From: axboe@kernel.dk (Jens Axboe)
Subject: [PATCHv3 for-4.7] nvme: Remove RCU namespace protection
Date: Tue, 12 Jul 2016 16:15:13 -0700 [thread overview]
Message-ID: <57857A01.1080004@kernel.dk> (raw)
In-Reply-To: <20160709010754.GA28997@localhost.localdomain>
On 07/08/2016 06:07 PM, Keith Busch wrote:
> On Wed, Jul 06, 2016@11:22:50AM -0600, Keith Busch wrote:
>> We can't block with RCU read lock held, but we need to do potentially
>> blocking stuff to namespace queues when iterating the list. This patch
>> removes the rcu read locking.
>>
>> Any list iteration that does IO has to be done unlocked to allow recovery.
>> The caller must ensure the list can not be manipulated under such
>> conditions. List iterations that do not issue IO can safely use the lock
>> since it wouldn't block recovery from missing IO completions.
>
> Ping? Would hate to release a kernel with obvious bugs.
I'm going back and forth on this... This isn't a regression for 4.7, is
it? If so, I'd be a lot more comfortable queuing this up for 4.8 (marked
stable) instead. It'll be another late addition, causing issues when it
comes time to merge for-4.8/drivers in the next merge window.
--
Jens Axboe
next prev parent reply other threads:[~2016-07-12 23:15 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-06 17:22 [PATCHv3 for-4.7] nvme: Remove RCU namespace protection Keith Busch
2016-07-09 1:07 ` Keith Busch
2016-07-10 9:47 ` Christoph Hellwig
2016-07-11 14:25 ` Keith Busch
2016-07-12 23:15 ` Jens Axboe [this message]
2016-07-13 2:22 ` Christoph Hellwig
2016-07-13 16:24 ` Jens Axboe
2016-07-13 16:48 ` Keith Busch
2016-07-13 16:41 ` Jens Axboe
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=57857A01.1080004@kernel.dk \
--to=axboe@kernel.dk \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.