On Tue, 2020-05-26 at 22:13 -0700, Sean Christopherson wrote: > On Mon, May 25, 2020 at 09:15:57PM +0800, Brad Campbell wrote: > > > When you mean that KVM is broken after suspend, you mean that you > > > can't > > > start new VMs after suspend, or do VMs that were running before > > > suspend > > > break? I see the later on my machine. I have AMD system though, > > > so most > > > likely this is another bug. > > > > > > Looking at the commit, I suspect that we indeed should set the > > > IA32_FEAT_CTL > > > after resume from ram, since suspend to ram might count as a > > > complete CPU > > > reset. > > > > > > > One of those "I should have clarified that" moments immediately > > after I > > pressed send. I've not tried suspending with a VM running. It's > > "can't start > > new VMs after suspend". > > Don't bother testing suspending with a VM, the only thing that will > be > different is that your system will hang on resume instead when > running a > VM. If there are active VMs, KVM automatically re-enables VMX via > VMXON > after resume, and VMXON is what's faulting. > > Odds are good the firmware simply isn't initializing IA32_FEAT_CTL, > ever. > The kernel handles the boot-time case, but I (obviously) didn't > consider > the suspend case. I'll work on a patch. This is exactly what I was thinking about this as well. Best regards, Maxim Levitsky >
