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* [PATCH] Revert "target/core: Inline transport_lun_remove_cmd()"
@ 2020-02-10  5:12 ` Bart Van Assche
  0 siblings, 0 replies; 6+ messages in thread
From: Bart Van Assche @ 2020-02-10  5:12 UTC (permalink / raw)
  To: Martin K . Petersen
  Cc: target-devel, Bart Van Assche, Pavel Zakharov, Mike Christie, stable

Commit 83f85b8ec305 postponed the percpu_ref_put(&se_cmd->se_lun->lun_ref)
call from command completion to the time when the final command reference
is dropped. That approach is not compatible with the iSCSI target driver
because the iSCSI target driver keeps the command with the highest stat_sn
after it has completed until the next command is received (see also
iscsit_ack_from_expstatsn()). Fix this regression by reverting commit
83f85b8ec305.

Reported-by: Pavel Zakharov <pavel.zakharov@delphix.com>
Cc: Pavel Zakharov <pavel.zakharov@delphix.com>
Cc: Mike Christie <mchristi@redhat.com>
Cc: <stable@vger.kernel.org>
Fixes: 83f85b8ec305 ("scsi: target/core: Inline transport_lun_remove_cmd()")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
 drivers/target/target_core_transport.c | 31 +++++++++++++++++++++++---
 1 file changed, 28 insertions(+), 3 deletions(-)

diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index ea482d4b1f00..0ae9e60fc4d5 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -666,6 +666,11 @@ static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 
 	target_remove_from_state_list(cmd);
 
+	/*
+	 * Clear struct se_cmd->se_lun before the handoff to FE.
+	 */
+	cmd->se_lun = NULL;
+
 	spin_lock_irqsave(&cmd->t_state_lock, flags);
 	/*
 	 * Determine if frontend context caller is requesting the stopping of
@@ -693,6 +698,17 @@ static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 	return cmd->se_tfo->check_stop_free(cmd);
 }
 
+static void transport_lun_remove_cmd(struct se_cmd *cmd)
+{
+	struct se_lun *lun = cmd->se_lun;
+
+	if (!lun)
+		return;
+
+	if (cmpxchg(&cmd->lun_ref_active, true, false))
+		percpu_ref_put(&lun->lun_ref);
+}
+
 static void target_complete_failure_work(struct work_struct *work)
 {
 	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
@@ -783,6 +799,8 @@ static void target_handle_abort(struct se_cmd *cmd)
 
 	WARN_ON_ONCE(kref_read(&cmd->cmd_kref) = 0);
 
+	transport_lun_remove_cmd(cmd);
+
 	transport_cmd_check_stop_to_fabric(cmd);
 }
 
@@ -1708,6 +1726,7 @@ static void target_complete_tmr_failure(struct work_struct *work)
 	se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
 	se_cmd->se_tfo->queue_tm_rsp(se_cmd);
 
+	transport_lun_remove_cmd(se_cmd);
 	transport_cmd_check_stop_to_fabric(se_cmd);
 }
 
@@ -1898,6 +1917,7 @@ void transport_generic_request_failure(struct se_cmd *cmd,
 		goto queue_full;
 
 check_stop:
+	transport_lun_remove_cmd(cmd);
 	transport_cmd_check_stop_to_fabric(cmd);
 	return;
 
@@ -2195,6 +2215,7 @@ static void transport_complete_qf(struct se_cmd *cmd)
 		transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
 		return;
 	}
+	transport_lun_remove_cmd(cmd);
 	transport_cmd_check_stop_to_fabric(cmd);
 }
 
@@ -2289,6 +2310,7 @@ static void target_complete_ok_work(struct work_struct *work)
 		if (ret)
 			goto queue_full;
 
+		transport_lun_remove_cmd(cmd);
 		transport_cmd_check_stop_to_fabric(cmd);
 		return;
 	}
@@ -2314,6 +2336,7 @@ static void target_complete_ok_work(struct work_struct *work)
 			if (ret)
 				goto queue_full;
 
+			transport_lun_remove_cmd(cmd);
 			transport_cmd_check_stop_to_fabric(cmd);
 			return;
 		}
@@ -2349,6 +2372,7 @@ static void target_complete_ok_work(struct work_struct *work)
 			if (ret)
 				goto queue_full;
 
