On Fri, Jan 24, 2025 at 09:31:39AM +0100, Peter Zijlstra wrote: > On Thu, Jan 23, 2025 at 08:42:36PM -0800, Hugh Dickins wrote: > > The changelog of commit b67fbebd4cf9 ("mmu_gather: Force tlb-flush > > VM_PFNMAP vmas") has not helped me either. Nor could I locate any > > discussion (Jann, Linus, Peter, Will?) that led up to it. > > Hmm, that was probably on security -- I should have those mails around > somewhere, I'll see if I can dig them up. Hugh, I've bounced you a copy of Jann's original report on the issue. Subject: unmap_mapping_range() race with munmap() on VM_PFNMAP mappings leads to stale TLB entry