Re: [patch v3] mm, hugetlb: abort __get_user_pages if current has been oom killed

From: Rik van Riel
Date: Mon Mar 09 2015 - 16:53:49 EST


On 03/09/2015 04:07 PM, 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
potentially deplete 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: Greg Thelen <gthelen@xxxxxxxxxx>
Cc: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
Cc: Davidlohr Bueso <dave@xxxxxxxxxxxx>
Acked-by: "Kirill A. Shutemov" <kirill@xxxxxxxxxxxxx>
Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx>

Acked-by: Rik van Riel <riel@xxxxxxxxxx>

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