From 318ddb34b2052f838aa243d07173e2badf3e630e Mon Sep 17 00:00:00 2001 From: Wen Xiong Date: Thu, 20 Sep 2018 19:32:12 -0500 Subject: scsi: ipr: System hung while dlpar adding primary ipr adapter back While dlpar adding primary ipr adapter back, driver goes through adapter initialization then schedule ipr_worker_thread to start te disk scan by dropping the host lock, calling scsi_add_device. Then get the adapter reset request again, so driver does scsi_block_requests, this will cause the scsi_add_device get hung until we unblock. But we can't run ipr_worker_thread to do the unblock because its stuck in scsi_add_device. This patch fixes the issue. [mkp: typo and whitespace fixes] Signed-off-by: Wen Xiong Acked-by: Brian King Signed-off-by: Martin K. Petersen --- drivers/scsi/ipr.c | 106 ++++++++++++++++++++++++++++++----------------------- 1 file changed, 61 insertions(+), 45 deletions(-) (limited to 'drivers/scsi/ipr.c') diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c index f2ec80b0ffc0..271990bc065b 100644 --- a/drivers/scsi/ipr.c +++ b/drivers/scsi/ipr.c @@ -3335,6 +3335,65 @@ static void ipr_release_dump(struct kref *kref) LEAVE; } +static void ipr_add_remove_thread(struct work_struct *work) +{ + unsigned long lock_flags; + struct ipr_resource_entry *res; + struct scsi_device *sdev; + struct ipr_ioa_cfg *ioa_cfg = + container_of(work, struct ipr_ioa_cfg, scsi_add_work_q); + u8 bus, target, lun; + int did_work; + + ENTER; + spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags); + +restart: + do { + did_work = 0; + if (!ioa_cfg->hrrq[IPR_INIT_HRRQ].allow_cmds) { + spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); + return; + } + + list_for_each_entry(res, &ioa_cfg->used_res_q, queue) { + if (res->del_from_ml && res->sdev) { + did_work = 1; + sdev = res->sdev; + if (!scsi_device_get(sdev)) { + if (!res->add_to_ml) + list_move_tail(&res->queue, &ioa_cfg->free_res_q); + else + res->del_from_ml = 0; + spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); + scsi_remove_device(sdev); + scsi_device_put(sdev); + spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags); + } + break; + } + } + } while (did_work); + + list_for_each_entry(res, &ioa_cfg->used_res_q, queue) { + if (res->add_to_ml) { + bus = res->bus; + target = res->target; + lun = res->lun; + res->add_to_ml = 0; + spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); + scsi_add_device(ioa_cfg->host, bus, target, lun); + spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags); + goto restart; + } + } + + ioa_cfg->scan_done = 1; + spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); + kobject_uevent(&ioa_cfg->host->shost_dev.kobj, KOBJ_CHANGE); + LEAVE; +} + /** * ipr_worker_thread - Worker thread * @work: ioa config struct @@ -3349,13 +3408,9 @@ static void ipr_release_dump(struct kref *kref) static void ipr_worker_thread(struct work_struct *work) { unsigned long lock_flags; - struct ipr_resource_entry *res; - struct scsi_device *sdev; struct ipr_dump *dump; struct ipr_ioa_cfg *ioa_cfg = container_of(work, struct ipr_ioa_cfg, work_q); - u8 bus, target, lun; - int did_work; ENTER; spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags); @@ -3393,49 +3448,9 @@ static void ipr_worker_thread(struct work_struct *work) return; } -restart: - do { - did_work = 0; - if (!ioa_cfg->hrrq[IPR_INIT_HRRQ].allow_cmds) { - spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); - return; - } + schedule_work(&ioa_cfg->scsi_add_work_q); - list_for_each_entry(res, &ioa_cfg->used_res_q, queue) { - if (res->del_from_ml && res->sdev) { - did_work = 1; - sdev = res->sdev; - if (!scsi_device_get(sdev)) { - if (!res->add_to_ml) - list_move_tail(&res->queue, &ioa_cfg->free_res_q); - else - res->del_from_ml = 0; - spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); - scsi_remove_device(sdev); - scsi_device_put(sdev); - spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags); - } - break; - } - } - } while (did_work); - - list_for_each_entry(res, &ioa_cfg->used_res_q, queue) { - if (res->add_to_ml) { - bus = res->bus; - target = res->target; - lun = res->lun; - res->add_to_ml = 0; - spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); - scsi_add_device(ioa_cfg->host, bus, target, lun); - spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags); - goto restart; - } - } - - ioa_cfg->scan_done = 1; spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); - kobject_uevent(&ioa_cfg->host->shost_dev.kobj, KOBJ_CHANGE); LEAVE; } @@ -9933,6 +9948,7 @@ static void ipr_init_ioa_cfg(struct ipr_ioa_cfg *ioa_cfg, INIT_LIST_HEAD(&ioa_cfg->free_res_q); INIT_LIST_HEAD(&ioa_cfg->used_res_q); INIT_WORK(&ioa_cfg->work_q, ipr_worker_thread); + INIT_WORK(&ioa_cfg->scsi_add_work_q, ipr_add_remove_thread); init_waitqueue_head(&ioa_cfg->reset_wait_q); init_waitqueue_head(&ioa_cfg->msi_wait_q); init_waitqueue_head(&ioa_cfg->eeh_wait_q); -- cgit v1.2.3-59-g8ed1b