[PATCH 4.10 21/27] scsi: mpt3sas: Avoid sleeping in interrupt context

Greg Kroah-Hartman
2017-03-24T18:22:36Z

From: Bart Van Assche <bart.vanassche@sandisk.com>

commit 8893cf6cb1cf56334c05120e23092dbfc9423ebb upstream.

Commit 669f044170d8 ("scsi: srp_transport: Move queuecommand() wait code
to SCSI core") can make scsi_internal_device_block() sleep. However,
the mpt3sas driver can call this function from an interrupt
handler. Hence add a second argument to scsi_internal_device_block()
that restores the old behavior of this function for the mpt3sas handler.

The call chain that triggered an "IRQ handler enabled interrupts"
complaint is as follows:

_base_interrupt()
-> _base_async_event()
-> mpt3sas_scsih_event_callback()
-> _scsih_check_topo_delete_events()
-> _scsih_block_io_to_children_attached_directly()
-> _scsih_block_io_device()
-> _scsih_internal_device_block()
-> scsi_internal_device_block()

Reported-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Omar Sandoval <osandov@osandov.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sathya Prakash <sathya.prakash@broadcom.com>
Cc: Chaitra P B <chaitra.basappa@broadcom.com>
Cc: Suganath Prabu Subramani <suganath-prabu.subramani@broadcom.com>
Cc: Sreekanth Reddy <Sreekanth.Reddy@broadcom.com>
Tested-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/scsi/mpt3sas/mpt3sas_base.h | 3 ---
drivers/scsi/mpt3sas/mpt3sas_scsih.c | 4 ++--
drivers/scsi/scsi_lib.c | 14 ++++++++++----
drivers/scsi/scsi_priv.h | 3 ---
include/scsi/scsi_device.h | 4 ++++
5 files changed, 16 insertions(+), 12 deletions(-)

--- a/drivers/scsi/mpt3sas/mpt3sas_base.h
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.h
@@ -1443,9 +1443,6 @@ void mpt3sas_transport_update_links(stru
u64 sas_address, u16 handle, u8 phy_number, u8 link_rate);
extern struct sas_function_template mpt3sas_transport_functions;
extern struct scsi_transport_template *mpt3sas_transport_template;
-extern int scsi_internal_device_block(struct scsi_device *sdev);
-extern int scsi_internal_device_unblock(struct scsi_device *sdev,
- enum scsi_device_state new_state);
/* trigger data externs */
void mpt3sas_send_trigger_data_event(struct MPT3SAS_ADAPTER *ioc,
struct SL_WH_TRIGGERS_EVENT_DATA_T *event_data);
--- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
@@ -2840,7 +2840,7 @@ _scsih_internal_device_block(struct scsi
sas_device_priv_data->sas_target->handle);
sas_device_priv_data->block = 1;

- r = scsi_internal_device_block(sdev);
+ r = scsi_internal_device_block(sdev, false);
if (r == -EINVAL)
sdev_printk(KERN_WARNING, sdev,
"device_block failed with return(%d) for handle(0x%04x)\n",
@@ -2876,7 +2876,7 @@ _scsih_internal_device_unblock(struct sc
"performing a block followed by an unblock\n",
r, sas_device_priv_data->sas_target->handle);
sas_device_priv_data->block = 1;
- r = scsi_internal_device_block(sdev);
+ r = scsi_internal_device_block(sdev, false);
if (r)
sdev_printk(KERN_WARNING, sdev, "retried device_block "
"failed with return(%d) for handle(0x%04x)\n",
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2880,6 +2880,8 @@ EXPORT_SYMBOL(scsi_target_resume);
/**
* scsi_internal_device_block - internal function to put a device temporarily into the SDEV_BLOCK state
* @sdev: device to block
+ * @wait: Whether or not to wait until ongoing .queuecommand() /
+ * .queue_rq() calls have finished.
*
* Block request made by scsi lld's to temporarily stop all
* scsi commands on the specified device. May sleep.
@@ -2897,7 +2899,7 @@ EXPORT_SYMBOL(scsi_target_resume);
* remove the rport mutex lock and unlock calls from srp_queuecommand().
*/
int
-scsi_internal_device_block(struct scsi_device *sdev)
+scsi_internal_device_block(struct scsi_device *sdev, bool wait)
{
struct request_queue *q = sdev->request_queue;
unsigned long flags;
@@ -2917,12 +2919,16 @@ scsi_internal_device_block(struct scsi_d
* request queue.
*/
if (q->mq_ops) {
- blk_mq_quiesce_queue(q);
+ if (wait)
+ blk_mq_quiesce_queue(q);
+ else
+ blk_mq_stop_hw_queues(q);
} else {
spin_lock_irqsave(q->queue_lock, flags);
blk_stop_queue(q);
spin_unlock_irqrestore(q->queue_lock, flags);
- scsi_wait_for_queuecommand(sdev);
+ if (wait)
+ scsi_wait_for_queuecommand(sdev);
}

return 0;
@@ -2984,7 +2990,7 @@ EXPORT_SYMBOL_GPL(scsi_internal_device_u
static void
device_block(struct scsi_device *sdev, void *data)
{
- scsi_internal_device_block(sdev);
+ scsi_internal_device_block(sdev, true);
}

static int
--- a/drivers/scsi/scsi_priv.h
+++ b/drivers/scsi/scsi_priv.h
@@ -189,8 +189,5 @@ static inline void scsi_dh_remove_device
*/

#define SCSI_DEVICE_BLOCK_MAX_TIMEOUT 600 /* units in seconds */
-extern int scsi_internal_device_block(struct scsi_device *sdev);
-extern int scsi_internal_device_unblock(struct scsi_device *sdev,
- enum scsi_device_state new_state);

#endif /* _SCSI_PRIV_H */
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -475,6 +475,10 @@ static inline int scsi_device_created(st
sdev->sdev_state == SDEV_CREATED_BLOCK;
}

+int scsi_internal_device_block(struct scsi_device *sdev, bool wait);
+int scsi_internal_device_unblock(struct scsi_device *sdev,
+ enum scsi_device_state new_state);
+
/* accessor functions for the SCSI parameters */
static inline int scsi_device_sync(struct scsi_device *sdev)
{