xen-devel.lists.xenproject.org archive mirror
 help / color / mirror / Atom feed
From: Jan Beulich <jbeulich@suse.com>
To: "Roger Pau Monné" <roger.pau@citrix.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>, Wei Liu <wl@xen.org>,
	Ian Jackson <iwj@xenproject.org>,
	"xen-devel@lists.xenproject.org" <xen-devel@lists.xenproject.org>
Subject: Re: [PATCH v3][4.15] x86: mirror compat argument translation area for 32-bit PV
Date: Thu, 25 Feb 2021 10:32:38 +0100	[thread overview]
Message-ID: <c56c115f-10de-35b0-c27c-1930e99d9377@suse.com> (raw)
In-Reply-To: <dbdb045d-42de-af94-64cc-0be7992b80b6@suse.com>

On 25.02.2021 10:30, Jan Beulich wrote:
> Now that we guard the entire Xen VA space against speculative abuse
> through hypervisor accesses to guest memory, the argument translation
> area's VA also needs to live outside this range, at least for 32-bit PV
> guests. To avoid extra is_hvm_*() conditionals, use the alternative VA
> uniformly.
> 
> While this could be conditionalized upon CONFIG_PV32 &&
> CONFIG_SPECULATIVE_HARDEN_GUEST_ACCESS, omitting such extra conditionals
> keeps the code more legible imo.
> 
> Fixes: 4dc181599142 ("x86/PV: harden guest memory accesses against speculative abuse")
> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> Acked-by: Roger Pau Monné <roger.pau@citrix.com>

Roger - I would have dropped an R-b, but I've assumed keeping an A-b
would be fine. Please let me know if this was wrong.

Jan


  reply	other threads:[~2021-02-25  9:32 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-02-25  9:30 [PATCH v3][4.15] x86: mirror compat argument translation area for 32-bit PV Jan Beulich
2021-02-25  9:32 ` Jan Beulich [this message]
2021-02-25 12:52 ` Andrew Cooper
2021-02-25 12:58   ` Jan Beulich

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=c56c115f-10de-35b0-c27c-1930e99d9377@suse.com \
    --to=jbeulich@suse.com \
    --cc=andrew.cooper3@citrix.com \
    --cc=iwj@xenproject.org \
    --cc=roger.pau@citrix.com \
    --cc=wl@xen.org \
    --cc=xen-devel@lists.xenproject.org \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).