This is a note to let you know that I've just added the patch titled SUNRPC: Ensure that we wait for connections to complete before retrying to the 4.2-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: sunrpc-ensure-that-we-wait-for-connections-to-complete-before-retrying.patch and it can be found in the queue-4.2 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 0fdea1e8a2853f79d39b8555cc9de16a7e0ab26f Mon Sep 17 00:00:00 2001 From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> Date: Wed, 16 Sep 2015 23:43:17 -0400 Subject: SUNRPC: Ensure that we wait for connections to complete before retrying From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> commit 0fdea1e8a2853f79d39b8555cc9de16a7e0ab26f upstream. Commit 718ba5b87343, moved the responsibility for unlocking the socket to xs_tcp_setup_socket, meaning that the socket will be unlocked before we know that it has finished trying to connect. The following patch is based on an initial patch by Russell King to ensure that we delay clearing the XPRT_CONNECTING flag until we either know that we failed to initiate a connection attempt, or the connection attempt itself failed. Fixes: 718ba5b87343 ("SUNRPC: Add helpers to prevent socket create from racing") Reported-by: Russell King <linux@xxxxxxxxxxxxxxxx> Reported-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx> Tested-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx> Tested-by: Benjamin Coddington <bcodding@xxxxxxxxxx> Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/linux/sunrpc/xprtsock.h | 3 +++ net/sunrpc/xprtsock.c | 11 ++++++++--- 2 files changed, 11 insertions(+), 3 deletions(-) --- a/include/linux/sunrpc/xprtsock.h +++ b/include/linux/sunrpc/xprtsock.h @@ -42,6 +42,7 @@ struct sock_xprt { /* * Connection of transports */ + unsigned long sock_state; struct delayed_work connect_worker; struct sockaddr_storage srcaddr; unsigned short srcport; @@ -76,6 +77,8 @@ struct sock_xprt { */ #define TCP_RPC_REPLY (1UL << 6) +#define XPRT_SOCK_CONNECTING 1U + #endif /* __KERNEL__ */ #endif /* _LINUX_SUNRPC_XPRTSOCK_H */ --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -1433,6 +1433,7 @@ out: static void xs_tcp_state_change(struct sock *sk) { struct rpc_xprt *xprt; + struct sock_xprt *transport; read_lock_bh(&sk->sk_callback_lock); if (!(xprt = xprt_from_sock(sk))) @@ -1444,13 +1445,12 @@ static void xs_tcp_state_change(struct s sock_flag(sk, SOCK_ZAPPED), sk->sk_shutdown); + transport = container_of(xprt, struct sock_xprt, xprt); trace_rpc_socket_state_change(xprt, sk->sk_socket); switch (sk->sk_state) { case TCP_ESTABLISHED: spin_lock(&xprt->transport_lock); if (!xprt_test_and_set_connected(xprt)) { - struct sock_xprt *transport = container_of(xprt, - struct sock_xprt, xprt); /* Reset TCP record info */ transport->tcp_offset = 0; @@ -1459,6 +1459,8 @@ static void xs_tcp_state_change(struct s transport->tcp_flags = TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID; xprt->connect_cookie++; + clear_bit(XPRT_SOCK_CONNECTING, &transport->sock_state); + xprt_clear_connecting(xprt); xprt_wake_pending_tasks(xprt, -EAGAIN); } @@ -1494,6 +1496,9 @@ static void xs_tcp_state_change(struct s smp_mb__after_atomic(); break; case TCP_CLOSE: + if (test_and_clear_bit(XPRT_SOCK_CONNECTING, + &transport->sock_state)) + xprt_clear_connecting(xprt); xs_sock_mark_closed(xprt); } out: @@ -2177,6 +2182,7 @@ static int xs_tcp_finish_connecting(stru /* Tell the socket layer to start connecting... */ xprt->stat.connect_count++; xprt->stat.connect_start = jiffies; + set_bit(XPRT_SOCK_CONNECTING, &transport->sock_state); ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, O_NONBLOCK); switch (ret) { case 0: @@ -2238,7 +2244,6 @@ static void xs_tcp_setup_socket(struct w case -EINPROGRESS: case -EALREADY: xprt_unlock_connect(xprt, transport); - xprt_clear_connecting(xprt); return; case -EINVAL: /* Happens, for instance, if the user specified a link Patches currently in stable-queue which might be from trond.myklebust@xxxxxxxxxxxxxxx are queue-4.2/nfs41-flexfiles-zero-out-ds-write-wcc.patch queue-4.2/nfs-nfs_set_pgio_error-sometimes-misses-errors.patch queue-4.2/nfs-fix-a-null-pointer-dereference-of-migration-recovery-ops-for-v4.2-client.patch queue-4.2/sunrpc-xs_reset_transport-must-mark-the-connection-as-disconnected.patch queue-4.2/nfs-fix-truncated-client-owner-id-without-proto-type.patch queue-4.2/sunrpc-lock-the-transport-layer-on-shutdown.patch queue-4.2/nfs-don-t-let-the-ctime-override-attribute-barriers.patch queue-4.2/sunrpc-fix-a-thinko-in-xs_connect.patch queue-4.2/nfsv4-don-t-set-setattr-for-o_rdonly-o_excl.patch queue-4.2/nfs41-flexfiles-update-inode-after-write-finishes.patch queue-4.2/nfsv4.1-pnfs-fix-borken-function-_same_data_server_addrs_locked.patch queue-4.2/nfsv4-force-a-post-op-attribute-update-when-holding-a-delegation.patch queue-4.2/nfsv4.1-pnfs-fix-atomicity-of-commit-list-updates.patch queue-4.2/nfsv4.1-flexfiles-fix-a-protocol-error-in-layoutreturn.patch queue-4.2/revert-nfsv4-remove-incorrect-check-in-can_open_delegated.patch queue-4.2/sunrpc-ensure-that-we-wait-for-connections-to-complete-before-retrying.patch queue-4.2/nfsv4.1-fix-a-protocol-issue-with-close-stateids.patch -- 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