lkml.org 
[lkml]   [2006]   [Nov]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[patch 2.6.19-rc6] Stop gcc 4.1.0 optimizing wait_hpet_tick away
Date
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 {
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-11-29 03:27    [W:0.115 / U:5.692 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site