Quoting Tvrtko Ursulin (2017-12-19 12:26:38) > > On 19/12/2017 09:01, Chris Wilson wrote: > > After a reset, the state of the CSB registers are scrubbed and not valid > > until a powercontext is reloaded. We only know when a powercontext has > > been reloaded once we see a CS-interrupt, before then we must ignore the > > CSB registers within the execlists_submission_tasklet. However, glk is > > sporadically dying with an illegal CSB pointer value (both in the HSWP > > and mmio) suggesting that it is running with the CS-interrupt bit set > > before the powercontext has been reloaded. Make sure the clearing of > > that bit is serialised on reset with the re-enabling of the tasklet. > > > > References: https://bugs.freedesktop.org/show_bug.cgi?id=104262 > > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > > Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx> > > Cc: Michał Winiarski <michal.winiarski@xxxxxxxxx> > > Cc: Mika Kuoppala <mika.kuoppala@xxxxxxxxxxxxxxx> > > --- > > drivers/gpu/drm/i915/i915_gem.c | 6 +++++- > > 1 file changed, 5 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c > > index 5b4cfb20de97..a68fc1240c95 100644 > > --- a/drivers/gpu/drm/i915/i915_gem.c > > +++ b/drivers/gpu/drm/i915/i915_gem.c > > @@ -3089,7 +3089,11 @@ i915_gem_reset_request(struct intel_engine_cs *engine, > > void i915_gem_reset_engine(struct intel_engine_cs *engine, > > struct drm_i915_gem_request *request) > > { > > - engine->irq_posted = 0; > > + /* > > + * Make sure this write is visible before we re-enable the interrupt > > + * handlers on another CPU. > > + */ > > After IRC discussion you could add "because tasklet_enable is only a > compiler barrier, so not enough", or something. Thanks, mentioned that tasklet_enable() resolves to just a compiler barrier which should help us recheck this in future if we stumble over it again. -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
