Messages in this thread | | | Date | Wed, 23 Oct 2019 14:13:01 +0100 | From | Mel Gorman <> | Subject | Re: [RFC PATCH 1/2] mm, vmstat: hide /proc/pagetypeinfo from normal users |
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On Wed, Oct 23, 2019 at 12:27:36PM +0200, Michal Hocko wrote: > From: Michal Hocko <mhocko@suse.com> > > /proc/pagetypeinfo is a debugging tool to examine internal page > allocator state wrt to fragmentation. It is not very useful for > any other use so normal users really do not need to read this file. > > Waiman Long has noticed that reading this file can have negative side > effects because zone->lock is necessary for gathering data and that > a) interferes with the page allocator and its users and b) can lead to > hard lockups on large machines which have very long free_list. > > Reduce both issues by simply not exporting the file to regular users. > > Reported-by: Waiman Long <longman@redhat.com> > Cc: stable > Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mel Gorman <mgorman@suse.de>
-- Mel Gorman SUSE Labs
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