CVE-2025-71078

A Segment Lookaside Buffer (SLB) multi-hit error vulnerability was found in the Linux kernel's PowerPC 64-bit hash MMU implementation. When a process migrates between CPUs without triggering switch_mmu_context() (because prev and next mm_struct are the same), the hardware SLB and software preload cache can become desynchronized. This leads to duplicate SLB entries when the evicted entry is later reloaded, triggering a fatal SLB multi-hit machine check exception.

This vulnerability affects PowerPC 64-bit systems using the hash MMU (not radix). The race requires specific process migration patterns across CPUs during context switches. When triggered, the SLB multi-hit error causes a machine check exception that typically results in system crash. The issue is specific to PowerPC server hardware.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.