CVE-2026-64172

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> KVM: SVM: Disable AVIC IPI virtualization on Hygon Family 18h (erratum #1235)<br /> <br /> Hygon Family 18h CPUs are derived from AMD Family 17h (Zen1) silicon and<br /> share the same erratum #1235: hardware may read a stale IsRunning=1 bit<br /> during ICR write emulation and silently fail to generate an<br /> AVIC_IPI_FAILURE_TARGET_NOT_RUNNING VM-Exit on the sending vCPU.<br /> <br /> The absence of the VM-Exit causes KVM to miss the required wakeup of<br /> blocking target vCPUs, leading to hung vCPUs and unbounded delays in<br /> guest execution.<br /> <br /> Extend the existing AMD Family 17h erratum #1235 workaround to also cover<br /> Hygon Family 18h. With IPI virtualization disabled, KVM never sets<br /> IsRunning=1 in the Physical ID table, so every non-self IPI generates a<br /> VM-Exit and is correctly emulated.