+			transport_lun_remove_cmd(cmd);
 			transport_cmd_check_stop_to_fabric(cmd);
 			return;
 		}
@@ -2384,6 +2408,7 @@ static void target_complete_ok_work(struct work_struct *work)
 		break;
 	}
 
+	transport_lun_remove_cmd(cmd);
 	transport_cmd_check_stop_to_fabric(cmd);
 	return;
 
@@ -2710,6 +2735,9 @@ int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
 		 */
 		if (cmd->state_active)
 			target_remove_from_state_list(cmd);
+
+		if (cmd->se_lun)
+			transport_lun_remove_cmd(cmd);
 	}
 	if (aborted)
 		cmd->free_compl = &compl;
@@ -2781,9 +2809,6 @@ static void target_release_cmd_kref(struct kref *kref)
 	struct completion *abrt_compl = se_cmd->abrt_compl;
 	unsigned long flags;
 
-	if (se_cmd->lun_ref_active)
-		percpu_ref_put(&se_cmd->se_lun->lun_ref);
-
 	if (se_sess) {
 		spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
 		list_del_init(&se_cmd->se_cmd_list);

^ permalink raw reply related	[flat|nested] 6+ messages in thread
* [PATCH] Revert "target/core: Inline transport_lun_remove_cmd()"
@ 2020-02-10  5:12 ` Bart Van Assche
  0 siblings, 0 replies; 6+ messages in thread
From: Bart Van Assche @ 2020-02-10  5:12 UTC (permalink / raw)
  To: Martin K . Petersen
  Cc: target-devel, Bart Van Assche, Pavel Zakharov, Mike Christie, stable

Commit 83f85b8ec305 postponed the percpu_ref_put(&se_cmd->se_lun->lun_ref)
call from command completion to the time when the final command reference
is dropped. That approach is not compatible with the iSCSI target driver
because the iSCSI target driver keeps the command with the highest stat_sn
after it has completed until the next command is received (see also
iscsit_ack_from_expstatsn()). Fix this regression by reverting commit
83f85b8ec305.

Reported-by: Pavel Zakharov <pavel.zakharov@delphix.com>
Cc: Pavel Zakharov <pavel.zakharov@delphix.com>
Cc: Mike Christie <mchristi@redhat.com>
Cc: <stable@vger.kernel.org>
Fixes: 83f85b8ec305 ("scsi: target/core: Inline transport_lun_remove_cmd()")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
 drivers/target/target_core_transport.c | 31 +++++++++++++++++++++++---
 1 file changed, 28 insertions(+), 3 deletions(-)

diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index ea482d4b1f00..0ae9e60fc4d5 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -666,6 +666,11 @@ static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 
 	target_remove_from_state_list(cmd);
 
+	/*
+	 * Clear struct se_cmd->se_lun before the handoff to FE.
+	 */
+	cmd->se_lun = NULL;
+
 	spin_lock_irqsave(&cmd->t_state_lock, flags);
 	/*
 	 * Determine if frontend context caller is requesting the stopping of
@@ -693,6 +698,17 @@ static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 	return cmd->se_tfo->check_stop_free(cmd);
 }
 
+static void transport_lun_remove_cmd(struct se_cmd *cmd)
+{
+	struct se_lun *lun = cmd->se_lun;
+
+	if (!lun)
+		return;
+
+	if (cmpxchg(&cmd->lun_ref_active, true, false))
+		percpu_ref_put(&lun->lun_ref);
+}
+
 static void target_complete_failure_work(struct work_struct *work)
 {
 	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
@@ -783,6 +799,8 @@ static void target_handle_abort(struct se_cmd *cmd)
 
 	WARN_ON_ONCE(kref_read(&cmd->cmd_kref) == 0);
 
+	transport_lun_remove_cmd(cmd);
+
 	transport_cmd_check_stop_to_fabric(cmd);
 }
 
@@ -1708,6 +1726,7 @@ static void target_complete_tmr_failure(struct work_struct *work)
 	se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
 	se_cmd->se_tfo->queue_tm_rsp(se_cmd);
 
+	transport_lun_remove_cmd(se_cmd);
 	transport_cmd_check_stop_to_fabric(se_cmd);
 }
 
@@ -1898,6 +1917,7 @@ void transport_generic_request_failure(struct se_cmd *cmd,
 		goto queue_full;
 
 check_stop:
+	transport_lun_remove_cmd(cmd);
 	transport_cmd_check_stop_to_fabric(cmd);
 	return;
 
@@ -2195,6 +2215,7 @@ static void transport_complete_qf(struct se_cmd *cmd)
 		transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
 		return;
 	}
+	transport_lun_remove_cmd(cmd);
 	transport_cmd_check_stop_to_fabric(cmd);
 }
 
@@ -2289,6 +2310,7 @@ static void target_complete_ok_work(struct work_struct *work)
 		if (ret)
 			goto queue_full;
 
+		transport_lun_remove_cmd(cmd);
 		transport_cmd_check_stop_to_fabric(cmd);
 		return;
 	}
@@ -2314,6 +2336,7 @@ static void target_complete_ok_work(struct work_struct *work)
 			if (ret)
 				goto queue_full;
 
+			transport_lun_remove_cmd(cmd);
 			transport_cmd_check_stop_to_fabric(cmd);
 			return;
 		}
@@ -2349,6 +2372,7 @@ static void target_complete_ok_work(struct work_struct *work)
 			if (ret)
 				goto queue_full;
 
+			transport_lun_remove_cmd(cmd);
 			transport_cmd_check_stop_to_fabric(cmd);
 			return;
 		}
@@ -2384,6 +2408,7 @@ static void target_complete_ok_work(struct work_struct *work)
 		break;
 	}
 
+	transport_lun_remove_cmd(cmd);
 	transport_cmd_check_stop_to_fabric(cmd);
 	return;
 
@@ -2710,6 +2735,9 @@ int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
 		 */
 		if (cmd->state_active)
 			target_remove_from_state_list(cmd);
+
+		if (cmd->se_lun)
+			transport_lun_remove_cmd(cmd);
 	}
 	if (aborted)
 		cmd->free_compl = &compl;
@@ -2781,9 +2809,6 @@ static void target_release_cmd_kref(struct kref *kref)
 	struct completion *abrt_compl = se_cmd->abrt_compl;
 	unsigned long flags;
 
-	if (se_cmd->lun_ref_active)
-		percpu_ref_put(&se_cmd->se_lun->lun_ref);
-
 	if (se_sess) {
 		spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
 		list_del_init(&se_cmd->se_cmd_list);

^ permalink raw reply related	[flat|nested] 6+ messages in thread
* Re: [PATCH] Revert "target/core: Inline transport_lun_remove_cmd()"
  2020-02-10  5:12 ` Bart Van Assche
@ 2020-02-10 15:35   ` Pavel Zakharov
  -1 siblings, 0 replies; 6+ messages in thread
From: Pavel Zakharov @ 2020-02-10 15:35 UTC (permalink / raw)
  To: Bart Van Assche; +Cc: Martin K . Petersen, target-devel, Mike Christie, stable

Thank you Bart for such a fast response!

This LGTM.

