From 90c5029e471636f21221bf66b9a46ada2ab79a22 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 27 Jul 2005 11:43:50 -0700 Subject: [PATCH] [PATCH] Undo mempolicy shared policy rbtree microoptimization All mempolicy changes must be inside the spinlock and readding the rb_erase prevents a crash while doing: > echo "1" > /tmp/numatest > numactl --length=0x4000 --shm /tmp/numatest --localalloc > numactl --length=0x2000 --offset=0 --shm /tmp/numatest --membind=0 > numactl --length=0x2000 --offset=0x2000 --shm /tmp/numatest --membind=1 > ipcs > ipcrm -M "the_key_value_of_this_shm_area" Based on a patch by John Blackwood Cc: Cc: Signed-off-by: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/mempolicy.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index cb41c31e7c87..1694845526be 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -1138,11 +1138,11 @@ void mpol_free_shared_policy(struct shared_policy *p) while (next) { n = rb_entry(next, struct sp_node, nd); next = rb_next(&n->nd); + rb_erase(&n->nd, &p->root); mpol_free(n->policy); kmem_cache_free(sn_cache, n); } spin_unlock(&p->lock); - p->root = RB_ROOT; } /* assumes fs == KERNEL_DS */