CVE-2025-37964 x86/mm: Eliminate window where TLB flushes may be inadvertently skipped

In the Linux kernel, the following vulnerability has been resolved: x86/mm: Eliminate window where TLB flushes may be inadvertently skipped tl;dr: There is a window in the mm switching code where the new CR3 is set and the CPU should be getting TLB flushes for the new mm. But shouldflushtlb has a...

CVE-2025-37964 x86/mm: Eliminate window where TLB flushes may be inadvertently skipped

In the Linux kernel, the following vulnerability has been resolved: x86/mm: Eliminate window where TLB flushes may be inadvertently skipped tl;dr: There is a window in the mm switching code where the new CR3 is set and the CPU should be getting TLB flushes for the new mm. But shouldflushtlb has a...

CVE-2025-37964

CVE-2025-37964 affects the Linux kernel’s x86/mm path, specifically a window during mm switching where an IPITLB flush could be suppressed. The root cause: should_flush_tlb() could skip TLB flushes between load_new_mm_cr3() and writing loaded_mm, in a window labeled LOADED_MM_SWITCHING. The fix: ...