Re: [PATCH] x86,kvm,vmx: Don't trap writes to CR4.TSD

2014-10-22 Thread Paolo Bonzini
On 10/22/2014 09:10 PM, Andy Lutomirski wrote: > On Tue, Oct 7, 2014 at 5:16 PM, Andy Lutomirski wrote: >> CR4.TSD is guest-owned; don't trap writes to it in VMX guests. This >> avoids a VM exit on context switches into or out of a PR_TSC_SIGSEGV >> task. > > Friendly ping. I suspect this got l

Re: [PATCH] x86,kvm,vmx: Don't trap writes to CR4.TSD

2014-10-22 Thread Andy Lutomirski
On Tue, Oct 7, 2014 at 5:16 PM, Andy Lutomirski wrote: > CR4.TSD is guest-owned; don't trap writes to it in VMX guests. This > avoids a VM exit on context switches into or out of a PR_TSC_SIGSEGV > task. Friendly ping. I suspect this got lost in KVM Forum, etc. --Andy > > I think that this fi

[PATCH] x86,kvm,vmx: Don't trap writes to CR4.TSD

2014-10-07 Thread Andy Lutomirski
CR4.TSD is guest-owned; don't trap writes to it in VMX guests. This avoids a VM exit on context switches into or out of a PR_TSC_SIGSEGV task. I think that this fixes an unintentional side-effect of: 4c38609ac569 KVM: VMX: Make guest cr4 mask more conservative Signed-off-by: Andy Lutomirski