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Subject: Re: [PATCH 0/2] "big hammer" for DAX msync/fsync correctness
To: Dan Williams <dan.j.williams@intel.com>,
        Thomas Gleixner <tglx@linutronix.de>
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Cc: Ross Zwisler <ross.zwisler@linux.intel.com>,
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From: "H. Peter Anvin" <hpa@zytor.com>
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Date: Fri, 6 Nov 2015 16:51:59 -0800
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On 11/06/15 15:17, Dan Williams wrote:
>>
>> Is it really required to do that on all cpus?
> 
> I believe it is, but I'll double check.
> 

It's required on all CPUs on which the DAX memory may have been dirtied.
 This is similar to the way we flush TLBs.

	-hpa