From 60e94557fff1f5514c7fc4da7ddc2c7a13ffff26 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 23 Jan 2020 22:44:58 +0000 Subject: [PATCH] drm/i915: Check activity on i915_vma after confirming pin_count==0 Only assert that the i915_vma is now idle if and only if no other pins are present. If another user has the i915_vma pinned, they may submit more work to the i915_vma skipping the vm->mutex used to serialise the unbind. We need to wait again, if we want to continue and unbind this vma. However, if we own the i915_vma (we hold the vm->mutex for the unbind and the pin_count is 0), we can assert that the vma remains idle as we unbind. Fixes: 2850748ef876 ("drm/i915: Pull i915_vma_pin under the vm->mutex") Closes: https://gitlab.freedesktop.org/drm/intel/issues/530 Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Reviewed-by: Tvrtko Ursulin Link: https://patchwork.freedesktop.org/patch/msgid/20200123224459.38128-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_vma.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c index 306b951831fe..4999882fbceb 100644 --- a/drivers/gpu/drm/i915/i915_vma.c +++ b/drivers/gpu/drm/i915/i915_vma.c @@ -1202,16 +1202,26 @@ int __i915_vma_unbind(struct i915_vma *vma) if (ret) return ret; - GEM_BUG_ON(i915_vma_is_active(vma)); if (i915_vma_is_pinned(vma)) { vma_print_allocator(vma, "is pinned"); return -EAGAIN; } - GEM_BUG_ON(i915_vma_is_active(vma)); + /* + * After confirming that no one else is pinning this vma, wait for + * any laggards who may have crept in during the wait (through + * a residual pin skipping the vm->mutex) to complete. + */ + ret = i915_vma_sync(vma); + if (ret) + return ret; + if (!drm_mm_node_allocated(&vma->node)) return 0; + GEM_BUG_ON(i915_vma_is_pinned(vma)); + GEM_BUG_ON(i915_vma_is_active(vma)); + if (i915_vma_is_map_and_fenceable(vma)) { /* * Check that we have flushed all writes through the GGTT