Linux Kernel Daily: A Nested Guest Security Fix and Cleanup Loop Bugs
Two subsystem pulls landed today, one for KVM and one for kernel probes, and both share a common thread: error and cleanup paths that were skipped or handled incorrectly, including one bug that let a nested guest attack its own host.
Duration: PT2M11S
Episode overview
This episode is a short developer briefing from Linux Kernel Daily.
It explains recent repository work in plain language.
- Show: Linux Kernel Daily
- Published: 2026-07-30T06:01:01Z
- Audio duration: PT2M11S
Transcript excerpt
This excerpt keeps the crawler page concise. Listen to the episode or use the RSS feed for the full update.
Good evening, it's July 30th, 2026, and this is Linux Kernel Daily.
Tonight's top story is a security fix in KVM's AMD virtualization code. And the broader pattern across today's activity is cleanup and error-path handling that either ran too late or didn't run at all.
Start with commit 7d3aae2 from Sean Christopherson. When AVIC, the AMD advanced interrupt controller, is disabled while a nested guest is running, KVM was failing to update the interrupt intercepts for the outer guest. The result: a nested guest could read the host's local APIC state, send arbitrary interrupts, and…
The second theme is incomplete cleanup on error, and it shows up twice in the probes pull, tag "probes fixes," merged in 11028ab. In fprobe registration, commit 8cf2f40 fixes a module reference count leak: when address resolution failed partway through, the code returned early instead of releasing module references…
The common thread: correctness bugs in the paths nobody exercises until something fails, whether that's a partial VM state change or a partial registration.
What's next: expect these to move quickly into stable trees, particularly the AVIC intercept fix given its security impact on nested…
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