From: "H. Peter Anvin" <hpa@zytor.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
Peter Zijlstra <peterz@infradead.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
akpm@osdl.org, Rusty Russell <rusty@rustcorp.com.au>,
Glauber de Oliveira Costa <gcosta@redhat.com>,
Jan Beulich <jbeulich@novell.com>, Andi Kleen <ak@suse.de>,
Thomas Gleixner <tglx@linutronix.de>,
pinskia@gcc.gnu.org
Subject: Re: [PATCH] pop previous section in alternative.c
Date: Wed, 09 Apr 2008 17:20:18 -0700 [thread overview]
Message-ID: <47FD5D42.5000603@zytor.com> (raw)
In-Reply-To: <Pine.LNX.4.58.0804091906040.31970@gandalf.stny.rr.com>
Steven Rostedt wrote:
> On Wed, 9 Apr 2008, Steven Rostedt wrote:
>
>> gcc expects all toplevel assembly to return to the original section type.
>> The code in alteranative.c does not do this. This caused some strange bugs
>> in sched-devel where code would end up in the .rodata section and when
>> the kernel sets the NX bit on all .rodata, the kernel would crash when
>> executing this code.
>>
>> This patch adds a .previous marker to return the code back to the
>> original section.
>>
>
> Oh, and this would not be complete without giving Andrew Pinski complete
> credit for telling me it wasn't a gcc bug but a bug in the toplevel asm
> code in the kernel. ;-)
>
In many ways it's kind of silly for this even to be in assembly, since
all it is is a sequence of comma-separated byte values; I guess it was
the easiest way to deal with it given the ".byte" prefix, but still...
-hpa
next prev parent reply other threads:[~2008-04-10 0:26 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-04-09 23:04 [PATCH] pop previous section in alternative.c Steven Rostedt
2008-04-09 23:51 ` Steven Rostedt
2008-04-10 0:20 ` H. Peter Anvin [this message]
2008-04-10 8:47 ` Andi Kleen
2008-04-10 9:46 ` Andy Whitcroft
2008-04-10 14:11 ` Steven Rostedt
2008-04-10 14:41 ` Andi Kleen
2008-04-10 14:43 ` Steven Rostedt
2008-04-10 14:46 ` Linus Torvalds
2008-04-10 14:55 ` Steven Rostedt
2008-04-10 18:40 ` Sam Ravnborg
2008-04-10 15:05 ` Andi Kleen
2008-04-10 15:18 ` Linus Torvalds
2008-04-10 16:07 ` H. Peter Anvin
2008-04-10 16:20 ` Steven Rostedt
2008-04-10 17:07 ` H. Peter Anvin
2008-04-10 17:32 ` Andrew Pinski
2008-04-10 17:53 ` H. Peter Anvin
2008-04-10 17:36 ` Linus Torvalds
2008-04-10 17:52 ` H. Peter Anvin
2008-04-13 15:27 ` Maciej W. Rozycki
2008-04-10 16:10 ` H. Peter Anvin
2008-04-10 7:00 ` Ingo Molnar
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=47FD5D42.5000603@zytor.com \
--to=hpa@zytor.com \
--cc=ak@suse.de \
--cc=akpm@osdl.org \
--cc=gcosta@redhat.com \
--cc=jbeulich@novell.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=peterz@infradead.org \
--cc=pinskia@gcc.gnu.org \
--cc=rostedt@goodmis.org \
--cc=rusty@rustcorp.com.au \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.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 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.