Quoting Zhenyu Wang (2019-03-27 09:06:36) > This is to disable semaphore usage when on vGPU for now. Unfortunately > GVT-g hasn't fully enabled semaphore usage yet, so current guest with > semaphore use would cause vGPU failure. > > Although current semaphore failure with vGPU can be simply resolved by > allowing cmd parser to accept MI_SEMAPHORE_WAIT command with address > audit, we're checking general usage of semaphore and how we should > handle it properly for virtualization in consider of function and > security concern. So we decide to request to disable it for now in > guest driver. Once GVT could support it, we would add new compat bit > to turn it on. > > Cc: Kevin Tian <kevin.tian@xxxxxxxxx> > Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> > Signed-off-by: Zhenyu Wang <zhenyuw@xxxxxxxxxxxxxxx> > --- > Note this needs to queue for -next otherwise next kernel i915 as guest > would be broken for GVT. > > drivers/gpu/drm/i915/intel_lrc.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c > index 66bc3cd4e166..50075e24ae03 100644 > --- a/drivers/gpu/drm/i915/intel_lrc.c > +++ b/drivers/gpu/drm/i915/intel_lrc.c > @@ -2315,7 +2315,8 @@ void intel_execlists_set_default_submission(struct intel_engine_cs *engine) > engine->park = NULL; > engine->unpark = NULL; > > - engine->flags |= I915_ENGINE_HAS_SEMAPHORES; > + if (!intel_vgpu_active(engine->i915)) > + engine->flags |= I915_ENGINE_HAS_SEMAPHORES; Fwiw, this will have the desired effect so, Acked-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Just the question remains as this is being used by userspace, sweeping it under the rug might be a bit more difficult. -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
