| Message ID | 20170717091141.23102-3-chris@chris-wilson.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 17/07/17 02:11, Chris Wilson wrote: > We rely on disabling the execlists (by stopping the tasklet) to prevent > new requests from submitting to the engine ELSP before we are ready. > However, we re-enable the engine before we call init_hw which gives > userspace the opportunity to subit a new request which is then > overwritten by init_hw -- but not before the HW may have started > executing. The subsequent out-of-order CSB is detected by our sanity > checks in intel_lrc_irq_handler(). > > Fixes: a1ef70e14453 ("drm/i915: Add support for per engine reset recovery") > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> > Cc: Michel Thierry <michel.thierry@intel.com> > Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> > --- > drivers/gpu/drm/i915/i915_drv.c | 16 +++++++--------- > 1 file changed, 7 insertions(+), 9 deletions(-) > > diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c > index 901c3ff61527..bc121a46ed9a 100644 > --- a/drivers/gpu/drm/i915/i915_drv.c > +++ b/drivers/gpu/drm/i915/i915_drv.c > @@ -1955,6 +1955,12 @@ int i915_reset_engine(struct intel_engine_cs *engine) > } > > ret = intel_gpu_reset(engine->i915, intel_engine_flag(engine)); > + if (ret) { > + /* If we fail here, we expect to fallback to a global reset */ > + DRM_DEBUG_DRIVER("Failed to reset %s, ret=%d\n", > + engine->name, ret); > + goto out; > + } > > /* > * The request that caused the hang is stuck on elsp, we know the > @@ -1963,15 +1969,6 @@ int i915_reset_engine(struct intel_engine_cs *engine) > */ > i915_gem_reset_engine(engine, active_request); > > - i915_gem_reset_finish_engine(engine); > - > - if (ret) { > - /* If we fail here, we expect to fallback to a global reset */ > - DRM_DEBUG_DRIVER("Failed to reset %s, ret=%d\n", > - engine->name, ret); > - goto out; > - } > - > /* > * The engine and its registers (and workarounds in case of render) > * have been reset to their default values. Follow the init_ring > @@ -1983,6 +1980,7 @@ int i915_reset_engine(struct intel_engine_cs *engine) > > error->reset_engine_count[engine->id]++; > out: > + i915_gem_reset_finish_engine(engine); > return ret; > } > > Reviewed-by: Michel Thierry <michel.thierry@intel.com>
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 901c3ff61527..bc121a46ed9a 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -1955,6 +1955,12 @@ int i915_reset_engine(struct intel_engine_cs *engine) } ret = intel_gpu_reset(engine->i915, intel_engine_flag(engine)); + if (ret) { + /* If we fail here, we expect to fallback to a global reset */ + DRM_DEBUG_DRIVER("Failed to reset %s, ret=%d\n", + engine->name, ret); + goto out; + } /* * The request that caused the hang is stuck on elsp, we know the @@ -1963,15 +1969,6 @@ int i915_reset_engine(struct intel_engine_cs *engine) */ i915_gem_reset_engine(engine, active_request); - i915_gem_reset_finish_engine(engine); - - if (ret) { - /* If we fail here, we expect to fallback to a global reset */ - DRM_DEBUG_DRIVER("Failed to reset %s, ret=%d\n", - engine->name, ret); - goto out; - } - /* * The engine and its registers (and workarounds in case of render) * have been reset to their default values. Follow the init_ring @@ -1983,6 +1980,7 @@ int i915_reset_engine(struct intel_engine_cs *engine) error->reset_engine_count[engine->id]++; out: + i915_gem_reset_finish_engine(engine); return ret; }
We rely on disabling the execlists (by stopping the tasklet) to prevent new requests from submitting to the engine ELSP before we are ready. However, we re-enable the engine before we call init_hw which gives userspace the opportunity to subit a new request which is then overwritten by init_hw -- but not before the HW may have started executing. The subsequent out-of-order CSB is detected by our sanity checks in intel_lrc_irq_handler(). Fixes: a1ef70e14453 ("drm/i915: Add support for per engine reset recovery") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Michel Thierry <michel.thierry@intel.com> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> --- drivers/gpu/drm/i915/i915_drv.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-)