From: Jia-Ju Bai <baijiaju1990@163.com>
To: trond.myklebust@primarydata.com, anna.schumaker@netapp.com
Cc: linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org,
Jia-Ju Bai <baijiaju1990@163.com>
Subject: [PATCH] fs: nfs: Fix a sleep-in-atomic bug in nfs_access_add_cache
Date: Mon, 5 Jun 2017 16:05:04 +0800 [thread overview]
Message-ID: <1496649904-1855-1-git-send-email-baijiaju1990@163.com> (raw)
The driver may sleep under a rcu read lock, and function call path is:
nfs_permission (acquire the lock by rcu_read_lock)
nfs_do_access
nfs_access_add_cache
kmalloc(GFP_KERNEL) --> may sleep
To fix it, "GFP_KERNEL" is replaced with "GFP_ATOMIC".
Signed-off-by: Jia-Ju Bai <baijiaju1990@163.com>
---
fs/nfs/dir.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 32ccd77..7a074db 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -2333,7 +2333,7 @@ static void nfs_access_add_rbtree(struct inode *inode, struct nfs_access_entry *
void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set)
{
- struct nfs_access_entry *cache = kmalloc(sizeof(*cache), GFP_KERNEL);
+ struct nfs_access_entry *cache = kmalloc(sizeof(*cache), GFP_ATOMIC);
if (cache == NULL)
return;
RB_CLEAR_NODE(&cache->rb_node);
--
1.7.9.5
next reply other threads:[~2017-06-05 8:02 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-06-05 8:05 Jia-Ju Bai [this message]
2017-06-05 11:48 ` [PATCH] fs: nfs: Fix a sleep-in-atomic bug in nfs_access_add_cache Trond Myklebust
2017-06-05 11:48 ` Trond Myklebust
2017-06-05 12:36 ` Jia-Ju Bai
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