From: David Woodhouse <dwmw2@infradead.org>
To: Andy Lutomirski <luto@kernel.org>,
x86@kernel.org, LKML <linux-kernel@vger.kernel.org>
Cc: Borislav Petkov <bp@alien8.de>,
Matt Rickard <matt@softrans.com.au>,
Jason Vas Dias <jason.vas.dias@gmail.com>,
Peter Zijlstra <peterz@infradead.org>,
Andi Kleen <ak@linux.intel.com>
Subject: Re: [PATCH] x86/vdso: Fix vDSO build if a retpoline is emitted
Date: Thu, 16 Aug 2018 21:44:57 +0200 [thread overview]
Message-ID: <1534448697.6862.60.camel@infradead.org> (raw)
In-Reply-To: <c76538cd3afbe19c6246c2d1715bc6a60bd63985.1534448381.git.luto@kernel.org>
[-- Attachment #1: Type: text/plain, Size: 782 bytes --]
On Thu, 2018-08-16 at 12:41 -0700, Andy Lutomirski wrote:
> Currently, if the vDSO ends up containing an indirect branch or
> call, GCC will emit the "external thunk" style of retpoline, and it
> will fail to link.
>
> Fix it by building the vDSO with inline retpoline thunks.
>
> I haven't seen any reports of this triggering on an unpatched
> kernel.
>
> Cc: Matt Rickard <matt@softrans.com.au>
> Cc: Jason Vas Dias <jason.vas.dias@gmail.com>
> Cc: David Woodhouse <dwmw2@infradead.org>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: Andi Kleen <ak@linux.intel.com>
> Fixes: commit 76b043848fd2 ("x86/retpoline: Add initial retpoline support")
> Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Thanks.
[-- Attachment #2: smime.p7s --]
[-- Type: application/x-pkcs7-signature, Size: 5213 bytes --]
next prev parent reply other threads:[~2018-08-16 19:45 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-08-16 19:41 Andy Lutomirski
2018-08-16 19:44 ` David Woodhouse [this message]
2018-08-17 2:45 ` Matthew Rickard
2018-08-20 16:10 ` [tip:x86/urgent] " tip-bot for Andy Lutomirski
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=1534448697.6862.60.camel@infradead.org \
--to=dwmw2@infradead.org \
--cc=ak@linux.intel.com \
--cc=bp@alien8.de \
--cc=jason.vas.dias@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=matt@softrans.com.au \
--cc=peterz@infradead.org \
--cc=x86@kernel.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
all inboxes | Powered by JetHome®