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Message-ID: <9945dbf586d8738b7cf0af53bfb760da9eb9e882.camel@intel.com>
Subject: Re: [PATCH v7 041/102] KVM: VMX: Introduce test mode related to EPT
 violation VE
From:   Kai Huang <kai.huang@intel.com>
To:     Isaku Yamahata <isaku.yamahata@gmail.com>
Cc:     isaku.yamahata@intel.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>
Date:   Wed, 20 Jul 2022 17:13:08 +1200
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On Tue, 2022-07-19 at 07:49 -0700, Isaku Yamahata wrote:
> On Fri, Jul 08, 2022 at 02:23:43PM +1200,
> Kai Huang <kai.huang@intel.com> wrote:
>=20
> > On Mon, 2022-06-27 at 14:53 -0700, isaku.yamahata@intel.com wrote:
> > > From: Isaku Yamahata <isaku.yamahata@intel.com>
> > >=20
> > > To support TDX, KVM is enhanced to operate with #VE.  For TDX, KVM pr=
ograms
> > > to inject #VE conditionally and set #VE suppress bit in EPT entry.  F=
or VMX
> > > case, #VE isn't used.  If #VE happens for VMX, it's a bug.  To be
> > > defensive (test that VMX case isn't broken), introduce option
> > > ept_violation_ve_test and when it's set, set error.
> >=20
> > I don't see why we need this patch.  It may be helpful during your test=
, but why
> > do we need this patch for formal submission?
> >=20
> > And for a normal guest, what prevents one vcpu from sending #VE IPI to =
another
> > vcpu?
>=20
> Paolo suggested it as follows.  Maybe it should be kernel config.
> (I forgot to add suggested-by. I'll add it)
>=20
> https://lore.kernel.org/lkml/84d56339-4a8a-6ddb-17cb-12074588ba9c@redhat.=
com/
>=20
> >=20

OK.  But can we assume a normal guest won't sending #VE IPI?