https://bugs.freedesktop.org/show_bug.cgi?id=104082
--- Comment #41 from Jean Delvare jdelvare@suse.de --- Bah, I spoke too fast. Even with commit 9e7f06c8beee ("swiotlb: fix unexpected swiotlb_alloc_coherent failures") backported, I end up seeing the backtraces again, after several hours. So that commit helps but doesn't solve the problem. It seems there are at least 3 different bugs leading to the same problem.