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

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, Apr 10, 2017 at 11:45:08AM -0500, Zi Yan 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
> 
> Does this patch fix the same problem fixed by Kirill's patch here?
> https://lkml.org/lkml/2017/3/2/347
> 

I don't think so. The race I'm concerned with is due to locks not being
held and is in a different path.

-- 
Mel Gorman
SUSE Labs

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>



[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Bugtraq]     [Linux OMAP]     [Linux MIPS]     [eCos]     [Asterisk Internet PBX]     [Linux API]
  Powered by Linux