Re: [PATCH v4] x86/speculation/l1tf: Add KConfig for setting the L1D cache flush mode

From: Abhishek Bhardwaj <abhishekbh@google.com>
To: Randy Dunlap <rdunlap@infradead.org>
Cc: LKML <linux-kernel@vger.kernel.org>,
	Anthony Steinhauser <asteinhauser@google.com>,
	Borislav Petkov <bp@alien8.de>, "H. Peter Anvin" <hpa@zytor.com>,
	Ingo Molnar <mingo@redhat.com>, Jim Mattson <jmattson@google.com>,
	Joerg Roedel <joro@8bytes.org>,
	Josh Poimboeuf <jpoimboe@redhat.com>,
	Mark Gross <mgross@linux.intel.com>,
	Mike Rapoport <rppt@linux.ibm.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Pawan Gupta <pawan.kumar.gupta@linux.intel.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Sean Christopherson <sean.j.christopherson@intel.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Tony Luck <tony.luck@intel.com>,
	Vitaly Kuznetsov <vkuznets@redhat.com>,
	Waiman Long <longman@redhat.com>,
	Wanpeng Li <wanpengli@tencent.com>,
	kvm@vger.kernel.org, x86 <x86@kernel.org>
Subject: Re: [PATCH v4] x86/speculation/l1tf: Add KConfig for setting the L1D cache flush mode
Date: Wed, 8 Jul 2020 12:49:17 -0700	[thread overview]
Message-ID: <CA+noqohUFoCQdRKLTtGXOB=GAKYO5Er=-EVpOMowEufB9dnk_g@mail.gmail.com> (raw)
In-Reply-To: <06f15327-f346-fb8d-cc8e-8e12c398324d@infradead.org>

On Wed, Jul 8, 2020 at 12:34 PM Randy Dunlap <rdunlap@infradead.org> wrote:
>
> Hi again,
>
> On 7/8/20 12:25 PM, Abhishek Bhardwaj wrote:
> > diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
> > index b277a2db62676..1f85374a0b812 100644
> > --- a/arch/x86/kvm/Kconfig
> > +++ b/arch/x86/kvm/Kconfig
> > @@ -107,4 +107,17 @@ config KVM_MMU_AUDIT
> >        This option adds a R/W kVM module parameter 'mmu_audit', which allows
> >        auditing of KVM MMU events at runtime.
> >
> > +config KVM_VMENTRY_L1D_FLUSH
> > +     int "L1D cache flush settings (1-3)"
> > +     range 1 3
> > +     default "2"
> > +     depends on KVM && X86_64
> > +     help
> > +      This setting determines the L1D cache flush behavior before a VMENTER.
> > +      This is similar to setting the option / parameter to
> > +      kvm-intel.vmentry_l1d_flush.
> > +      1 - Never flush.
> > +      2 - Conditionally flush.
> > +      3 - Always flush.
> > +
> >  endif # VIRTUALIZATION
>
> If you do a v5, the help text lines (under "help") should be indented
> with one tab + 2 spaces according to Documentation/process/coding-style.rst.

Apologies for missing this. Fixed in v5 -
https://lkml.org/lkml/2020/7/8/1369

>
> --
> ~Randy
>


-- 
Abhishek