Pavel

> On Feb 10, 2020, at 12:12 AM, Bart Van Assche <bvanassche@acm.org> wrote:
> 
> Commit 83f85b8ec305 postponed the percpu_ref_put(&se_cmd->se_lun->lun_ref)
> call from command completion to the time when the final command reference
> is dropped. That approach is not compatible with the iSCSI target driver
> because the iSCSI target driver keeps the command with the highest stat_sn
> after it has completed until the next command is received (see also
> iscsit_ack_from_expstatsn()). Fix this regression by reverting commit
> 83f85b8ec305.
> 
> Reported-by: Pavel Zakharov <pavel.zakharov@delphix.com>
> Cc: Pavel Zakharov <pavel.zakharov@delphix.com>
> Cc: Mike Christie <mchristi@redhat.com>
> Cc: <stable@vger.kernel.org>
> Fixes: 83f85b8ec305 ("scsi: target/core: Inline transport_lun_remove_cmd()")
> Signed-off-by: Bart Van Assche <bvanassche@acm.org>
> ---
> drivers/target/target_core_transport.c | 31 +++++++++++++++++++++++---
> 1 file changed, 28 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
> index ea482d4b1f00..0ae9e60fc4d5 100644
> --- a/drivers/target/target_core_transport.c
> +++ b/drivers/target/target_core_transport.c
> @@ -666,6 +666,11 @@ static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
> 
> 	target_remove_from_state_list(cmd);
> 
> +	/*
> +	 * Clear struct se_cmd->se_lun before the handoff to FE.
> +	 */
> +	cmd->se_lun = NULL;
> +
> 	spin_lock_irqsave(&cmd->t_state_lock, flags);
> 	/*
> 	 * Determine if frontend context caller is requesting the stopping of
> @@ -693,6 +698,17 @@ static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
> 	return cmd->se_tfo->check_stop_free(cmd);
> }
> 
> +static void transport_lun_remove_cmd(struct se_cmd *cmd)
> +{
> +	struct se_lun *lun = cmd->se_lun;
> +
> +	if (!lun)
> +		return;
> +
> +	if (cmpxchg(&cmd->lun_ref_active, true, false))
> +		percpu_ref_put(&lun->lun_ref);
> +}
> +
> static void target_complete_failure_work(struct work_struct *work)
> {
> 	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
> @@ -783,6 +799,8 @@ static void target_handle_abort(struct se_cmd *cmd)
> 
> 	WARN_ON_ONCE(kref_read(&cmd->cmd_kref) == 0);
> 
> +	transport_lun_remove_cmd(cmd);
> +
> 	transport_cmd_check_stop_to_fabric(cmd);
> }
> 
> @@ -1708,6 +1726,7 @@ static void target_complete_tmr_failure(struct work_struct *work)
> 	se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
> 	se_cmd->se_tfo->queue_tm_rsp(se_cmd);
> 
> +	transport_lun_remove_cmd(se_cmd);
> 	transport_cmd_check_stop_to_fabric(se_cmd);
> }
> 
> @@ -1898,6 +1917,7 @@ void transport_generic_request_failure(struct se_cmd *cmd,
> 		goto queue_full;
> 
> check_stop:
> +	transport_lun_remove_cmd(cmd);
> 	transport_cmd_check_stop_to_fabric(cmd);
> 	return;
> 
> @@ -2195,6 +2215,7 @@ static void transport_complete_qf(struct se_cmd *cmd)
> 		transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
> 		return;
> 	}
> +	transport_lun_remove_cmd(cmd);
> 	transport_cmd_check_stop_to_fabric(cmd);
> }
> 
> @@ -2289,6 +2310,7 @@ static void target_complete_ok_work(struct work_struct *work)
> 		if (ret)
> 			goto queue_full;
> 
> +		transport_lun_remove_cmd(cmd);
> 		transport_cmd_check_stop_to_fabric(cmd);
> 		return;
> 	}
> @@ -2314,6 +2336,7 @@ static void target_complete_ok_work(struct work_struct *work)
> 			if (ret)
> 				goto queue_full;
> 
> +			transport_lun_remove_cmd(cmd);
> 			transport_cmd_check_stop_to_fabric(cmd);
> 			return;
> 		}
> @@ -2349,6 +2372,7 @@ static void target_complete_ok_work(struct work_struct *work)
> 			if (ret)
> 				goto queue_full;
> 
> +			transport_lun_remove_cmd(cmd);
> 			transport_cmd_check_stop_to_fabric(cmd);
> 			return;
> 		}
> @@ -2384,6 +2408,7 @@ static void target_complete_ok_work(struct work_struct *work)
> 		break;
> 	}
> 
> +	transport_lun_remove_cmd(cmd);
> 	transport_cmd_check_stop_to_fabric(cmd);
> 	return;
> 
> @@ -2710,6 +2735,9 @@ int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
> 		 */
> 		if (cmd->state_active)
> 			target_remove_from_state_list(cmd);
> +
> +		if (cmd->se_lun)
> +			transport_lun_remove_cmd(cmd);
> 	}
> 	if (aborted)
> 		cmd->free_compl = &compl;
> @@ -2781,9 +2809,6 @@ static void target_release_cmd_kref(struct kref *kref)
> 	struct completion *abrt_compl = se_cmd->abrt_compl;
> 	unsigned long flags;
> 
> -	if (se_cmd->lun_ref_active)
> -		percpu_ref_put(&se_cmd->se_lun->lun_ref);
> -
> 	if (se_sess) {
> 		spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
> 		list_del_init(&se_cmd->se_cmd_list);

^ permalink raw reply	[flat|nested] 6+ messages in thread
* Re: [PATCH] Revert "target/core: Inline transport_lun_remove_cmd()"
@ 2020-02-10 15:35   ` Pavel Zakharov
  0 siblings, 0 replies; 6+ messages in thread
From: Pavel Zakharov @ 2020-02-10 15:35 UTC (permalink / raw)
  To: Bart Van Assche; +Cc: Martin K . Petersen, target-devel, Mike Christie, stable

Thank you Bart for such a fast response!

