init: Initialize noop_backing_dev_info early

noop_backing_dev_info is used by superblocks of various
pseudofilesystems such as kdevtmpfs. After commit 10e1407310
("writeback: Fix inode->i_io_list not be protected by inode->i_lock
error") this broke because __mark_inode_dirty() started to access more
fields from noop_backing_dev_info and this led to crashes inside
locked_inode_to_wb_and_lock_list() called from __mark_inode_dirty().
Fix the problem by initializing noop_backing_dev_info before the
filesystems get mounted.

Fixes: 10e1407310 ("writeback: Fix inode->i_io_list not be protected by inode->i_lock error")
Reported-and-tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reported-and-tested-by: Alexandru Elisei <alexandru.elisei@arm.com>
Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Jan Kara
2022-06-15 15:22:29 +02:00
parent 27cfa25895
commit 4bca7e80b6
3 changed files with 6 additions and 9 deletions

View File

@@ -119,6 +119,8 @@ int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio);
extern struct backing_dev_info noop_backing_dev_info;
int bdi_init(struct backing_dev_info *bdi);
/**
* writeback_in_progress - determine whether there is writeback in progress
* @wb: bdi_writeback of interest