diff options
| author | Trond Myklebust <trond.myklebust@primarydata.com> | 2014-02-11 09:15:54 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-03-06 21:30:08 -0800 |
| commit | 830d5bd83a895818388f874675d3bd76dc470e01 (patch) | |
| tree | 362e1cb333d48a211da3492c7dab71b88e47ea20 | |
| parent | 6319b13bb7e47c75e00cb6a5cabfb448983dc233 (diff) | |
SUNRPC: Fix races in xs_nospace()
commit 06ea0bfe6e6043cb56a78935a19f6f8ebc636226 upstream.
When a send failure occurs due to the socket being out of buffer space,
we call xs_nospace() in order to have the RPC task wait until the
socket has drained enough to make it worth while trying again.
The current patch fixes a race in which the socket is drained before
we get round to setting up the machinery in xs_nospace(), and which
is reported to cause hangs.
Link: http://lkml.kernel.org/r/20140210170315.33dfc621@notabene.brown
Fixes: a9a6b52ee1ba (SUNRPC: Don't start the retransmission timer...)
Reported-by: Neil Brown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | net/sunrpc/xprtsock.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 8a0e04d0928a..fc47165dc254 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -502,6 +502,7 @@ static int xs_nospace(struct rpc_task *task) struct rpc_rqst *req = task->tk_rqstp; struct rpc_xprt *xprt = req->rq_xprt; struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); + struct sock *sk = transport->inet; int ret = -EAGAIN; dprintk("RPC: %5u xmit incomplete (%u left of %u)\n", @@ -519,7 +520,7 @@ static int xs_nospace(struct rpc_task *task) * window size */ set_bit(SOCK_NOSPACE, &transport->sock->flags); - transport->inet->sk_write_pending++; + sk->sk_write_pending++; /* ...and wait for more buffer space */ xprt_wait_for_buffer_space(task, xs_nospace_callback); } @@ -529,6 +530,9 @@ static int xs_nospace(struct rpc_task *task) } spin_unlock_bh(&xprt->transport_lock); + + /* Race breaker in case memory is freed before above code is called */ + sk->sk_write_space(sk); return ret; } |