Annoyingly, struct_mutex was not entirely eliminated from the reset pathway; for reasons of its own, intel_display_resumes() requires struct_mutex to prepare the planes it already captured. To avoid the immediate problem of a deadlock between the struct_mutex and the reset srcu, we have to acquire the reset_lock before struct_mutex in i915_gem_fault(). Now any wait underneath struct_mutex will result us in having to forcibly reset all inflight rendering, less than ideal. Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Mika Kuoppala <mika.kuoppala@xxxxxxxxx> --- drivers/gpu/drm/i915/i915_gem.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index cc88e7974422..62e4df1cbf87 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -1834,9 +1834,15 @@ vm_fault_t i915_gem_fault(struct vm_fault *vmf) wakeref = intel_runtime_pm_get(dev_priv); + srcu = i915_reset_trylock(dev_priv); + if (srcu < 0) { + ret = srcu; + goto err_rpm; + } + ret = i915_mutex_lock_interruptible(dev); if (ret) - goto err_rpm; + goto err_reset; /* Access to snoopable pages through the GTT is incoherent. */ if (obj->cache_level != I915_CACHE_NONE && !HAS_LLC(dev_priv)) { @@ -1885,12 +1891,6 @@ vm_fault_t i915_gem_fault(struct vm_fault *vmf) if (ret) goto err_unpin; - srcu = i915_reset_trylock(dev_priv); - if (srcu < 0) { - ret = srcu; - goto err_fence; - } - /* Finally, remap it using the new GTT offset */ ret = remap_io_mapping(area, area->vm_start + (vma->ggtt_view.partial.offset << PAGE_SHIFT), @@ -1898,7 +1898,7 @@ vm_fault_t i915_gem_fault(struct vm_fault *vmf) min_t(u64, vma->size, area->vm_end - area->vm_start), &ggtt->iomap); if (ret) - goto err_reset; + goto err_fence; /* Mark as being mmapped into userspace for later revocation */ assert_rpm_wakelock_held(dev_priv); @@ -1908,14 +1908,14 @@ vm_fault_t i915_gem_fault(struct vm_fault *vmf) i915_vma_set_ggtt_write(vma); -err_reset: - i915_reset_unlock(dev_priv, srcu); err_fence: i915_vma_unpin_fence(vma); err_unpin: __i915_vma_unpin(vma); err_unlock: mutex_unlock(&dev->struct_mutex); +err_reset: + i915_reset_unlock(dev_priv, srcu); err_rpm: intel_runtime_pm_put(dev_priv, wakeref); i915_gem_object_unpin_pages(obj); -- 2.20.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx