From 807612db2f9940b9fa6deaef054eb16d51bd3e00 Mon Sep 17 00:00:00 2001 From: Andrew Ruder Date: Thu, 30 Jan 2014 09:26:54 -0600 Subject: [PATCH] fs/super.c: sync ro remount after blocking writers Move sync_filesystem() after sb_prepare_remount_readonly(). If writers sneak in anywhere from sync_filesystem() to sb_prepare_remount_readonly() it can cause inodes to be dirtied and writeback to occur well after sys_mount() has completely successfully. This was spotted by corrupted ubifs filesystems on reboot, but appears that it can cause issues with any filesystem using writeback. Cc: Artem Bityutskiy Cc: Christoph Hellwig Cc: Alexander Viro CC: Richard Weinberger Co-authored-by: Richard Weinberger Signed-off-by: Andrew Ruder Signed-off-by: Al Viro --- fs/super.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/super.c b/fs/super.c index cecd780e0f44..80d5cf2ca765 100644 --- a/fs/super.c +++ b/fs/super.c @@ -703,7 +703,6 @@ int do_remount_sb(struct super_block *sb, int flags, void *data, int force) if (flags & MS_RDONLY) acct_auto_close(sb); shrink_dcache_sb(sb); - sync_filesystem(sb); remount_ro = (flags & MS_RDONLY) && !(sb->s_flags & MS_RDONLY); @@ -720,6 +719,8 @@ int do_remount_sb(struct super_block *sb, int flags, void *data, int force) } } + sync_filesystem(sb); + if (sb->s_op->remount_fs) { retval = sb->s_op->remount_fs(sb, &flags, data); if (retval) { -- 2.20.1