Re: 2.6.15-rc1-git crashes in kswapd

[Andrew Morton <akpm@osdl.org>]

Jens Axboe <axboe@suse.de> wrote:
>
> does zonelist->zones change further down the path
> and we need the revalidation before after restarting?
> 

err, yeah.   Like this, I think?



We modify local variable `z' while walking across the zones.  So we need to
restore it if we do the `goto restart' thing in the rare case where the
oom-killer was called.


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

 mm/page_alloc.c |    9 ++++-----
 1 files changed, 4 insertions(+), 5 deletions(-)

diff -puN mm/page_alloc.c~alloc_pages-oops-fix mm/page_alloc.c
--- 25/mm/page_alloc.c~alloc_pages-oops-fix	Thu Nov 17 12:58:38 2005
+++ 25-akpm/mm/page_alloc.c	Thu Nov 17 12:59:19 2005
@@ -845,13 +845,12 @@ __alloc_pages(gfp_t gfp_mask, unsigned i
 
 	might_sleep_if(wait);
 
-	z = zonelist->zones;  /* the list of zones suitable for gfp_mask */
+restart:
+	z = zonelist->zones;	  /* the list of zones suitable for gfp_mask */
 
-	if (unlikely(*z == NULL)) {
-		/* Should this ever happen?? */
+	if (unlikely(*z == NULL)) /* Should this ever happen?? */
 		return NULL;
-	}
-restart:
+
 	page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, order,
 				zonelist, ALLOC_CPUSET);
 	if (page)
_