When inserting the final level PTE, we check that we are not overflowing the page table (checking that pt_used does not exceed the size of the table). However, we have to allow for every other PTE to be pinned by a simultaneous removal thread (as on remove we bump the pt_used counter before adjusting the table).
Signed-off-by: Chris Wilson <[email protected]> Cc: Mika Kuoppala <[email protected]> --- drivers/gpu/drm/i915/i915_gem_gtt.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index 081c8b79c047..94712d3eb882 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -1112,7 +1112,8 @@ static int __gen8_ppgtt_alloc(struct i915_address_space * const vm, atomic_read(&pt->used)); atomic_add(count, &pt->used); - GEM_BUG_ON(atomic_read(&pt->used) > I915_PDES); + /* All other pdes may be simultaneously removed */ + GEM_BUG_ON(atomic_read(&pt->used) > 2 * I915_PDES); *start += count; } } while (idx++, --len); -- 2.23.0.rc1 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
