https://bugzilla.kernel.org/show_bug.cgi?id=216177 --- Comment #4 from Sean Christopherson (seanjc@xxxxxxxxxx) --- On Tue, Jun 28, 2022, bugzilla-daemon@xxxxxxxxxx wrote: > https://bugzilla.kernel.org/show_bug.cgi?id=216177 > > --- Comment #3 from Yang Lixiao (lixiao.yang@xxxxxxxxx) --- > (In reply to Nadav Amit from comment #2) > > > On Jun 27, 2022, at 5:28 PM, bugzilla-daemon@xxxxxxxxxx wrote: > > > > > > https://bugzilla.kernel.org/show_bug.cgi?id=216177 > > > > > > Sean Christopherson (seanjc@xxxxxxxxxx) changed: > > > > > > What |Removed |Added > > > > > > ---------------------------------------------------------------------------- > > > CC| |seanjc@xxxxxxxxxx > > > > > > --- Comment #1 from Sean Christopherson (seanjc@xxxxxxxxxx) --- > > > It's vmx_preemption_timer_expiry_test, which is known to be flaky (though > > > IIRC > > > it's KVM that's at fault). > > > > > > Test suite: vmx_preemption_timer_expiry_test > > > FAIL: Last stored guest TSC (28067103426) < TSC deadline (28067086048) > > > > For the record: > > > > https://lore.kernel.org/kvm/D121A03E-6861-4736-8070-5D1E4FEE1D32@xxxxxxxxx/ > > Thanks for your reply. So this is a KVM bug, and you have sent a patch to kvm > to fix this bug, right? No, AFAIK no one has posted a fix. If it's the KVM issue I'm thinking of, the fix is non-trivial. It'd require scheduling a timer in L0 with a deadline shorter than what L1 requests when emulating the VMX timer, and then busy waiting in L0 if the host timer fires early. KVM already does this for e.g. L1's TSC deadline timer. That code would need to be adapated for the nested VMX preemption timer. -- You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.
