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SubjectRe: [PATCH] mm: avoid livelock on !__GFP_FS allocations
On Tue, 25 Oct 2011, Colin Cross wrote:

> GFP_KERNEL is __GFP_WAIT | __GFP_IO | __GFP_FS. Once driver suspend
> has started, gfp_allowed_mask is ~(__GFP_IO | GFP_FS), so any call to
> __alloc_pages_nodemask(GFP_KERNEL, ...) gets masked to effectively
> __alloc_pages_nodemask(__GFP_WAIT, ...).

Just passing __GFP_WAIT is the problem that you're trying to address,
though. Why not include __GFP_NORETRY since you know the liklihood of
allocation being successful on the second iteration is very slim since
you're not in a context where you can force reclaim or oom killing?

> The loop is in __alloc_pages_slowpath, from the rebalance label to
> should_alloc_retry.

The loop is by design and is activated because you're just passing
__GFP_WAIT in this context for no sensible reason.

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