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Re: [PATCH 1/1] workqueue: fix ghost PENDING flag while doing MQ IO

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Hello,

On Tue, Apr 26, 2016 at 01:15:35PM +0200, Roman Pen wrote:
...
> This behaviour can be explained by speculative LOAD of hctx->ctx_map on
> CPU#0, which is reordered with clear of PENDING bit and executed _before_
> actual STORE of bit 1 on CPU#1.
> 
> The proper fix is an explicit full barrier <mfence>, which guarantees
> that clear of PENDING bit is to be executed before all possible
> speculative LOADS or STORES inside actual work function.

Applied to workqueue/for-4.6-fixes.

Thanks.

-- 
tejun

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[PATCH 1/1] workqueue: fix ghost PENDING flag while doing MQ IO Roman Pen <roman.penyaev@profitbricks.com> - 2016-04-26 13:50 +0200
  Re: [PATCH 1/1] workqueue: fix ghost PENDING flag while doing MQ IO Tejun Heo <tj@kernel.org> - 2016-04-26 17:30 +0200
  Re: [PATCH 1/1] workqueue: fix ghost PENDING flag while doing MQ IO Peter Hurley <peter@hurleysoftware.com> - 2016-04-26 23:00 +0200

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