In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Fix spurious warning for benign stage 2 teardown race kvmtool was… (CVE-2026-98468)

The vulnerability involves a benign race in the Linux kernel's KVM arm64 code during stage 2 page table teardown. When multiple threads concurrently manipulate stage 2 page tables, a spurious warning is triggered due to a race condition between migration and release notifications. Specifically, the warning occurs when __unmap_stage2_range() encounters an -EINVAL return from stage2_apply_range() caused by concurrent teardown of page tables. The fix modifies stage2_apply_range() to no longer treat concurrent page table teardown on lock release as an error, preventing the spurious WARN_ON() while maintaining warnings for other error conditions. This issue only affects the warning mechanism and does not indicate a functional failure or security compromise.

This vulnerability causes spurious kernel warnings during nested virtualization operations on arm64 platforms under memory pressure, which may confuse system administrators or automated monitoring systems. There is no indication of functional impact, data corruption, or security compromise. The race is benign and handled correctly by the kernel, with the fix improving log clarity.

A fix is available that updates the kernel code to suppress the spurious warning. Users should apply the official Linux kernel update that includes this patch to avoid misleading warnings. No other mitigation is required as the race is benign and does not affect system security or stability.