[Devel] [PATCH -mm] proc: remove pathetic ->deleted WARN_ON

Alexey Dobriyan adobriyan at sw.ru
Tue Mar 13 07:31:06 PDT 2007


WARN_ON(de && de->deleted); is sooo unreliable. Why?

proc_lookup				remove_proc_entry
===========				=================
lock_kernel();
spin_lock(&proc_subdir_lock);
[find proc entry]
spin_unlock(&proc_subdir_lock);
					spin_lock(&proc_subdir_lock);
					[find proc entry]

proc_get_inode
==============
WARN_ON(de && de->deleted);			...

					if (!atomic_read(&de->count))
						free_proc_entry(de);
					else
						de->deleted = 1;

So, if you have some strange oops [1], and doesn't see this WARN_ON it means
nothing.

[1] try_module_get() of module which doesn't exist, two lines below
    should suffice, or not?

Signed-off-by: Alexey Dobriyan <adobriyan at sw.ru>
---

 fs/proc/inode.c |    2 --
 1 file changed, 2 deletions(-)

--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -418,8 +418,6 @@ struct inode *proc_get_inode(struct supe
 {
 	struct inode * inode;
 
-	WARN_ON(de && de->deleted);
-
 	if (de != NULL && !try_module_get(de->owner))
 		goto out_mod;
 




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