From: "Theodore Y. Ts'o" <tytso@mit.edu>
To: Jon Derrick <jonathan.derrick@intel.com>
Cc: linux-ext4@vger.kernel.org,
Andreas Dilger <adilger.kernel@dilger.ca>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ext4: Check superblock mapped prior to committing
Date: Mon, 2 Jul 2018 18:50:42 -0400 [thread overview]
Message-ID: <20180702225042.GF30481@thunk.org> (raw)
In-Reply-To: <1530300995-25583-1-git-send-email-jonathan.derrick@intel.com>
On Fri, Jun 29, 2018 at 01:36:35PM -0600, Jon Derrick wrote:
> This patch attempts to close a hole leading to a BUG seen with hot
> removals during writes [1].
>
> A block device (NVME namespace in this test case) is formatted to EXT4
> without partitions. It's mounted and write I/O is run to a file, then
> the device is hot removed from the slot. The superblock attempts to be
> written to the drive which is no longer present.
>
> The typical chain of events leading to the BUG:
> ext4_commit_super()
> __sync_dirty_buffer()
> submit_bh()
> submit_bh_wbc()
> BUG_ON(!buffer_mapped(bh));
>
> This fix checks for the superblock's buffer head being mapped prior to
> syncing.
>
> [1] https://www.spinics.net/lists/linux-ext4/msg56527.html
>
> Signed-off-by: Jon Derrick <jonathan.derrick@intel.com>
Thanks, applied.
- Ted
prev parent reply other threads:[~2018-07-02 22:50 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-06-29 19:36 [PATCH] ext4: Check superblock mapped prior to committing Jon Derrick
2018-06-30 4:36 ` Andreas Dilger
2018-07-02 22:50 ` Theodore Y. Ts'o [this message]
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=20180702225042.GF30481@thunk.org \
--to=tytso@mit.edu \
--cc=adilger.kernel@dilger.ca \
--cc=jonathan.derrick@intel.com \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).