This LGTM.

Pavel

> On Feb 10, 2020, at 12:12 AM, Bart Van Assche <bvanassche@acm.org> wrote:
> 
> Commit 83f85b8ec305 postponed the percpu_ref_put(&se_cmd->se_lun->lun_ref)
> call from command completion to the time when the final command reference
> is dropped. That approach is not compatible with the iSCSI target driver
> because the iSCSI target driver keeps the command with the highest stat_sn
> after it has completed until the next command is received (see also
> iscsit_ack_from_expstatsn()). Fix this regression by reverting commit
> 83f85b8ec305.
> 
> Reported-by: Pavel Zakharov <pavel.zakharov@delphix.com>
> Cc: Pavel Zakharov <pavel.zakharov@delphix.com>
> Cc: Mike Christie <mchristi@redhat.com>
> Cc: <stable@vger.kernel.org>
> Fixes: 83f85b8ec305 ("scsi: target/core: Inline transport_lun_remove_cmd()")
> Signed-off-by: Bart Van Assche <bvanassche@acm.org>
> ---
> drivers/target/target_core_transport.c | 31 +++++++++++++++++++++++---
> 1 file changed, 28 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
> index ea482d4b1f00..0ae9e60fc4d5 100644
> --- a/drivers/target/target_core_transport.c
> +++ b/drivers/target/target_core_transport.c
> @@ -666,6 +666,11 @@ static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
> 
> 	target_remove_from_state_list(cmd);
> 
> +	/*
> +	 * Clear struct se_cmd->se_lun before the handoff to FE.
> +	 */
> +	cmd->se_lun = NULL;
> +
> 	spin_lock_irqsave(&cmd->t_state_lock, flags);
> 	/*
> 	 * Determine if frontend context caller is requesting the stopping of
> @@ -693,6 +698,17 @@ static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
> 	return cmd->se_tfo->check_stop_free(cmd);
> }
> 
> +static void transport_lun_remove_cmd(struct se_cmd *cmd)
> +{
> +	struct se_lun *lun = cmd->se_lun;
> +
> +	if (!lun)
> +		return;
> +
> +	if (cmpxchg(&cmd->lun_ref_active, true, false))
> +		percpu_ref_put(&lun->lun_ref);
> +}
> +
> static void target_complete_failure_work(struct work_struct *work)
> {
> 	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
> @@ -783,6 +799,8 @@ static void target_handle_abort(struct se_cmd *cmd)
> 
> 	WARN_ON_ONCE(kref_read(&cmd->cmd_kref) == 0);
> 
> +	transport_lun_remove_cmd(cmd);
> +
> 	transport_cmd_check_stop_to_fabric(cmd);
> }
> 
> @@ -1708,6 +1726,7 @@ static void target_complete_tmr_failure(struct work_struct *work)
> 	se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
> 	se_cmd->se_tfo->queue_tm_rsp(se_cmd);
> 
> +	transport_lun_remove_cmd(se_cmd);
> 	transport_cmd_check_stop_to_fabric(se_cmd);
> }
> 
> @@ -1898,6 +1917,7 @@ void transport_generic_request_failure(struct se_cmd *cmd,
> 		goto queue_full;
> 
> check_stop:
> +	transport_lun_remove_cmd(cmd);
> 	transport_cmd_check_stop_to_fabric(cmd);
> 	return;
> 
> @@ -2195,6 +2215,7 @@ static void transport_complete_qf(struct se_cmd *cmd)
> 		transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
> 		return;
> 	}
> +	transport_lun_remove_cmd(cmd);
> 	transport_cmd_check_stop_to_fabric(cmd);
> }
> 
> @@ -2289,6 +2310,7 @@ static void target_complete_ok_work(struct work_struct *work)
> 		if (ret)
> 			goto queue_full;
> 
> +		transport_lun_remove_cmd(cmd);
> 		transport_cmd_check_stop_to_fabric(cmd);
> 		return;
> 	}
> @@ -2314,6 +2336,7 @@ static void target_complete_ok_work(struct work_struct *work)
> 			if (ret)
> 				goto queue_full;
> 
> +			transport_lun_remove_cmd(cmd);
> 			transport_cmd_check_stop_to_fabric(cmd);
> 			return;
> 		}
> @@ -2349,6 +2372,7 @@ static void target_complete_ok_work(struct work_struct *work)
> 			if (ret)
> 				goto queue_full;
> 
> +			transport_lun_remove_cmd(cmd);
> 			transport_cmd_check_stop_to_fabric(cmd);
> 			return;
> 		}
> @@ -2384,6 +2408,7 @@ static void target_complete_ok_work(struct work_struct *work)
> 		break;
> 	}
> 
> +	transport_lun_remove_cmd(cmd);
> 	transport_cmd_check_stop_to_fabric(cmd);
> 	return;
> 
> @@ -2710,6 +2735,9 @@ int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
> 		 */
> 		if (cmd->state_active)
> 			target_remove_from_state_list(cmd);
> +
> +		if (cmd->se_lun)
> +			transport_lun_remove_cmd(cmd);
> 	}
> 	if (aborted)
> 		cmd->free_compl = &compl;
> @@ -2781,9 +2809,6 @@ static void target_release_cmd_kref(struct kref *kref)
> 	struct completion *abrt_compl = se_cmd->abrt_compl;
> 	unsigned long flags;
> 
> -	if (se_cmd->lun_ref_active)
> -		percpu_ref_put(&se_cmd->se_lun->lun_ref);
> -
> 	if (se_sess) {
> 		spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
> 		list_del_init(&se_cmd->se_cmd_list);


