/gpu/drm/i915/gt/intel_execlists_submission.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c index 21829439e686..72090f52fb85 100644 --- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c +++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c @@ -3315,11 +3315,7 @@ static void remove_from_engine(struct i915_request *rq)
static bool can_preempt(struct intel_engine_cs *engine) { - if (GRAPHICS_VER(engine->i915) > 8) - return true; - - /* GPGPU on bdw requires extra w/a; not implemented */ - return engine->class != RENDER_CLASS; + return GRAPHICS_VER(engine->i915) > 8; }
static void kick_execlists(const struct i915_request *rq, int prio)