Description

In the Linux kernel, the following vulnerability has been resolved: x86/mm: Fix SMP ordering in switch_mm_irqs_off() Stephen noted that it is possible to not have an smp_mb() between the loaded_mm store and the tlb_gen load in switch_mm(), meaning the ordering against flush_tlb_mm_range() goes out the window, and it becomes possible for switch_mm() to not observe a recent tlb_gen update and fail to flush the TLBs. [ dhansen: merge conflict fixed by Ingo ]

References 2

• git.kernel.org https://git.kernel.org/stable/c/0fe5e3f5fb75c5d88dad24dece3ee75e9d87adeb
• git.kernel.org https://git.kernel.org/stable/c/83b0177a6c4889b3a6e865da5e21b2c9d97d0551

Remediation