^ permalink raw reply	[flat|nested] 6+ messages in thread
* Re: [PATCH] Revert "target/core: Inline transport_lun_remove_cmd()"
  2020-02-10  5:12 ` Bart Van Assche
@ 2020-02-12 23:51   ` Martin K. Petersen
  -1 siblings, 0 replies; 6+ messages in thread
From: Martin K. Petersen @ 2020-02-12 23:51 UTC (permalink / raw)
  To: Bart Van Assche
  Cc: Martin K . Petersen, target-devel, Pavel Zakharov, Mike Christie, stable


Bart,

> Commit 83f85b8ec305 postponed the percpu_ref_put(&se_cmd->se_lun->lun_ref)
> call from command completion to the time when the final command reference is
> dropped. That approach is not compatible with the iSCSI target driver
> because the iSCSI target driver keeps the command with the highest stat_sn
> after it has completed until the next command is received (see also
> iscsit_ack_from_expstatsn()). Fix this regression by reverting commit
> 83f85b8ec305.

Applied to 5.6/scsi-fixes, thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering

^ permalink raw reply	[flat|nested] 6+ messages in thread
* Re: [PATCH] Revert "target/core: Inline transport_lun_remove_cmd()"
@ 2020-02-12 23:51   ` Martin K. Petersen
  0 siblings, 0 replies; 6+ messages in thread
From: Martin K. Petersen @ 2020-02-12 23:51 UTC (permalink / raw)
  To: Bart Van Assche
  Cc: Martin K . Petersen, target-devel, Pavel Zakharov, Mike Christie, stable


Bart,

> Commit 83f85b8ec305 postponed the percpu_ref_put(&se_cmd->se_lun->lun_ref)
> call from command completion to the time when the final command reference is
> dropped. That approach is not compatible with the iSCSI target driver
> because the iSCSI target driver keeps the command with the highest stat_sn
> after it has completed until the next command is received (see also
> iscsit_ack_from_expstatsn()). Fix this regression by reverting commit
> 83f85b8ec305.

Applied to 5.6/scsi-fixes, thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering

^ permalink raw reply	[flat|nested] 6+ messages in thread
end of thread, other threads:[~2020-02-12 23:51 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-02-10  5:12 [PATCH] Revert "target/core: Inline transport_lun_remove_cmd()" Bart Van Assche
2020-02-10  5:12 ` Bart Van Assche
2020-02-10 15:35 ` Pavel Zakharov
2020-02-10 15:35   ` Pavel Zakharov
2020-02-12 23:51 ` Martin K. Petersen
2020-02-12 23:51   ` Martin K. Petersen

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