proc: always do ->release

Current two-stage scheme of removing PDE emphasizes one bug in proc:

		open
				rmmod
				remove_proc_entry
		close

->release won't be called because ->proc_fops were cleared.  In simple
cases it's small memory leak.

For every ->open, ->release has to be done.  List of openers is introduced
which is traversed at remove_proc_entry() if neeeded.

Discussions with Al long ago (sigh).

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Alexey Dobriyan
2008-07-25 01:48:29 -07:00
committed by Linus Torvalds
parent 6e644c3126
commit 881adb8535
4 changed files with 92 additions and 4 deletions

View File

@@ -79,6 +79,7 @@ struct proc_dir_entry {
int pde_users; /* number of callers into module in progress */
spinlock_t pde_unload_lock; /* proc_fops checks and pde_users bumps */
struct completion *pde_unload_completion;
struct list_head pde_openers; /* who did ->open, but not ->release */
};
struct kcore_list {