From: Christoph Hellwig <hch@lst.de>
To: Mike Snitzer <snitzer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
dm-devel@redhat.com, linux-block@vger.kernel.org
Subject: Re: [PATCH 4/8] block: support delayed holder registration
Date: Wed, 28 Jul 2021 08:54:03 +0200 [thread overview]
Message-ID: <20210728065403.GA4815@lst.de> (raw)
In-Reply-To: <YQAu7KKyKnCm+tlf@redhat.com>
On Tue, Jul 27, 2021 at 12:06:04PM -0400, Mike Snitzer wrote:
> This header starts to shine some light on what is motivating this
> series by touching on "all kinds of bad side effects" being fixed.
> Any chance you could elaborate what you've noticed/found/hit?
The proble mis that it leaves the queue in a weird half state. The
normal states for a gendisk are:
1) allocated (after *alloc_disk)
2) registered (after add_disk*)
3) unregistered (after del_gendisk)
the delayed queue registration adds a weird half state where it is
sort of registered, except for in sysfs and the elevator. I have
some pretty big changes between how the disk and queue interact
that tripped over it, but even right now code has to be very careful
in the takedown path to deal with the half-initialized disks.
WARNING: multiple messages have this Message-ID (diff)
From: Christoph Hellwig <hch@lst.de>
To: Mike Snitzer <snitzer@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>,
linux-block@vger.kernel.org, dm-devel@redhat.com,
Christoph Hellwig <hch@lst.de>
Subject: Re: [dm-devel] [PATCH 4/8] block: support delayed holder registration
Date: Wed, 28 Jul 2021 08:54:03 +0200 [thread overview]
Message-ID: <20210728065403.GA4815@lst.de> (raw)
In-Reply-To: <YQAu7KKyKnCm+tlf@redhat.com>
On Tue, Jul 27, 2021 at 12:06:04PM -0400, Mike Snitzer wrote:
> This header starts to shine some light on what is motivating this
> series by touching on "all kinds of bad side effects" being fixed.
> Any chance you could elaborate what you've noticed/found/hit?
The proble mis that it leaves the queue in a weird half state. The
normal states for a gendisk are:
1) allocated (after *alloc_disk)
2) registered (after add_disk*)
3) unregistered (after del_gendisk)
the delayed queue registration adds a weird half state where it is
sort of registered, except for in sysfs and the elevator. I have
some pretty big changes between how the disk and queue interact
that tripped over it, but even right now code has to be very careful
in the takedown path to deal with the half-initialized disks.
--
dm-devel mailing list
dm-devel@redhat.com
https://listman.redhat.com/mailman/listinfo/dm-devel
next prev parent reply other threads:[~2021-07-28 6:54 UTC|newest]
Thread overview: 60+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-25 5:54 use regular gendisk registration in device mapper Christoph Hellwig
2021-07-25 5:54 ` [dm-devel] " Christoph Hellwig
2021-07-25 5:54 ` [PATCH 1/8] block: make the block holder code optional Christoph Hellwig
2021-07-25 5:54 ` [dm-devel] " Christoph Hellwig
2021-07-29 16:25 ` Mike Snitzer
2021-07-29 16:25 ` [dm-devel] " Mike Snitzer
2021-07-25 5:54 ` [PATCH 2/8] block: remove the extra kobject reference in bd_link_disk_holder Christoph Hellwig
2021-07-25 5:54 ` [dm-devel] " Christoph Hellwig
2021-07-29 16:27 ` Mike Snitzer
2021-07-29 16:27 ` [dm-devel] " Mike Snitzer
2021-07-25 5:54 ` [PATCH 3/8] block: look up holders by bdev Christoph Hellwig
2021-07-25 5:54 ` [dm-devel] " Christoph Hellwig
2021-07-25 5:54 ` [PATCH 4/8] block: support delayed holder registration Christoph Hellwig
2021-07-25 5:54 ` [dm-devel] " Christoph Hellwig
2021-07-27 16:06 ` Mike Snitzer
2021-07-27 16:06 ` [dm-devel] " Mike Snitzer
2021-07-28 6:54 ` Christoph Hellwig [this message]
2021-07-28 6:54 ` Christoph Hellwig
2021-07-29 16:32 ` Mike Snitzer
2021-07-29 16:32 ` [dm-devel] " Mike Snitzer
2021-07-25 5:54 ` [PATCH 5/8] dm: cleanup cleanup_mapped_device Christoph Hellwig
2021-07-25 5:54 ` [dm-devel] " Christoph Hellwig
2021-07-29 16:33 ` Mike Snitzer
2021-07-29 16:33 ` [dm-devel] " Mike Snitzer
2021-07-25 5:54 ` [PATCH 6/8] dm: move setting md->type into dm_setup_md_queue Christoph Hellwig
2021-07-25 5:54 ` [dm-devel] " Christoph Hellwig
2021-07-29 16:34 ` Mike Snitzer
2021-07-29 16:34 ` [dm-devel] " Mike Snitzer
2021-07-25 5:54 ` [PATCH 7/8] dm: delay registering the gendisk Christoph Hellwig
2021-07-25 5:54 ` [dm-devel] " Christoph Hellwig
2021-07-29 16:36 ` Mike Snitzer
2021-07-29 16:36 ` [dm-devel] " Mike Snitzer
2021-07-25 5:54 ` [PATCH 8/8] block: remove support for delayed queue registrations Christoph Hellwig
2021-07-25 5:54 ` [dm-devel] " Christoph Hellwig
2021-07-29 16:37 ` Mike Snitzer
2021-07-29 16:37 ` [dm-devel] " Mike Snitzer
2021-07-27 15:58 ` use regular gendisk registration in device mapper Mike Snitzer
2021-07-27 15:58 ` [dm-devel] " Mike Snitzer
2021-07-27 16:02 ` Christoph Hellwig
2021-07-27 16:02 ` [dm-devel] " Christoph Hellwig
2021-07-27 16:18 ` Mike Snitzer
2021-07-27 16:18 ` [dm-devel] " Mike Snitzer
2021-07-27 20:38 ` Milan Broz
2021-07-27 20:38 ` Milan Broz
2021-07-28 7:06 ` Christoph Hellwig
2021-07-28 7:06 ` Christoph Hellwig
2021-07-28 8:37 ` Milan Broz
2021-07-28 8:37 ` Milan Broz
2021-07-28 11:24 ` Christoph Hellwig
2021-07-28 11:24 ` Christoph Hellwig
2021-07-29 15:01 ` Milan Broz
2021-07-29 15:01 ` Milan Broz
2021-07-28 16:17 ` Mike Snitzer
2021-07-28 16:17 ` [dm-devel] " Mike Snitzer
2021-07-29 7:50 ` Milan Broz
2021-07-29 7:50 ` [dm-devel] " Milan Broz
2021-07-27 22:52 ` Mike Snitzer
2021-07-27 22:52 ` [dm-devel] " Mike Snitzer
2021-08-04 9:41 use regular gendisk registration in device mapper v2 Christoph Hellwig
2021-08-04 9:41 ` [PATCH 4/8] block: support delayed holder registration Christoph Hellwig
[not found] ` <CGME20210810213058eucas1p109323e3c3ecaa76d37d8cf63b6d8ecfd@eucas1p1.samsung.com>
2021-08-10 21:30 ` Marek Szyprowski
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