From: Keith Owens <kaos@ocs.com.au>
To: linux-kernel@vger.kernel.org
Subject: [patch 2.6.19-rc6] Stop gcc 4.1.0 optimizing wait_hpet_tick away
Date: Wed, 29 Nov 2006 13:22:03 +1100 [thread overview]
Message-ID: <19133.1164766923@kao2.melbourne.sgi.com> (raw)
Compiling 2.6.19-rc6 with gcc version 4.1.0 (SUSE Linux),
wait_hpet_tick is optimized away to a never ending loop and the kernel
hangs on boot in timer setup.
0000001a <wait_hpet_tick>:
1a: 55 push %ebp
1b: 89 e5 mov %esp,%ebp
1d: eb fe jmp 1d <wait_hpet_tick+0x3>
This is not a problem with gcc 3.3.5. Adding barrier() calls to
wait_hpet_tick does not help, making the variables volatile does.
Signed-off-by: Keith Owens <kaos@ocs.com.au>
---
arch/i386/kernel/time_hpet.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
Index: linux-2.6/arch/i386/kernel/time_hpet.c
===================================================================
--- linux-2.6.orig/arch/i386/kernel/time_hpet.c
+++ linux-2.6/arch/i386/kernel/time_hpet.c
@@ -51,7 +51,7 @@ static void hpet_writel(unsigned long d,
*/
static void __devinit wait_hpet_tick(void)
{
- unsigned int start_cmp_val, end_cmp_val;
+ unsigned volatile int start_cmp_val, end_cmp_val;
start_cmp_val = hpet_readl(HPET_T0_CMP);
do {
next reply other threads:[~2006-11-29 2:22 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-11-29 2:22 Keith Owens [this message]
2006-11-29 3:08 ` [patch 2.6.19-rc6] Stop gcc 4.1.0 optimizing wait_hpet_tick away Nicholas Miell
2006-11-29 3:56 ` Keith Owens
2006-11-29 4:04 ` David Miller
2006-11-29 4:30 ` Keith Owens
2006-11-29 4:57 ` Nicholas Miell
2006-11-30 1:04 ` David Schwartz
2006-12-01 5:50 ` Kyle Moffett
2006-12-01 11:24 ` David Schwartz
2006-12-01 12:08 ` Kyle Moffett
2006-12-01 13:52 ` David Schwartz
2006-12-02 9:02 ` Jan Engelhardt
2006-12-01 12:31 ` Andreas Schwab
2006-12-01 14:03 ` David Schwartz
2006-12-02 10:39 ` Kyle Moffett
2006-12-03 4:29 ` David Schwartz
2006-12-07 14:02 ` Kyle Moffett
2006-12-08 4:22 ` David Schwartz
2006-11-29 9:08 ` Jakub Jelinek
2006-11-29 20:14 ` Willy Tarreau
2006-12-01 5:05 ` Andrew Morton
2006-12-01 5:14 ` Keith Owens
2006-12-01 5:26 ` Willy Tarreau
2006-12-01 6:32 ` Keith Owens
2006-12-01 7:28 ` Willy Tarreau
2006-12-01 7:57 ` Jakub Jelinek
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=19133.1164766923@kao2.melbourne.sgi.com \
--to=kaos@ocs.com.au \
--cc=linux-kernel@vger.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;
as well as URLs for NNTP newsgroup(s).