CVE-2026-63863: drm/gpusvm: Fix unbalanced unlock in drm_gpusvm_scan_mm()
In the Linux kernel, the following vulnerability has been resolved:
drm/gpusvm: Fix unbalanced unlock in drmgpusvmscanmm()
There is a unbalanced lock/unlock to gpusvm notifier lock: [ 931.045868] ===================================== [ 931.046509] WARNING: bad unlock balance detected! [ 931.047149] 6.19.0-rc6+xe- #9 Tainted: G U [ 931.048150] ------------------------------------- [ 931.048790] kworker/u5:0/51 is trying to release lock (&gpusvm->notifierlock) at: [ 931.049801] [<ffffffffa090c0d8>] drmgpusvmscanmm+0x188/0x460 [drmgpusvmhelper] [ 931.050802] but there are no more locks to release! [ 931.051463]
The drmgpusvmnotifierunlock() sits under errfree label and the first jump to errfree is just before calling the drmgpusvmnotifierlock() causing unbalanced unlock.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-63863?
CVE-2026-63863 has a high severity rating of 8.8.
What is the impact of CVE-2026-63863?
CVE-2026-63863 can lead to denial of service due to unbalanced locking in the Linux kernel’s GPU virtual memory management.
How do I fix CVE-2026-63863?
To fix CVE-2026-63863, update to the patched version of the Linux kernel that addresses the unbalanced unlock issue.
Which software is affected by CVE-2026-63863?
CVE-2026-63863 affects the Linux kernel and specifically its handling of GPU virtual memory.
When was CVE-2026-63863 published?
CVE-2026-63863 was published on July 19, 2026.