[PATCH] fs: add a sanity check in d_free

[Arjan van de Ven <arjan@infradead.org>]

Hi Al,

remember that debug session we did at KS? You suggested this patch back
then....


>From 7751eaf30474b8cbfaea64795805a17eab05ac53 Mon Sep 17 00:00:00 2001
From: Arjan van de Ven <arjan@linux.intel.com>
Date: Tue, 16 Sep 2008 16:51:17 -0700
Subject: [PATCH] fs: add a sanity check in d_free

we're seeing some corruption in the dentry->d_alias list that
appears like a free of an entry still on the list; this patch
adds a WARN_ON() to catch this scenario, as suggested by Al Viro

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
---
 fs/dcache.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/fs/dcache.c b/fs/dcache.c
index 80e9395..4c39a59 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -69,6 +69,7 @@ struct dentry_stat_t dentry_stat = {
 
 static void __d_free(struct dentry *dentry)
 {
+	WARN_ON(!list_empty(&dentry->d_alias));
 	if (dname_external(dentry))
 		kfree(dentry->d_name.name);
 	kmem_cache_free(dentry_cache, dentry); 
-- 
1.5.5.1



-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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