Re: [syzbot] Re: [syzbot] [fs?] possible deadlock in __simple_recursive_removal

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Subject: Re: [syzbot] [fs?] possible deadlock in __simple_recursive_removal
Author: lizhi.xu@windriver.com

#syz test

diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index 0bd1df2ebb47..e30270e5883a 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -175,7 +175,7 @@ rpc_close_pipes(struct dentry *dentry)
 	int need_release;
 	LIST_HEAD(free_list);
 
-	inode_lock(inode);
+	inode_lock_nested(inode, I_MUTEX_CHILD);
 	spin_lock(&pipe->lock);
 	need_release = pipe->nreaders != 0 || pipe->nwriters != 0;
 	pipe->nreaders = 0;