Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1507648
| Path | csiph.com!eternal-september.org!feeder.eternal-september.org!aioe.org!gothmog.csi.it!bofh.it!news.nic.it!robomod |
|---|---|
| From | Borislav Petkov <bp@alien8.de> |
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH] x86: Fix export for mcount and __fentry__ |
| Date | Mon, 24 Oct 2016 21:20:02 +0200 |
| Message-ID | <svSWS-3rd-33@gated-at.bofh.it> (permalink) |
| References | <svSNc-3nI-43@gated-at.bofh.it> |
| X-Original-To | Steven Rostedt <rostedt@goodmis.org> |
| MIME-Version | 1.0 |
| Content-Type | text/plain; charset=utf-8 |
| Content-Disposition | inline |
| User-Agent | NeoMutt/20161014 (1.7.1) |
| Sender | robomod@news.nic.it |
| List-ID | <linux-kernel.vger.kernel.org> |
| X-Mailing-List | linux-kernel@vger.kernel.org |
| Approved | robomod@news.nic.it |
| Lines | 29 |
| Organization | linux.* mail to news gateway |
| X-Original-Cc | LKML <linux-kernel@vger.kernel.org>, Nicholas Piggin <npiggin@gmail.com>, Al Viro <viro@ZenIV.linux.org.uk>, Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@kernel.org>, Gabriel C <nix.or.die@gmail.com> |
| X-Original-Date | Mon, 24 Oct 2016 21:17:43 +0200 |
| X-Original-Message-ID | <20161024191743.rsd74w2vev5efcar@pd.tnic> |
| X-Original-References | <20161024150148.4f9d90e4@gandalf.local.home> |
| X-Original-Sender | linux-kernel-owner@vger.kernel.org |
| Xref | csiph.com linux.kernel:1507648 |
Show key headers only | View raw
On Mon, Oct 24, 2016 at 03:01:48PM -0400, Steven Rostedt wrote:
> Commit 784d5699eddc5 ("x86: move exports to actual definitions") removed the
> EXPORT_SYMBOL(__fentry__) and EXPORT_SYMBOL(mcount) from x8664_ksyms_64.c,
> and added EXPORT_SYMBOL(function_hook) in mcount_64.S instead. The problem
> is that function_hook isn't a function at all, but a macro that is defined
> as either mcount or __fentry__ depending on the support from gcc.
>
> Originally, I thought this was a macro issue, like what __stringify()
> is used for. But the problem is a bit deeper. The Makefile.build has
> some magic that does post processing of files to create the CRC
> bindings. It does some searches for EXPORT_SYMBOL() and because it
> finds a macro name and not the actual functions, this causes
> function_hook not to be converted into mcount or __fentry__ and they
> are missed.
>
> Instead of adding more magic to Makefile.build, just add
> EXPORT_SYMBOL() for mcount and __fentry__ where the ifdef is used.
> Since this is assembly and not C, it doesn't require being set after
> the function is defined.
>
> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Tested-by: Borislav Petkov <bp@suse.de>
--
Regards/Gruss,
Boris.
ECO tip #101: Trim your mails when you reply.
Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
[PATCH] x86: Fix export for mcount and __fentry__ Steven Rostedt <rostedt@goodmis.org> - 2016-10-24 21:10 +0200 Re: [PATCH] x86: Fix export for mcount and __fentry__ Borislav Petkov <bp@alien8.de> - 2016-10-24 21:20 +0200 [tip:x86/urgent] x86: Fix export for mcount and __fentry__ tip-bot for Steven Rostedt <tipbot@zytor.com> - 2016-10-26 12:50 +0200
csiph-web