Description
In the Linux kernel, the following vulnerability has been resolved: xen: speed up grant-table reclaim When a grant entry is still in use by the remote domain, Linux must put it on a deferred list. Normally, this list is very short, because the PV network and block protocols expect the backend to unmap the grant first. However, Qubes OS's GUI protocol is subject to the constraints of the X Window System, and as such winds up with the frontend unmapping the window first. As a result, the list can grow very large, resulting in a massive memory leak and eventual VM freeze. To partially solve this problem, make the number of entries that the VM will attempt to free at each iteration tunable. The default is still 10, but it can be overridden via a module parameter. This is Cc: stable because (when combined with appropriate userspace changes) it fixes a severe performance and stability problem for Qubes OS users.
Product status
569ca5b3f94cd0b3295ec5943aa457cf4a4f6a3a (git) before cd1a8952ff529adc210e62306849fd6f256608c0
569ca5b3f94cd0b3295ec5943aa457cf4a4f6a3a (git) before c76d96c555895ac602c1587b001e5cf656abc371
569ca5b3f94cd0b3295ec5943aa457cf4a4f6a3a (git) before c04e9894846c663f3278a414f34416e6e45bbe68
3.5
Any version before 3.5
6.1.43 (semver)
6.4.8 (semver)
6.5 (original_commit_for_fix)
References
git.kernel.org/...c/cd1a8952ff529adc210e62306849fd6f256608c0
git.kernel.org/...c/c76d96c555895ac602c1587b001e5cf656abc371
git.kernel.org/...c/c04e9894846c663f3278a414f34416e6e45bbe68