Re: [BUG] 2.6.18-rc4-mm3 x86_64-mm-spin-irqs-enabled causes problems

Re: [BUG] 2.6.18-rc4-mm3 x86_64-mm-spin-irqs-enabled causes problems

[Andrew Morton]

On Tue, 29 Aug 2006 16:59:36 -0700
keith mannthey <kmannth@us.ibm.com> wrote:

>   I moved to mm2 to mm3 and had trouble booting again with my hardware.
> In -mm3 the kernel boots but about the time init starts the whole box
> just stops doing anything.  Sysrq works and I dumped the tasks but
> nothing look too far out of place.  
> 
> I did a bisection of -mm3 and found x86_64-mm-spin-irqs-enabled.patch to
> be the cause. 

Yes, Hugh was hitting that today and the following has emerged...

From: Andrew Morton <akpm@osdl.org>

Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 include/asm-x86_64/spinlock.h |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff -puN include/asm-x86_64/spinlock.h~x86_64-mm-spin-irqs-enabled-fix include/asm-x86_64/spinlock.h
--- a/include/asm-x86_64/spinlock.h~x86_64-mm-spin-irqs-enabled-fix
+++ a/include/asm-x86_64/spinlock.h
@@ -51,7 +51,7 @@ static inline void __raw_spin_lock_flags
 {
 	asm volatile(
 		"\n1:\t"
-		LOCK_PREFIX "; decb %0\n\t"
+		LOCK_PREFIX "; decl %0\n\t"
 		"js 2f\n\t"
 		LOCK_SECTION_START("")
 		"2:\t"
@@ -60,7 +60,7 @@ static inline void __raw_spin_lock_flags
 		"sti\n\t"
 		"3:\t"
 		"rep;nop\n\t"
-		"cmpb $0, %0\n\t"
+		"cmpl $0, %0\n\t"
 		"jle 3b\n\t"
 		"cli\n\t"
 		"jmp 1b\n"
_

Re: [BUG] 2.6.18-rc4-mm3 x86_64-mm-spin-irqs-enabled causes problems

[Andi Kleen]

On Wednesday 30 August 2006 01:59, keith mannthey wrote:
> Hello, 
>   I moved to mm2 to mm3 and had trouble booting again with my hardware.
> In -mm3 the kernel boots but about the time init starts the whole box
> just stops doing anything.  Sysrq works and I dumped the tasks but
> nothing look too far out of place.  
> 
> I did a bisection of -mm3 and found x86_64-mm-spin-irqs-enabled.patch to
> be the cause. 

Yes it also broke someone else's box. We know what is broken now,
but the patch is dropped alreayd anyways because it had other issues too.

-Andi