Re: [PATCH v10 11/41] KVM: guest_memfd: Ensure pages are not in use before conversion
"Edgecombe, Rick P" <[email protected]>
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On Thu, 2026-08-13 at 16:20 -0700, Sean Christopherson wrote: > > Hmm, I think we shouldn't upstream a uABI that we don't have line of sight > > to making robust. So it would be good to settle this thread at least. > > This isn't uABI. You're talking about hitting a race condition between one > task converting a page and another faulting in the same page. An NMI, SMI, or > IRQ at just the right/wrong time, especially on a preemptible kernel, could > lead to the same test failures, even if KVM drops the refcount "immediately". Sorry, I wasn't deeply following this thread. I was thinking along the lines of the scenario somehow affecting the uABI decisions around EAGAIN. But just mostly wanted to chime in about the status of the tdx mmu stress test.