diff mbox series

[08/19] pstore: shrink the pstore_sb_lock critical section in pstore_kill_sb

Message ID 20230913111013.77623-9-hch@lst.de (mailing list archive)
State Handled Elsewhere
Headers show
Series [01/19] fs: reflow deactivate_locked_super | expand

Commit Message

Christoph Hellwig Sept. 13, 2023, 11:10 a.m. UTC
->kill_sb can't race with creating ->fill_super because pstore is a
_single file system that only ever has a single sb instance, and we wait
for the previous one to go away before creating a new one.  Reduce
the critical section so that is is not held over generic_shutdown_super.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/pstore/inode.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

Comments

Kees Cook Sept. 13, 2023, 10:07 p.m. UTC | #1
On Wed, Sep 13, 2023 at 08:10:02AM -0300, Christoph Hellwig wrote:
> ->kill_sb can't race with creating ->fill_super because pstore is a
> _single file system that only ever has a single sb instance, and we wait
> for the previous one to go away before creating a new one.  Reduce
> the critical section so that is is not held over generic_shutdown_super.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Thanks for the refactoring!

Reviewed-by: Kees Cook <keescook@chromium.org>
diff mbox series

Patch

diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index 585360706b335f..fd1d24b47160d0 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -467,10 +467,9 @@  static struct dentry *pstore_mount(struct file_system_type *fs_type,
 
 static void pstore_kill_sb(struct super_block *sb)
 {
-	mutex_lock(&pstore_sb_lock);
-	WARN_ON(pstore_sb && pstore_sb != sb);
-
 	kill_litter_super(sb);
+
+	mutex_lock(&pstore_sb_lock);
 	pstore_sb = NULL;
 
 	mutex_lock(&records_list_lock);