[PATCH] suspend regression: sysfs deadlock

Suspend deadlocks when trying to unregister /sys/block/sr0.

This comes from Oliver's commit 94bebf4d1b
"Driver core: fix race in sysfs between sysfs_remove_file() and
read()/write()".

sysfs_write_file downs buffer->sem while calling flush_write_buffer, and
flushing that particular write buffer entails downing buffer->sem in
orphan_all_buffers, resulting in the obvious self-deadlock.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Hugh Dickins 2007-03-06 19:20:11 +00:00 committed by Linus Torvalds
parent 7c368bb104
commit 266d4f4037

View File

@ -227,11 +227,8 @@ static inline void orphan_all_buffers(struct inode *node)
mutex_lock_nested(&node->i_mutex, I_MUTEX_CHILD);
if (node->i_private) {
list_for_each_entry(buf, &set->associates, associates) {
down(&buf->sem);
list_for_each_entry(buf, &set->associates, associates)
buf->orphaned = 1;
up(&buf->sem);
}
}
mutex_unlock(&node->i_mutex);
}