[PATCH] mm: fallback_alloc cpuset_zone_allowed irq fix

[PATCH] mm: fallback_alloc cpuset_zone_allowed irq fix

[Paul Jackson]

From: Paul Jackson <pj@sgi.com>

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>

---
 mm/slab.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletion(-)

--- 2.6.19-rc6-mm2.orig/mm/slab.c	2006-11-30 19:45:50.000000000 -0800
+++ 2.6.19-rc6-mm2/mm/slab.c	2006-12-05 22:41:49.000000000 -0800
@@ -3261,7 +3261,8 @@ void *fallback_alloc(struct kmem_cache *
 		int nid = zone_to_nid(*z);
 
 		if (zone_idx(*z) <= ZONE_NORMAL &&
-				cpuset_zone_allowed(*z, flags) &&
+				cpuset_zone_allowed(*z,
+					flags | __GFP_HARDWALL) &&
 				cache->nodelists[nid])
 			obj = ____cache_alloc_node(cache,
 					flags | __GFP_THISNODE, nid);

-- 
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