linux-kernel - [PATCH 0/2] fix emergency unfreezing

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Date:   Tue,  3 Oct 2017 18:17:39 +0200
From:   Mateusz Guzik <mguzik@...hat.com>
To:     Eric Sandeen <sandeen@...hat.com>,
        Al Viro <viro@...iv.linux.org.uk>
Cc:     mszeredi@...hat.com, linux-fsdevel@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH 0/2] fix emergency unfreezing

Filesystems frozen with fsfreeze --freeze are not getting thawed with
sysrq j (or echo j > /proc/sysrq-trigger). Thawing only deals with bdev
part, does not do anything about fsfreeze.

I went for the easiest fix possible: just thaw the super block.
Doing it requires a little bit of refactoring in order to keep the sb
locked the whole time.

The first patch moves sb iteration found in emergency remount to a
dedicated func for code reuse. This patch patch is a no-op.

The second employs factored out code to do both bdev and sb thaws.

Mateusz Guzik (2):
  vfs: factor sb iteration out of do_emergency_remount
  buffer.c: call thaw_super during emergency thaw

 fs/buffer.c        |  25 +------------
 fs/super.c         | 105 +++++++++++++++++++++++++++++++++++++++--------------
 include/linux/fs.h |   1 +
 3 files changed, 80 insertions(+), 51 deletions(-)

-- 
1.8.3.1