linux-kernel - Re: [RFC PATCH 5/6] x86/Hyper-V: Not use auto-eoi when Secure AVIC is available

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: <CAMvTesAmvVCQn47ZV+k9r0qNape_5zcCJ_Fwj+kXNi-Rby_U7A@mail.gmail.com>
Date: Fri, 16 May 2025 23:53:32 +0800
From: Tianyu Lan <ltykernel@...il.com>
To: Michael Kelley <mhklinux@...look.com>
Cc: "kys@...rosoft.com" <kys@...rosoft.com>, "haiyangz@...rosoft.com" <haiyangz@...rosoft.com>, 
	"wei.liu@...nel.org" <wei.liu@...nel.org>, "decui@...rosoft.com" <decui@...rosoft.com>, 
	"tglx@...utronix.de" <tglx@...utronix.de>, "mingo@...hat.com" <mingo@...hat.com>, "bp@...en8.de" <bp@...en8.de>, 
	"dave.hansen@...ux.intel.com" <dave.hansen@...ux.intel.com>, "x86@...nel.org" <x86@...nel.org>, 
	"hpa@...or.com" <hpa@...or.com>, "Neeraj.Upadhyay@....com" <Neeraj.Upadhyay@....com>, 
	"yuehaibing@...wei.com" <yuehaibing@...wei.com>, "kvijayab@....com" <kvijayab@....com>, 
	"jacob.jun.pan@...ux.intel.com" <jacob.jun.pan@...ux.intel.com>, "jpoimboe@...nel.org" <jpoimboe@...nel.org>, 
	"tiala@...rosoft.com" <tiala@...rosoft.com>, 
	"linux-hyperv@...r.kernel.org" <linux-hyperv@...r.kernel.org>, 
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [RFC PATCH 5/6] x86/Hyper-V: Not use auto-eoi when Secure AVIC is available

On Thu, May 15, 2025 at 12:54 AM Michael Kelley <mhklinux@...look.com> wrote:
>
> From: Tianyu Lan <ltykernel@...il.com> Sent: Tuesday, May 6, 2025 6:07 AM
> >
>
> For the patch Subject, use:
>
> x86/hyperv: Don't use auto-EOI when Secure AVIC is available
>
> > Hyper-V doesn't support auto-eoi with Secure AVIC.
> > So Enable HV_DEPRECATING_AEOI_RECOMMENDED flag
>
> s/Enable/enable/
> > to force to write eoi register after handling interrupt.
>
> "to force writing the EOI register after handling an interrupt."
>
> >
> > Signed-off-by: Tianyu Lan <tiala@...rosoft.com>
> > ---
> >  arch/x86/kernel/cpu/mshyperv.c | 3 +++
> >  1 file changed, 3 insertions(+)
> >
> > diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
> > index 3e2533954675..fbe45b5e9790 100644
> > --- a/arch/x86/kernel/cpu/mshyperv.c
> > +++ b/arch/x86/kernel/cpu/mshyperv.c
> > @@ -463,6 +463,9 @@ static void __init ms_hyperv_init_platform(void)
> >
> >       hv_identify_partition_type();
> >
> > +     if (cc_platform_has(CC_ATTR_SNP_SECURE_AVIC))
> > +             ms_hyperv.hints |= HV_DEPRECATING_AEOI_RECOMMENDED;
> > +
>
> Shouldn't Hyper-V already be setting this flag if it is offering Secure AVIC
> to guests? I guess it doesn't hurt to do this in the Linux code, but it seems
> like it should be Hyper-V's responsibility.
>

OK. I will double check from OpenHCL side.



-- 
Thanks
Tianyu Lan