Messages in this thread Patch in this message | | | Date | Fri, 6 Jun 2014 09:46:57 -0500 (CDT) | From | Christoph Lameter <> | Subject | Re: [PATCH -mm v2 5/8] slub: make slab_free non-preemptable |
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On Fri, 6 Jun 2014, Vladimir Davydov wrote:
> This patch makes SLUB's implementation of kmem_cache_free > non-preemptable. As a result, synchronize_sched() will work as a barrier > against kmem_cache_free's in flight, so that issuing it before cache > destruction will protect us against the use-after-free.
Subject: slub: reenable preemption before the freeing of slabs from slab_free
I would prefer to call the page allocator with preemption enabled if possible.
Signed-off-by: Christoph Lameter <cl@linux.com>
Index: linux/mm/slub.c =================================================================== --- linux.orig/mm/slub.c 2014-05-29 11:45:32.065859887 -0500 +++ linux/mm/slub.c 2014-06-06 09:45:12.822480834 -0500 @@ -1998,6 +1998,7 @@ if (n) spin_unlock(&n->list_lock);
+ preempt_enable(); while (discard_page) { page = discard_page; discard_page = discard_page->next; @@ -2006,6 +2007,7 @@ discard_slab(s, page); stat(s, FREE_SLAB); } + preempt_disable(); #endif }
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