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

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] [day] [month] [year] [list]

Date:   Wed, 8 Jul 2020 12:49:17 -0700
From:   Abhishek Bhardwaj <abhishekbh@...gle.com>
To:     Randy Dunlap <rdunlap@...radead.org>
Cc:     LKML <linux-kernel@...r.kernel.org>,
        Anthony Steinhauser <asteinhauser@...gle.com>,
        Borislav Petkov <bp@...en8.de>,
        "H. Peter Anvin" <hpa@...or.com>, Ingo Molnar <mingo@...hat.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>,
        Josh Poimboeuf <jpoimboe@...hat.com>,
        Mark Gross <mgross@...ux.intel.com>,
        Mike Rapoport <rppt@...ux.ibm.com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Pawan Gupta <pawan.kumar.gupta@...ux.intel.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Sean Christopherson <sean.j.christopherson@...el.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Tony Luck <tony.luck@...el.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Waiman Long <longman@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>, kvm@...r.kernel.org,
        x86 <x86@...nel.org>
Subject: Re: [PATCH v4] x86/speculation/l1tf: Add KConfig for setting the L1D
 cache flush mode

On Wed, Jul 8, 2020 at 12:34 PM Randy Dunlap <rdunlap@...radead.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