Re: [patch v2] mm, hugetlb: abort __get_user_pages if current has been oom killed

Kirill A. Shutemov
2015-03-09T11:24:49Z

On Mon, Mar 09, 2015 at 12:42:15AM -0700, David Rientjes wrote:
> If __get_user_pages() is faulting a significant number of hugetlb pages,
> usually as the result of mmap(MAP_LOCKED), it can potentially allocate a
> very large amount of memory.
>
> If the process has been oom killed, this will cause a lot of memory to
> be overcharged to its memcg since it has access to memory reserves or
> could potentially deplete all system memory reserves.
>
> In the same way that commit 4779280d1ea4 ("mm: make get_user_pages()
> interruptible") aborted for pending SIGKILLs when faulting non-hugetlb
> memory, based on the premise of commit 462e00cc7151 ("oom: stop
> allocating user memory if TIF_MEMDIE is set"), hugetlb page faults now
> terminate when the process has been oom killed.
>
> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
> Cc: Davidlohr Bueso <dave@stgolabs.net>
> Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
> Signed-off-by: David Rientjes <rientjes@google.com>

Acked-by: Kirill A. Shutemo <kirill.shutemov@linux.intel.com>

--
Kirill A. Shutemov