Description
In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Disable AVIC IPI virtualization on Hygon Family 18h (erratum #1235) Hygon Family 18h CPUs are derived from AMD Family 17h (Zen1) silicon and share the same erratum #1235: hardware may read a stale IsRunning=1 bit during ICR write emulation and silently fail to generate an AVIC_IPI_FAILURE_TARGET_NOT_RUNNING VM-Exit on the sending vCPU. The absence of the VM-Exit causes KVM to miss the required wakeup of blocking target vCPUs, leading to hung vCPUs and unbounded delays in guest execution. Extend the existing AMD Family 17h erratum #1235 workaround to also cover Hygon Family 18h. With IPI virtualization disabled, KVM never sets IsRunning=1 in the Physical ID table, so every non-self IPI generates a VM-Exit and is correctly emulated.
Affected products
linux: linux kernel
References3
Metrics
- CVSS 3.1
-
7.1
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 9 · as of 14 November 2026
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