Re: [PATCH] mm, numa: Fix bad pmd by atomically check for pmd_trans_huge when marking page tables prot_numa

[Rik van Riel]

On Mon, 2017-04-10 at 10:48 +0100, Mel Gorman wrote:
> 
> While this could be fixed with heavy locking, it's only necessary to
> make a copy of the PMD on the stack during change_pmd_range and avoid
> races. A new helper is created for this as the check if quite subtle
> and the
> existing similar helpful is not suitable. This passed 154 hours of
> testing
> (usually triggers between 20 minutes and 24 hours) without detecting
> bad
> PMDs or corruption. A basic test of an autonuma-intensive workload
> showed
> no significant change in behaviour.
> 
> Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx

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