Messages in this thread | | | Date | Wed, 2 Apr 2008 03:55:39 -0700 | From | "Paul E. McKenney" <> | Subject | Re: kmemcheck caught read from freed memory (cfq_free_io_context) |
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On Wed, Apr 02, 2008 at 09:28:46AM +0200, Ingo Molnar wrote: > > * Jens Axboe <jens.axboe@oracle.com> wrote: > > > On Wed, Apr 02 2008, Pekka J Enberg wrote: > > > On Wed, 2 Apr 2008, Jens Axboe wrote: > > > > Good catch, I wonder why it didn't complain in my testing. I've added a > > > > patch to fix that, please see it here: > > > > > > You probably don't have kmemcheck in your kernel ;-) > > > > Ehm no, you are right :) > > ... and you can get kmemcheck by testing on x86.git/latest: > > http://people.redhat.com/mingo/x86.git/README > > ;-)
I will check this when I get back to some bandwidth -- but in the meantime, does kmemcheck special-case SLAB_DESTROY_BY_RCU? It is legal to access newly-freed items in that case, as long as you did rcu_read_lock() before gaining a reference to them and don't hold the reference past the matching rcu_read_unlock().
Thanx, Paul
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