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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240701084646.268bfc86@jacob-builder>
Date: Mon, 1 Jul 2024 08:46:46 -0700
From: Jacob Pan <jacob.jun.pan@...ux.intel.com>
To: Zeng Guang <guang.zeng@...el.com>
Cc: X86 Kernel <x86@...nel.org>, Sean Christopherson <seanjc@...gle.com>,
 LKML <linux-kernel@...r.kernel.org>, Thomas Gleixner <tglx@...utronix.de>,
 Dave Hansen <dave.hansen@...el.com>, "H. Peter Anvin" <hpa@...or.com>, Ingo
 Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>, Xin Li
 <xin3.li@...el.com>, linux-perf-users@...r.kernel.org, Peter Zijlstra
 <peterz@...radead.org>, Paolo Bonzini <pbonzini@...hat.com>, Tony Luck
 <tony.luck@...el.com>, Andy Lutomirski <luto@...nel.org>, acme@...nel.org,
 kan.liang@...ux.intel.com, Andi Kleen <andi.kleen@...el.com>, "Mehta,
 Sohil" <sohil.mehta@...el.com>, jacob.jun.pan@...ux.intel.com
Subject: Re: [PATCH v3 07/11] KVM: VMX: Handle NMI Source report in VM exit

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

> On 6/29/2024 4:18 AM, Jacob Pan wrote:
> > From: Zeng Guang <guang.zeng@...el.com>
> >
> > 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@...el.com>
> > Signed-off-by: Jacob Pan <jacob.jun.pan@...ux.intel.com>
> > ---
> >   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