4.2.8-ckt5 -stable review patch. If anyone has any objections, please let me know.
---8<------------------------------------------------------------ From: Bart Van Assche <[email protected]> commit 9ff9d15eddd13ecdd41876c5e1f31ddbb127101c upstream. This patch fixes the following kernel warning because it avoids that IRQs are disabled while ft_release_cmd() is invoked (fc_seq_set_resp() invokes spin_unlock_bh()): WARNING: CPU: 3 PID: 117 at kernel/softirq.c:150 __local_bh_enable_ip+0xaa/0x110() Call Trace: [<ffffffff814f71eb>] dump_stack+0x4f/0x7b [<ffffffff8105e56a>] warn_slowpath_common+0x8a/0xc0 [<ffffffff8105e65a>] warn_slowpath_null+0x1a/0x20 [<ffffffff81062b2a>] __local_bh_enable_ip+0xaa/0x110 [<ffffffff814ff229>] _raw_spin_unlock_bh+0x39/0x40 [<ffffffffa03a7f94>] fc_seq_set_resp+0xe4/0x100 [libfc] [<ffffffffa02e604a>] ft_free_cmd+0x4a/0x90 [tcm_fc] [<ffffffffa02e6972>] ft_release_cmd+0x12/0x20 [tcm_fc] [<ffffffffa042bd66>] target_release_cmd_kref+0x56/0x90 [target_core_mod] [<ffffffffa042caf0>] target_put_sess_cmd+0xc0/0x110 [target_core_mod] [<ffffffffa042cb81>] transport_release_cmd+0x41/0x70 [target_core_mod] [<ffffffffa042d975>] transport_generic_free_cmd+0x35/0x420 [target_core_mod] Signed-off-by: Bart Van Assche <[email protected]> Acked-by: Joern Engel <[email protected]> Reviewed-by: Andy Grover <[email protected]> Cc: Christoph Hellwig <[email protected]> Cc: Hannes Reinecke <[email protected]> Cc: Sagi Grimberg <[email protected]> Signed-off-by: Nicholas Bellinger <[email protected]> Signed-off-by: Kamal Mostafa <[email protected]> --- drivers/target/target_core_tmr.c | 7 ++++++- drivers/target/target_core_transport.c | 12 ++++++------ 2 files changed, 12 insertions(+), 7 deletions(-) diff --git a/drivers/target/target_core_tmr.c b/drivers/target/target_core_tmr.c index 5b28203..28fb301 100644 --- a/drivers/target/target_core_tmr.c +++ b/drivers/target/target_core_tmr.c @@ -130,6 +130,9 @@ void core_tmr_abort_task( if (tmr->ref_task_tag != ref_tag) continue; + if (!kref_get_unless_zero(&se_cmd->cmd_kref)) + continue; + printk("ABORT_TASK: Found referenced %s task_tag: %llu\n", se_cmd->se_tfo->get_fabric_name(), ref_tag); @@ -139,13 +142,15 @@ void core_tmr_abort_task( " skipping\n", ref_tag); spin_unlock(&se_cmd->t_state_lock); spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); + + target_put_sess_cmd(se_cmd); + goto out; } se_cmd->transport_state |= CMD_T_ABORTED; spin_unlock(&se_cmd->t_state_lock); list_del_init(&se_cmd->se_cmd_list); - kref_get(&se_cmd->cmd_kref); spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); cancel_work_sync(&se_cmd->work); diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index bbf4f69..3098153 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -2468,23 +2468,24 @@ out: EXPORT_SYMBOL(target_get_sess_cmd); static void target_release_cmd_kref(struct kref *kref) - __releases(&se_cmd->se_sess->sess_cmd_lock) { struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref); struct se_session *se_sess = se_cmd->se_sess; + unsigned long flags; + spin_lock_irqsave(&se_sess->sess_cmd_lock, flags); if (list_empty(&se_cmd->se_cmd_list)) { - spin_unlock(&se_sess->sess_cmd_lock); + spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); se_cmd->se_tfo->release_cmd(se_cmd); return; } if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) { - spin_unlock(&se_sess->sess_cmd_lock); + spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); complete(&se_cmd->cmd_wait_comp); return; } list_del(&se_cmd->se_cmd_list); - spin_unlock(&se_sess->sess_cmd_lock); + spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); se_cmd->se_tfo->release_cmd(se_cmd); } @@ -2500,8 +2501,7 @@ int target_put_sess_cmd(struct se_cmd *se_cmd) se_cmd->se_tfo->release_cmd(se_cmd); return 1; } - return kref_put_spinlock_irqsave(&se_cmd->cmd_kref, target_release_cmd_kref, - &se_sess->sess_cmd_lock); + return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref); } EXPORT_SYMBOL(target_put_sess_cmd); -- 2.7.0
