Displaying 2 results from an estimated 2 matches for "msr_mcg_status".
2020 Jun 23
1
Should SEV-ES #VC use IST? (Re: [PATCH] Allow RDTSC and RDTSCP from userspace)
...n only be handled on a best-effort basis, as
>> #MC could happen anytime, also while already executing the #MC handler.
> I think the hardware has a MCE-mask bit somewhere. Flaky though because
> clearing it isn't 'atomic' with IRET, so there's a 'funny' window.
MSR_MCG_STATUS.MCIP, and yes - any #MC before that point will
immediately Shutdown.? Any #MC between that point and IRET will clobber
its IST stack and end up sad.
> It also interacts really bad with the NMI handler. If we get an #MC
> early in the NMI, where we hard-rely on the NMI-mask being set to set-u...
2020 Jun 23
2
Should SEV-ES #VC use IST? (Re: [PATCH] Allow RDTSC and RDTSCP from userspace)
On Tue, Jun 23, 2020 at 03:03:22PM +0200, Peter Zijlstra wrote:
> On Tue, Jun 23, 2020 at 02:12:37PM +0200, Joerg Roedel wrote:
> > On Tue, Jun 23, 2020 at 01:50:14PM +0200, Peter Zijlstra wrote:
> > > If SNP is the sole reason #VC needs to be IST, then I'd strongly urge
> > > you to only make it IST if/when you try and make SNP happen, not before.
> >
>