• Nicholas Bellinger's avatar
    iscsi-target: Fix delayed logout processing greater than SECONDS_FOR_LOGOUT_COMP · 947dd1ad
    Nicholas Bellinger authored
    [ Upstream commit 105fa2f4 ]
    
    This patch fixes a BUG() in iscsit_close_session() that could be
    triggered when iscsit_logout_post_handler() execution from within
    tx thread context was not run for more than SECONDS_FOR_LOGOUT_COMP
    (15 seconds), and the TCP connection didn't already close before
    then forcing tx thread context to automatically exit.
    
    This would manifest itself during explicit logout as:
    
    [33206.974254] 1 connection(s) still exist for iSCSI session to iqn.1993-08.org.debian:01:3f5523242179
    [33206.980184] INFO: NMI handler (kgdb_nmi_handler) took too long to run: 2100.772 msecs
    [33209.078643] ------------[ cut here ]------------
    [33209.078646] kernel BUG at drivers/target/iscsi/iscsi_target.c:4346!
    
    Normally when explicit logout attempt fails, the tx thread context
    exits and iscsit_close_connection() from rx thread context does the
    extra cleanup once it detects conn->conn_logout_remove has not been
    cleared by the logout type specific post handlers.
    
    To address this special case, if the logout post handler in tx thread
    context detects conn->tx_thread_active has already been cleared, simply
    return and exit in order for existing iscsit_close_connection()
    logic from rx thread context do failed logout cleanup.
    Reported-by: default avatarBart Van Assche <bart.vanassche@sandisk.com>
    Tested-by: default avatarBart Van Assche <bart.vanassche@sandisk.com>
    Cc: Mike Christie <mchristi@redhat.com>
    Cc: Hannes Reinecke <hare@suse.de>
    Cc: Sagi Grimberg <sagig@mellanox.com>
    Cc: stable@vger.kernel.org # 3.14+
    Tested-by: default avatarGary Guo <ghg@datera.io>
    Tested-by: default avatarChu Yuan Lin <cyl@datera.io>
    Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
    Signed-off-by: default avatarSasha Levin <alexander.levin@verizon.com>
    947dd1ad
iscsi_target.c 131 KB