From: Alex Deucher alexander.deucher@amd.com
If the requested number of DWs on the ring is larger than the size of the ring itself, return an error.
In testing with large VM updates, we've seen crashes when we try and allocate more space on the ring than the total size of the ring without checking.
This prevents the crash but for large VM updates or bo moves of very large buffers, we will need to break the transaction down into multiple batches. I have patches to use IBs for the next kernel.
Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org --- drivers/gpu/drm/radeon/radeon_ring.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-)
diff --git a/drivers/gpu/drm/radeon/radeon_ring.c b/drivers/gpu/drm/radeon/radeon_ring.c index 2430d80..cd72062 100644 --- a/drivers/gpu/drm/radeon/radeon_ring.c +++ b/drivers/gpu/drm/radeon/radeon_ring.c @@ -377,6 +377,9 @@ int radeon_ring_alloc(struct radeon_device *rdev, struct radeon_ring *ring, unsi { int r;
+ /* make sure we aren't trying to allocate more space than there is on the ring */ + if (ndw > (ring->ring_size / 4)) + return -ENOMEM; /* Align requested size with padding so unlock_commit can * pad safely */ ndw = (ndw + ring->align_mask) & ~ring->align_mask;