Re: [Xen-devel] [PATCH v2 2/2] vmx/hap: optimize CR4 trapping

2018-02-16 Thread Razvan Cojocaru
On 02/16/2018 02:39 PM, Razvan Cojocaru wrote: > On 02/16/2018 02:37 PM, Roger Pau Monné wrote: >> On Fri, Feb 16, 2018 at 02:30:55PM +0200, Razvan Cojocaru wrote: >>> On 02/16/2018 02:10 PM, Roger Pau Monne wrote: diff --git a/xen/arch/x86/monitor.c b/xen/arch/x86/monitor.c index f229e69

Re: [Xen-devel] [PATCH v2 2/2] vmx/hap: optimize CR4 trapping

2018-02-16 Thread Razvan Cojocaru
On 02/16/2018 02:37 PM, Roger Pau Monné wrote: > On Fri, Feb 16, 2018 at 02:30:55PM +0200, Razvan Cojocaru wrote: >> On 02/16/2018 02:10 PM, Roger Pau Monne wrote: >>> diff --git a/xen/arch/x86/monitor.c b/xen/arch/x86/monitor.c >>> index f229e69948..4317658c56 100644 >>> --- a/xen/arch/x86/monitor

Re: [Xen-devel] [PATCH v2 2/2] vmx/hap: optimize CR4 trapping

2018-02-16 Thread Roger Pau Monné
On Fri, Feb 16, 2018 at 02:30:55PM +0200, Razvan Cojocaru wrote: > On 02/16/2018 02:10 PM, Roger Pau Monne wrote: > > diff --git a/xen/arch/x86/monitor.c b/xen/arch/x86/monitor.c > > index f229e69948..4317658c56 100644 > > --- a/xen/arch/x86/monitor.c > > +++ b/xen/arch/x86/monitor.c > > @@ -189,10

Re: [Xen-devel] [PATCH v2 2/2] vmx/hap: optimize CR4 trapping

2018-02-16 Thread Razvan Cojocaru
On 02/16/2018 02:10 PM, Roger Pau Monne wrote: > diff --git a/xen/arch/x86/monitor.c b/xen/arch/x86/monitor.c > index f229e69948..4317658c56 100644 > --- a/xen/arch/x86/monitor.c > +++ b/xen/arch/x86/monitor.c > @@ -189,10 +189,11 @@ int arch_monitor_domctl_event(struct domain *d, > ad

[Xen-devel] [PATCH v2 2/2] vmx/hap: optimize CR4 trapping

2018-02-16 Thread Roger Pau Monne
There a bunch of bits in CR4 that should be allowed to be set directly by the guest without requiring Xen intervention, currently this is already done by passing through guest writes into the CR4 used when running in non-root mode, but taking an expensive vmexit in order to do so. xenalyze reports