Re: Block layer projects that I haven't had time for

From: Dongsu Park
Date: Thu Dec 11 2014 - 05:08:20 EST


Hi Ming & Kent,

On 10.12.2014 23:11, Ming Lin wrote:
> > On Wed, Dec 10, 2014 at 02:42:14PM -0800, Ming Lin wrote:
> > Try this fix:
> Yes, it fixed ext4 problem.

@kent: Thank you for the patch. Indeed it fixes the ext4 lockup I've seen.
I've applied it to my tree, under the branch block-mpage-bvecs-for-next.
See 0d2e05525a58 ("fs/ext4: fix a lockup when writing blocks into ext4
rootfs") <https://github.com/dongsupark/linux/commit/0d2e05525a58>.

After that of course, more bugs start to appear, e.g. crash with virtio-blk,
like we'd have opened a can of worms. ;-)

> Just tried to edit a btrfs file.
>
> [ 45.216351] BTRFS error (device sdb1): partial page write in btrfs with
> offset 0 and length 8192
> [ 45.217522] BTRFS critical (device sdb1): bad ordered accounting left 0
> size 4096

@ming: I guess you managed to see this error as you're testing with a
SCSI device, not virtio-blk device like me.
Are you seeing it without any back traces?
Does the attached patch fix your issue?
(This is already included in the branch block-mpage-bvecs-for-next.)

Thanks,
Dongsu

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