From: NeilBrown Date: Thu, 8 Feb 2007 22:20:30 +0000 (-0800) Subject: [PATCH] knfsd: fix a race in closing NFSd connections X-Git-Tag: v2.6.21-rc1~83^2~20 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=aaf68cfbf2241d24d46583423f6bff5c47e088b3;p=pandora-kernel.git [PATCH] knfsd: fix a race in closing NFSd connections If you lose this race, it can iput a socket inode twice and you get a BUG in fs/inode.c When I added the option for user-space to close a socket, I added some cruft to svc_delete_socket so that I could call that function when closing a socket per user-space request. This was the wrong thing to do. I should have just set SK_CLOSE and let normal mechanisms do the work. Not only wrong, but buggy. The locking is all wrong and it openned up a race where-by a socket could be closed twice. So this patch: Introduces svc_close_socket which sets SK_CLOSE then either leave the close up to a thread, or calls svc_delete_socket if it can get SK_BUSY. Adds a bias to sk_busy which is removed when SK_DEAD is set, This avoid races around shutting down the socket. Changes several 'spin_lock' to 'spin_lock_bh' where the _bh was missing. Bugzilla-url: http://bugzilla.kernel.org/show_bug.cgi?id=7916 Signed-off-by: Neil Brown Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Reading git-diff-tree failed