Re: [PATCH net-next] tcp: fix a potential deadlock in tcp_get_info()
From: Eric Dumazet eric.duma...@gmail.com Date: Thu, 21 May 2015 21:51:19 -0700 From: Eric Dumazet eduma...@google.com Taking socket spinlock in tcp_get_info() can deadlock, as inet_diag_dump_icsk() holds the hashinfo-ehash_locks[i], while packet processing can use the reverse locking order. We could avoid this locking for TCP_LISTEN states, but lockdep would certainly get confused as all TCP sockets share same lockdep classes. ... Lets use u64_sync infrastructure instead. As a bonus, 64bit arches get optimized, as these are nop for them. Fixes: 0df48c26d841 (tcp: add tcpi_bytes_acked to tcp_info) Signed-off-by: Eric Dumazet eduma...@google.com This bug exists in 'net' so I've applied it there. Thanks Eric. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next] tcp: fix a potential deadlock in tcp_get_info()
On Fri, 2015-05-22 at 10:56 -0700, Eric Dumazet wrote: On Fri, 2015-05-22 at 13:50 -0400, David Miller wrote: This bug exists in 'net' so I've applied it there. Thanks Eric. Oh thats right, sorry for this, as you'll probably have a conflict when merging net into net-next. Also I am wondering if not explicitly include linux/u64_stats_sync.h could break one arch... -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next] tcp: fix a potential deadlock in tcp_get_info()
From: Eric Dumazet eric.duma...@gmail.com Date: Fri, 22 May 2015 11:08:39 -0700 On Fri, 2015-05-22 at 11:03 -0700, Eric Dumazet wrote: Also I am wondering if not explicitly include linux/u64_stats_sync.h could break one arch... Sorry for the false alarm, we should be good because of snmp.h Right. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next] tcp: fix a potential deadlock in tcp_get_info()
On Fri, 2015-05-22 at 11:03 -0700, Eric Dumazet wrote: Also I am wondering if not explicitly include linux/u64_stats_sync.h could break one arch... Sorry for the false alarm, we should be good because of snmp.h -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next] tcp: fix a potential deadlock in tcp_get_info()
From: Eric Dumazet eric.duma...@gmail.com Date: Fri, 22 May 2015 10:56:36 -0700 On Fri, 2015-05-22 at 13:50 -0400, David Miller wrote: This bug exists in 'net' so I've applied it there. Thanks Eric. Oh thats right, sorry for this, as you'll probably have a conflict when merging net into net-next. I know, but thanks for the heads up. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH net-next] tcp: fix a potential deadlock in tcp_get_info()
On Fri, 2015-05-22 at 13:50 -0400, David Miller wrote: This bug exists in 'net' so I've applied it there. Thanks Eric. Oh thats right, sorry for this, as you'll probably have a conflict when merging net into net-next. Thanks. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
