diff options
| author |   Florian Westphal <fw@strlen.de> | 2018-01-19 14:36:29 +0100 |
|---|---|---|
| committer |   Nicholas Bellinger <nab@linux-iscsi.org> | 2018-01-23 23:03:54 -0800 |
| commit | 1c130ae00b769a2e2df41bad3d6051ee8234b636 (patch) | |
| tree | 94b33dedbc52fa29984aeb59e6bfa79c4d14025b /drivers/target | |
| parent | tcmu: Fix trailing semicolon (diff) | |
| download | linux-dev-1c130ae00b769a2e2df41bad3d6051ee8234b636.tar.xz linux-dev-1c130ae00b769a2e2df41bad3d6051ee8234b636.zip | |
iscsi-target: make sure to wake up sleeping login worker
Mike Christie reports:
Starting in 4.14 iscsi logins will fail around 50% of the time.
Problem appears to be that iscsi_target_sk_data_ready() callback may
return without doing anything in case it finds the login work queue
is still blocked in sock_recvmsg().
Nicholas Bellinger says:
It would indicate users providing their own ->sk_data_ready() callback
must be responsible for waking up a kthread context blocked on
sock_recvmsg(..., MSG_WAITALL), when a second ->sk_data_ready() is
received before the first sock_recvmsg(..., MSG_WAITALL) completes.
So, do this and invoke the original data_ready() callback -- in
case of tcp sockets this takes care of waking the thread.
Disclaimer: I do not understand why this problem did not show up before
tcp prequeue removal.
(Drop WARN_ON usage - nab)
Reported-by: Mike Christie <mchristi@redhat.com>
Bisected-by: Mike Christie <mchristi@redhat.com>
Tested-by: Mike Christie <mchristi@redhat.com>
Diagnosed-by: Nicholas Bellinger <nab@linux-iscsi.org>
Fixes: e7942d0633c4 ("tcp: remove prequeue support")
Signed-off-by: Florian Westphal <fw@strlen.de>
Cc: stable@vger.kernel.org # 4.14+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Diffstat (limited to 'drivers/target')
| -rw-r--r-- | drivers/target/iscsi/iscsi_target_nego.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/target/iscsi/iscsi_target_nego.c b/drivers/target/iscsi/iscsi_target_nego.c index b686e2ce9c0e..8a5e8d17a942 100644 --- a/drivers/target/iscsi/iscsi_target_nego.c +++ b/drivers/target/iscsi/iscsi_target_nego.c @@ -432,6 +432,9 @@ static void iscsi_target_sk_data_ready(struct sock *sk) if (test_and_set_bit(LOGIN_FLAGS_READ_ACTIVE, &conn->login_flags)) { write_unlock_bh(&sk->sk_callback_lock); pr_debug("Got LOGIN_FLAGS_READ_ACTIVE=1, conn: %p >>>>\n", conn); + if (iscsi_target_sk_data_ready == conn->orig_data_ready) + return; + conn->orig_data_ready(sk); return; } |