Quoting Mika Kuoppala (2019-02-19 13:07:08) > Chris Wilson <ch...@chris-wilson.co.uk> writes: > > > Introduce a new ABI method for detecting a wedged driver by reporting > > -EIO from DRM_IOCTL_I915_GEM_CONTEXT_CREATE. > > Need more on the 'why' department. What is lacking with > the method of submitting and noticing the wedged? > > Also detecting banned from wedged is not trivial.
The biggest problem is our transient wedging, where we use i915_gem_set_wedged() to cancel inflight rendering to avoid a deadlock during reset. That is an issue here as we may submit and see -EIO even though the driver isn't strictly terminally wedged and may reset. We've even seen that once in practice, https://bugs.freedesktop.org/show_bug.cgi?id=109580. Hmm, pre-existing problem requiring more general solution. I'm thinking along the lines of if (i915_terminally_wedged()) return i915_reset_backoff() ? -EAGAIN : -EIO; Joy. /o\ ret = i915_reset_backoff(); static int i915_reset_backoff() { unsigned long flags = READ_ONCE(error->flags); if (!(flags & WEDGED)) return 0; if (flags & BACKOFF) return -EAGAIN; return -EIO; } Seems eerily familiar, like a full circle. -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
