Subject: Re: Next April 28: boot failure on PowerPC with SLQB

From: Nick Piggin <[email-masked]>
Date: Thu, 30 Apr 2009 08:41:27 +0200

On Thu, Apr 30, 2009 at 11:06:36AM +0530, Sachin Sant wrote:
> Nick Piggin wrote:
> >Well kmalloc is failing. It should not be though, even if the
> >current node is offline, it should be able to fall back to other
> >nodes. Stephen's trace indicates the same thing.
> >
> >Could you try the following patch please, and capture the output
> >it generates?
> With this patch i don't get any extra information other that what is 
> already reported.
> Have attached the boot log captured using loglevel=8 mminit_loglevel=4 
> options.

Hmm, forget that. Actually my last patch had a silly mistake because I
forgot MAX_ORDER shift is applied to PAGE_SIZE, rather than 1. So
kmalloc(PAGE_SIZE) was failing as too large.

This patch should do the trick I hope.

Thanks,
Nick
---
 include/linux/slqb_def.h |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Index: linux-2.6/include/linux/slqb_def.h
===================================================================
--- linux-2.6.orig/include/linux/slqb_def.h
+++ linux-2.6/include/linux/slqb_def.h
@@ -172,7 +172,8 @@ struct kmem_cache {
 #endif
 
 #define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE)
-#define KMALLOC_SHIFT_SLQB_HIGH (PAGE_SHIFT + 9)
+#define KMALLOC_SHIFT_SLQB_HIGH (PAGE_SHIFT + 			\
+				 ((9 <= (MAX_ORDER - 1)) ? 9 : (MAX_ORDER - 1)))
 
 extern struct kmem_cache kmalloc_caches[KMALLOC_SHIFT_SLQB_HIGH + 1];
 extern struct kmem_cache kmalloc_caches_dma[KMALLOC_SHIFT_SLQB_HIGH + 1];