lkml.org 
[lkml]   [2016]   [Feb]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 3.12 096/142] iscsi-target: Fix rx_login_comp hang after login failure
    Date
    From: Nicholas Bellinger <nab@linux-iscsi.org>

    3.12-stable review patch. If anyone has any objections, please let me know.

    ===============

    commit ca82c2bded29b38d36140bfa1e76a7bbfcade390 upstream.

    This patch addresses a case where iscsi_target_do_tx_login_io()
    fails sending the last login response PDU, after the RX/TX
    threads have already been started.

    The case centers around iscsi_target_rx_thread() not invoking
    allow_signal(SIGINT) before the send_sig(SIGINT, ...) occurs
    from the failure path, resulting in RX thread hanging
    indefinately on iscsi_conn->rx_login_comp.

    Note this bug is a regression introduced by:

    commit e54198657b65625085834847ab6271087323ffea
    Author: Nicholas Bellinger <nab@linux-iscsi.org>
    Date: Wed Jul 22 23:14:19 2015 -0700

    iscsi-target: Fix iscsit_start_kthreads failure OOPs

    To address this bug, complete ->rx_login_complete for good
    measure in the failure path, and immediately return from
    RX thread context if connection state did not actually reach
    full feature phase (TARG_CONN_STATE_LOGGED_IN).

    Cc: Sagi Grimberg <sagig@mellanox.com>
    Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
    Signed-off-by: Jiri Slaby <jslaby@suse.cz>
    ---
    drivers/target/iscsi/iscsi_target.c | 13 ++++++++++++-
    drivers/target/iscsi/iscsi_target_nego.c | 1 +
    2 files changed, 13 insertions(+), 1 deletion(-)

    diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c
    index 6f3aa50699f1..9bf13531029e 100644
    --- a/drivers/target/iscsi/iscsi_target.c
    +++ b/drivers/target/iscsi/iscsi_target.c
    @@ -4023,6 +4023,17 @@ reject:
    return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
    }

    +static bool iscsi_target_check_conn_state(struct iscsi_conn *conn)
    +{
    + bool ret;
    +
    + spin_lock_bh(&conn->state_lock);
    + ret = (conn->conn_state != TARG_CONN_STATE_LOGGED_IN);
    + spin_unlock_bh(&conn->state_lock);
    +
    + return ret;
    +}
    +
    int iscsi_target_rx_thread(void *arg)
    {
    int ret, rc;
    @@ -4040,7 +4051,7 @@ int iscsi_target_rx_thread(void *arg)
    * incoming iscsi/tcp socket I/O, and/or failing the connection.
    */
    rc = wait_for_completion_interruptible(&conn->rx_login_comp);
    - if (rc < 0)
    + if (rc < 0 || iscsi_target_check_conn_state(conn))
    return 0;

    if (conn->conn_transport->transport_type == ISCSI_INFINIBAND) {
    diff --git a/drivers/target/iscsi/iscsi_target_nego.c b/drivers/target/iscsi/iscsi_target_nego.c
    index a801cad91742..956fc40df3ff 100644
    --- a/drivers/target/iscsi/iscsi_target_nego.c
    +++ b/drivers/target/iscsi/iscsi_target_nego.c
    @@ -393,6 +393,7 @@ err:
    if (login->login_complete) {
    if (conn->rx_thread && conn->rx_thread_active) {
    send_sig(SIGINT, conn->rx_thread, 1);
    + complete(&conn->rx_login_comp);
    kthread_stop(conn->rx_thread);
    }
    if (conn->tx_thread && conn->tx_thread_active) {
    --
    2.7.1
    \
     
     \ /
      Last update: 2016-02-24 12:21    [W:3.987 / U:0.592 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site