Re: [RFC PATCH V5 15/15] x86/sev: Fix interrupt exit code paths from #HV exception

[Tianyu Lan]

On 5/1/2023 9:02 AM, Tom Lendacky wrote:
> > From: Ashish Kalra <ashish.kalra@xxxxxxx>
> >
> > Add checks in interrupt exit code paths in case of returns
> > to user mode to check if currently executing the #HV handler
> > then don't follow the irqentry_exit_to_user_mode path as
> > that can potentially cause the #HV handler to be
> > preempted and rescheduled on another CPU. Rescheduled #HV
> > handler on another cpu will cause interrupts to be handled
> > on a different cpu than the injected one, causing
> > invalid EOIs and missed/lost guest interrupts and
> > corresponding hangs and/or per-cpu IRQs handled on
> > non-intended cpu.
> >
> > Signed-off-by: Ashish Kalra <ashish.kalra@xxxxxxx>
>
> This should be merged into one of the appropriate #HV patches and just 
> add Ashish with a Co-developed-by: tag where appropriate. This would be 
> appropriate as a separate only if discovered after the series was merged.

Sure. Will update in the next version.