Messages in this thread | | | Subject | Re: 2.6.21-rc5-mm4 (SLUB) | From | Badari Pulavarty <> | Date | Wed, 04 Apr 2007 15:53:04 -0700 |
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On Wed, 2007-04-04 at 11:22 -0700, Christoph Lameter wrote: > On Wed, 4 Apr 2007, Christoph Lameter wrote: > > > Yes. slub_debug=U. But user tracking may need to increase the slab > > size (depends on the padding available in the slab) to store the > > tracking information, so you may not get the same corruption. > > Hummm U is switching off merging and you may need merging to trigger the > discovery of the overwrite. > > Here is a patch to enable merging even while tracking slabs. This patch > should not be applied to mm. In general tracking requires knowing which > slab the objects come from and merging looses that information. > > Index: linux-2.6.21-rc5-mm4/mm/slub.c > =================================================================== > --- linux-2.6.21-rc5-mm4.orig/mm/slub.c 2007-04-04 11:19:29.000000000 -0700 > +++ linux-2.6.21-rc5-mm4/mm/slub.c 2007-04-04 11:19:35.000000000 -0700 > @@ -86,7 +86,7 @@ > /* > * Set of flags that will prevent slab merging > */ > -#define SLUB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ > +#define SLUB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | \ > SLAB_TRACE | SLAB_DESTROY_BY_RCU) > > #define SLUB_MERGE_SAME (SLAB_DEBUG_FREE | SLAB_RECLAIM_ACCOUNT | \ >
Here is the slub_debug=FU output with the above patch.
Thanks, Badari
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