3.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet <edumazet@xxxxxxxxxx> [ Upstream commit 9979a55a833883242e3a29f3596676edd7199c46 ] The WARN_ON(in_interrupt()) in net_enable_timestamp() can get false positive, in socket clone path, run from softirq context : [ 3641.624425] WARNING: at net/core/dev.c:1532 net_enable_timestamp+0x7b/0x80() [ 3641.668811] Call Trace: [ 3641.671254] <IRQ> [<ffffffff80286817>] warn_slowpath_common+0x87/0xc0 [ 3641.677871] [<ffffffff8028686a>] warn_slowpath_null+0x1a/0x20 [ 3641.683683] [<ffffffff80742f8b>] net_enable_timestamp+0x7b/0x80 [ 3641.689668] [<ffffffff80732ce5>] sk_clone_lock+0x425/0x450 [ 3641.695222] [<ffffffff8078db36>] inet_csk_clone_lock+0x16/0x170 [ 3641.701213] [<ffffffff807ae449>] tcp_create_openreq_child+0x29/0x820 [ 3641.707663] [<ffffffff807d62e2>] ? ipt_do_table+0x222/0x670 [ 3641.713354] [<ffffffff807aaf5b>] tcp_v4_syn_recv_sock+0xab/0x3d0 [ 3641.719425] [<ffffffff807af63a>] tcp_check_req+0x3da/0x530 [ 3641.724979] [<ffffffff8078b400>] ? inet_hashinfo_init+0x60/0x80 [ 3641.730964] [<ffffffff807ade6f>] ? tcp_v4_rcv+0x79f/0xbe0 [ 3641.736430] [<ffffffff807ab9bd>] tcp_v4_do_rcv+0x38d/0x4f0 [ 3641.741985] [<ffffffff807ae14a>] tcp_v4_rcv+0xa7a/0xbe0 Its safe at this point because the parent socket owns a reference on the netstamp_needed, so we cant have a 0 -> 1 transition, which requires to lock a mutex. Instead of refining the check, lets remove it, as all known callers are safe. If it ever changes in the future, static_key_slow_inc() will complain anyway. Reported-by: Laurent Chavey <chavey@xxxxxxxxxx> Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/core/dev.c | 1 - 1 file changed, 1 deletion(-) --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1591,7 +1591,6 @@ void net_enable_timestamp(void) return; } #endif - WARN_ON(in_interrupt()); static_key_slow_inc(&netstamp_needed); } EXPORT_SYMBOL(net_enable_timestamp); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html