Re: [PATCH v3 07/11] KVM: VMX: Handle NMI Source report in VM exit

[Jacob Pan]

On Sun, 30 Jun 2024 21:04:18 +0800, Zeng Guang <guang.zeng@xxxxxxxxx> wrote:

> On 6/29/2024 4:18 AM, Jacob Pan wrote:
> > From: Zeng Guang <guang.zeng@xxxxxxxxx>
> >
> > If the "NMI exiting" VM-execution control is 1, the value of the 16-bit
> > NMI source vector is saved in the exit-qualification field in the VMCS
> > when VM exits occur on CPUs that support NMI source.
> >
> > KVM that is aware of NMI-source reporting will push the bitmask of NMI
> > source vectors as the exceptoin event data field on the stack for then
> > entry of FRED exception. Subsequently, the host NMI exception handler
> > is invoked which will process NMI source information in the event data.
> > This operation is independent of vCPU FRED enabling status.
> >
> > Signed-off-by: Zeng Guang <guang.zeng@xxxxxxxxx>
> > Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
> > ---
> >   arch/x86/entry/entry_64_fred.S |  2 +-
> >   arch/x86/kvm/vmx/vmx.c         | 11 ++++++++---
> >   2 files changed, 9 insertions(+), 4 deletions(-)
> >
> > diff --git a/arch/x86/entry/entry_64_fred.S
> > b/arch/x86/entry/entry_64_fred.S index a02bc6f3d2e6..0d934a3fcaf8 100644
> > --- a/arch/x86/entry/entry_64_fred.S
> > +++ b/arch/x86/entry/entry_64_fred.S
> > @@ -92,7 +92,7 @@ SYM_FUNC_START(asm_fred_entry_from_kvm)
> >   	 * +--------+-----------------+
> >   	 */
> >   	push $0				/* Reserved, must be 0
> > */
> > -	push $0				/* Event data, 0 for
> > IRQ/NMI */
> > +	push %rsi			/* Event data for IRQ/NMI */
> >   	push %rdi			/* fred_ss handed in by the
> > caller */ push %rbp
> >   	pushf  
> Move this part to previous patch as it changes the common FRED api and 
> prepares for nmi handling in case of nmi
> source enabled in this patch.
You are right, will do.
>  [...]  


Thanks,

Jacob