Re: [PATCH 5/6] mempolicy: fix a memory corruption by refcount imbalance in alloc_pages_vma()

KOSAKI Motohiro
2012-06-12T16:31:52Z

> Why does dequeue_huge_page_vma() not need to be changed as well? It's
> currently using mpol_cond_put() but if there is a goto retry_cpuset then
> will it have not take an additional reference count and leak?

dequeue_huge_page_vma() also uses get_vma_policy() and mpol_cond_put()
pair. thus we don't need special concern.

> Would it be more straight forward to put the mpol_cond_put() and __mpol_put()
> calls after the "goto retry_cpuset" checks instead?

I hope to keep symmetric. Sane design prevent a lot of unintentional breakage.
Frankly says, now all caller assume the symmetric. It's natural.