All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Stecklina, Julian" <jsteckli@amazon.de>
To: "sean.j.christopherson@intel.com" <sean.j.christopherson@intel.com>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	"js@alien8.de" <js@alien8.de>,
	"pbonzini@redhat.com" <pbonzini@redhat.com>
Subject: Re: [PATCH v2 2/3] kvm, vmx: move register clearing out of assembly path
Date: Thu, 1 Nov 2018 13:40:29 +0000	[thread overview]
Message-ID: <1541079629.1777.9.camel@amazon.de> (raw)
In-Reply-To: <20181029172608.GB27762@linux.intel.com>

On Mon, 2018-10-29 at 10:26 -0700, Sean Christopherson wrote:
> I think it's a good idea to explicitly call out that clearing the
> GPRs
> is done to prevent speculative use.  Simply stating that we don't
> want
> to let guest register values survive doesn't explain *why*.
> 
> What about:
> 
>         /*
>          * Explicitly clear (in addition to marking them as
> clobbered) all GPRs
>          * that have not been loaded with host state to prevent
> speculatively
>          * using the guest's values.
>          */

Sounds good. I've also updated the commit message for the register
clearing commit. I'll repost the patches.

Julian



Amazon Development Center Germany GmbH
Krausenstr. 38
10117 Berlin
Geschaeftsfuehrer: Christian Schlaeger, Ralf Herbrich
Ust-ID: DE 289 237 879
Eingetragen am Amtsgericht Charlottenburg HRB 149173 B


  reply	other threads:[~2018-11-01 13:40 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-10-29 15:40 [PATCH v2 1/3] kvm, vmx: move CR2 context switch out of assembly path Julian Stecklina
2018-10-29 15:40 ` [PATCH v2 2/3] kvm, vmx: move register clearing " Julian Stecklina
2018-10-29 17:26   ` Sean Christopherson
2018-11-01 13:40     ` Stecklina, Julian [this message]
2018-10-29 15:40 ` [PATCH v2 3/3] kvm, vmx: fix __invvpid style Julian Stecklina
2018-10-29 17:14 ` [PATCH v2 1/3] kvm, vmx: move CR2 context switch out of assembly path Sean Christopherson

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1541079629.1777.9.camel@amazon.de \
    --to=jsteckli@amazon.de \
    --cc=js@alien8.de \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=pbonzini@redhat.com \
    --cc=sean.j.christopherson@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.