[PATCH] NVMe: Skip namespaces with interleaved meta-data

[Andrey Kuzmin]

On Wed, Jan 28, 2015 at 6:11 PM, Keith Busch <keith.busch at intel.com> wrote:
> On Tue, 27 Jan 2015, Martin K. Petersen wrote:
>>>>>>>
>>>>>>> "Keith" == Keith Busch <keith.busch at intel.com> writes:
>>
>> Keith,
>>
>> Keith> I can't register with the blk-integrity extentions until after
>> Keith> add_disk is completed because the disk's kobj needs to be
>> Keith> initialized before blk_integrity_register. The 'add_disk' itself
>> Keith> submits a lot of reads, though. Am I missing something, or how
>> Keith> could those succeed when the block device's required integrity
>> Keith> format hasn't been setup?
>>
>> Protection is optional and enabled on a per-I/O basis. Even if the block
>> layer's auto protection is enabled it is normal to see a flutter of
>> unprotected reads while partitions are being scanned.
>
>
> Thanks for the info. NVMe doesn't appear to allow disabling metadata
> per-io

PRACT gives you this opportunity on a command basis
(Read/Write/Compare), although I see Martin has already suggested this
workaround of setting PRACT to 1 (strip).

Regards,
Andrey


> except for a subset of formats. If that's correct, this driver
> would have to provide a valid protection buffer for all IO. Checking
> with committee comrades for clarification.
>
>
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