Linux-XFS Archive on lore.kernel.org
 help / color / Atom feed
From: "Darrick J. Wong" <darrick.wong@oracle.com>
To: darrick.wong@oracle.com
Cc: linux-xfs@vger.kernel.org, hch@infradead.org
Subject: [PATCH 0/2] xfs: fix stale disk exposure after crash
Date: Wed, 15 Jan 2020 22:15:44 -0800
Message-ID: <157915534429.2406747.2688273938645013888.stgit@magnolia> (raw)

Hi all,

These two patches try to shrink the window during which a crash during
writeback can expose stale disk contents.  The first patch causes
delalloc reservations to be converted to unwritten extents for any
writeback that's going on within EOF.

The second patch selectively relaxes the unwritten writeout requirement
when the entire file is being flushed (ala fsync) and ensures that
writeback of a range after the ondisk EOF is expanded downwards to the
old EOF to ensure that increasing a file's size doesn't leave us
vulnerable to exposure of stale disk contents from a previous
speculative allocation.

This solves the regressions in generic/536 and generic/042.

If you're going to start using this mess, you probably ought to just
pull from my git trees, which are linked below.

This has been lightly tested with fstests.  Enjoy!
Comments and questions are, as always, welcome.

--D

kernel git tree:
https://git.kernel.org/cgit/linux/kernel/git/djwong/xfs-linux.git/log/?h=stale-exposure

xfsprogs git tree:
https://git.kernel.org/cgit/linux/kernel/git/djwong/xfsprogs-dev.git/log/?h=stale-exposure

             reply index

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-01-16  6:15 Darrick J. Wong [this message]
2020-01-16  6:15 ` [PATCH 1/2] xfs: force writes to delalloc regions to unwritten Darrick J. Wong
2020-01-16 16:47   ` Christoph Hellwig
2020-01-16 23:16     ` Darrick J. Wong
2020-01-19 20:49   ` Dave Chinner
2020-02-03 20:14     ` Darrick J. Wong
2020-01-16  6:15 ` [PATCH 2/2] xfs: relax unwritten writeback overhead under some circumstances Darrick J. Wong
2020-01-16 16:49   ` Christoph Hellwig
2020-01-16 23:15     ` Darrick J. Wong
2020-01-16 16:49 ` [PATCH 0/2] xfs: fix stale disk exposure after crash Christoph Hellwig
2020-01-16 23:00   ` Darrick J. Wong

Reply instructions:

You may reply publically 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=157915534429.2406747.2688273938645013888.stgit@magnolia \
    --to=darrick.wong@oracle.com \
    --cc=hch@infradead.org \
    --cc=linux-xfs@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

Linux-XFS Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-xfs/0 linux-xfs/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-xfs linux-xfs/ https://lore.kernel.org/linux-xfs \
		linux-xfs@vger.kernel.org
	public-inbox-index linux-xfs

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-xfs


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git