Messages in this thread | | | Date | Tue, 7 Apr 2009 22:24:49 +0200 | From | Andi Kleen <> | Subject | Re: [PATCH] [8/16] POISON: Add various poison checks in mm/memory.c |
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> I think we missed each other here. I wasn't talking about _why_ you > take that reference -- that is clear. But I see these two > possibilities: > > a) memory_failure() is called on a page on the free list, the > get_page() will trigger a bug because the refcount is 0
Ah got it now. Sorry for misreading you. That's indeed a problem. Fixing.
free pages was something my injector based test suite didn't cover :/
> b) if that is not possible, the above check is not needed
There was at least one case where the process could free it anyways. I think. Or maybe that was something I fixed in a different way. It's possible this check is not needed, but it's probably safer to keep it (and it's all super slow path)
-Andi
-- ak@linux.intel.com -- Speaking for myself only.
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