Commit:     1105b5d1d44e6f00e31422dfcb0139bc8ae966a9
Parent:     8315f5d80a90247bf92232f92ca49933ac49327b
Author:     Jarek Poplawski <[EMAIL PROTECTED]>
AuthorDate: Mon Feb 11 21:24:56 2008 -0800
Committer:  David S. Miller <[EMAIL PROTECTED]>
CommitDate: Tue Feb 12 17:53:31 2008 -0800

    [AX25] af_ax25: remove sock lock in ax25_info_show()
    This lockdep warning:
    > =======================================================
    > [ INFO: possible circular locking dependency detected ]
    > 2.6.24 #3
    > -------------------------------------------------------
    > swapper/0 is trying to acquire lock:
    >  (ax25_list_lock){-+..}, at: [<f91dd3b1>] ax25_destroy_socket+0x171/0x1f0 
    > but task is already holding lock:
    >  (slock-AF_AX25){-+..}, at: [<f91dbabc>] 
ax25_std_heartbeat_expiry+0x1c/0xe0 [ax25]
    > which lock already depends on the new lock.
    shows that ax25_list_lock and slock-AF_AX25 are taken in different
    order: ax25_info_show() takes slock (bh_lock_sock(ax25->sk)) while
    ax25_list_lock is held, so reversely to other functions. To fix this
    the sock lock should be moved to ax25_info_start(), and there would
    be still problem with breaking ax25_list_lock (it seems this "proper"
    order isn't optimal yet). But, since it's only for reading proc info
    it seems this is not necessary (e.g.  ax25_send_to_raw() does similar
    reading without this lock too).
    So, this patch removes sock lock to avoid deadlock possibility; there
    is also used sock_i_ino() function, which reads sk_socket under proper
    read lock. Additionally printf format of this i_ino is changed to %lu.
    Reported-by: Bernard Pidoux F6BVP <[EMAIL PROTECTED]>
    Signed-off-by: Jarek Poplawski <[EMAIL PROTECTED]>
    Signed-off-by: David S. Miller <[EMAIL PROTECTED]>
 net/ax25/af_ax25.c |    6 ++----
 1 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c
index 8fc64e3..5a4337a 100644
--- a/net/ax25/af_ax25.c
+++ b/net/ax25/af_ax25.c
@@ -1928,12 +1928,10 @@ static int ax25_info_show(struct seq_file *seq, void *v)
        if (ax25->sk != NULL) {
-               bh_lock_sock(ax25->sk);
-               seq_printf(seq," %d %d %ld\n",
+               seq_printf(seq, " %d %d %lu\n",
-                          ax25->sk->sk_socket != NULL ? 
SOCK_INODE(ax25->sk->sk_socket)->i_ino : 0L);
-               bh_unlock_sock(ax25->sk);
+                          sock_i_ino(ax25->sk));
        } else {
                seq_puts(seq, " * * *\n");
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