From: Paul Jackson <pj@sgi.com>
Date: Fri, 8 Dec 2006 10:35:53 +0000 (-0800)
Subject: [PATCH] mm: fallback_alloc cpuset_zone_allowed irq fix
X-Git-Tag: v2.6.20-rc1~34^2~407
X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=b8b50b6519afa9891b753c4fffa89d89e04df66a;p=linux-2.6-omap-h63xx.git

[PATCH] mm: fallback_alloc cpuset_zone_allowed irq fix

fallback_alloc() could end up calling cpuset_zone_allowed() with interrupts
disabled (by code in kmem_cache_alloc_node()), but without __GFP_HARDWALL
set, leading to a possible call of a sleeping function with interrupts
disabled.

This results in the BUG report:

  BUG: sleeping function called from invalid context at kernel/cpuset.c:1520
in_atomic():0, irqs_disabled():1

Thanks to Paul Menage for catching this one.

Signed-off-by: Paul Jackson <pj@sgi.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/mm/slab.c b/mm/slab.c
index 068cb4503c1..e90b6100a92 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3182,7 +3182,7 @@ retry:
 	for (z = zonelist->zones; *z && !obj; z++) {
 		nid = zone_to_nid(*z);
 
-		if (cpuset_zone_allowed(*z, flags) &&
+		if (cpuset_zone_allowed(*z, flags | __GFP_HARDWALL) &&
 			cache->nodelists[nid] &&
 			cache->nodelists[nid]->free_objects)
 				obj = ____cache_alloc_node(cache,