Commit 266d4f40 authored Mar 06, 2007 by Hugh Dickins Committed by Linus Torvalds Mar 06, 2007

[PATCH] suspend regression: sysfs deadlock



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

This comes from Oliver's commit 94bebf4d
"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>

parent 7c368bb1

fs/sysfs/inode.c

+1 −4

Original line number	Diff line number	Diff line
		@@ -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);
		}