Received-SPF: pass (google.com: domain of linux-kernel+bounces-213851-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.80.249 as permitted sender) client-ip=147.75.80.249;
Date: Thu, 13 Jun 2024 11:38:13 -0700
In-Reply-To: <608b37dbc59a80d32719c8fde8b6979a2b839e10.camel@intel.com>
Precedence: bulk
Mime-Version: 1.0
References: <20240207172646.3981-1-xin3.li@intel.com> <608b37dbc59a80d32719c8fde8b6979a2b839e10.camel@intel.com>
Message-ID: <Zms8lRn20MGVVN9h@google.com>
Subject: Re: [PATCH v2 00/25] Enable FRED with KVM VMX
From: Sean Christopherson <seanjc@google.com>
To: Shan Kang <shan.kang@intel.com>
Cc: Xin3 Li <xin3.li@intel.com>, "kvm@vger.kernel.org" <kvm@vger.kernel.org>, 
	"linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>, 
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, 
	"linux-kselftest@vger.kernel.org" <linux-kselftest@vger.kernel.org>, "corbet@lwn.net" <corbet@lwn.net>, 
	"x86@kernel.org" <x86@kernel.org>, 
	"dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com>, "vkuznets@redhat.com" <vkuznets@redhat.com>, 
	"bp@alien8.de" <bp@alien8.de>, "mingo@redhat.com" <mingo@redhat.com>, 
	"tglx@linutronix.de" <tglx@linutronix.de>, "hpa@zytor.com" <hpa@zytor.com>, 
	"pbonzini@redhat.com" <pbonzini@redhat.com>, "peterz@infradead.org" <peterz@infradead.org>, 
	"shuah@kernel.org" <shuah@kernel.org>, Ravi V Shankar <ravi.v.shankar@intel.com>, 
	"xin@zytor.com" <xin@zytor.com>
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: quoted-printable

On Wed, Mar 27, 2024, Shan Kang wrote:
> On Wed, 2024-02-07 at 09:26 -0800, Xin Li wrote:
> > This patch set enables the Intel flexible return and event delivery
> > (FRED) architecture with KVM VMX to allow guests to utilize FRED.
> >=20
> We tested this FRED KVM patch set on a 7th Intel(R) Core(TM) CPU and the =
Intel=20
> Simics=C2=AE Simulator with the following four configurations:

That likely provides coverage for the happy cases, but I doubt it provides =
negative
testing, e.g. for VM-Enter consistency checks.  KVM-Unit-Tests are currentl=
y the
best choice for concistency checks (unfortunately).

And given the insanity of event re-injection, KVM selftests needs a dedicat=
ed test
for that, and another for the interactions with nVMX, e.g. a la svm_nested_=
soft_inject_test.c.

I haven't looked too closely at the selftest that's already provided, but m=
y
suspicion is that we'll want multiple tests, or alternatively one test that
uses KVM_ONE_VCPU_TEST_SUITE().