From: James Smart jsmart2021@gmail.com
[ Upstream commit 03cbbd7c2f5ee288f648f4aeedc765a181188553 ]
During stress I/O tests with 500+ vports, hard LOCKUP call traces are observed.
CPU A: native_queued_spin_lock_slowpath+0x192 _raw_spin_lock_irqsave+0x32 lpfc_handle_fcp_err+0x4c6 lpfc_fcp_io_cmd_wqe_cmpl+0x964 lpfc_sli4_fp_handle_cqe+0x266 __lpfc_sli4_process_cq+0x105 __lpfc_sli4_hba_process_cq+0x3c lpfc_cq_poll_hdler+0x16 irq_poll_softirq+0x76 __softirqentry_text_start+0xe4 irq_exit+0xf7 do_IRQ+0x7f
CPU B: native_queued_spin_lock_slowpath+0x5b _raw_spin_lock+0x1c lpfc_abort_handler+0x13e scmd_eh_abort_handler+0x85 process_one_work+0x1a7 worker_thread+0x30 kthread+0x112 ret_from_fork+0x1f
Diagram of lockup:
CPUA CPUB ---- ---- lpfc_cmd->buf_lock phba->hbalock lpfc_cmd->buf_lock phba->hbalock
Fix by reordering the taking of the lpfc_cmd->buf_lock and phba->hbalock in lpfc_abort_handler routine so that it tries to take the lpfc_cmd->buf_lock first before phba->hbalock.
Link: https://lore.kernel.org/r/20220412222008.126521-7-jsmart2021@gmail.com Co-developed-by: Justin Tee justin.tee@broadcom.com Signed-off-by: Justin Tee justin.tee@broadcom.com Signed-off-by: James Smart jsmart2021@gmail.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/lpfc/lpfc_scsi.c | 33 +++++++++++++++------------------ 1 file changed, 15 insertions(+), 18 deletions(-)
diff --git a/drivers/scsi/lpfc/lpfc_scsi.c b/drivers/scsi/lpfc/lpfc_scsi.c index 3d9175f1b678..8c79264a935b 100644 --- a/drivers/scsi/lpfc/lpfc_scsi.c +++ b/drivers/scsi/lpfc/lpfc_scsi.c @@ -5885,25 +5885,25 @@ lpfc_abort_handler(struct scsi_cmnd *cmnd) if (!lpfc_cmd) return ret;
- spin_lock_irqsave(&phba->hbalock, flags); + /* Guard against IO completion being called at same time */ + spin_lock_irqsave(&lpfc_cmd->buf_lock, flags); + + spin_lock(&phba->hbalock); /* driver queued commands are in process of being flushed */ if (phba->hba_flag & HBA_IOQ_FLUSH) { lpfc_printf_vlog(vport, KERN_WARNING, LOG_FCP, "3168 SCSI Layer abort requested I/O has been " "flushed by LLD.\n"); ret = FAILED; - goto out_unlock; + goto out_unlock_hba; }
- /* Guard against IO completion being called at same time */ - spin_lock(&lpfc_cmd->buf_lock); - if (!lpfc_cmd->pCmd) { lpfc_printf_vlog(vport, KERN_WARNING, LOG_FCP, "2873 SCSI Layer I/O Abort Request IO CMPL Status " "x%x ID %d LUN %llu\n", SUCCESS, cmnd->device->id, cmnd->device->lun); - goto out_unlock_buf; + goto out_unlock_hba; }
iocb = &lpfc_cmd->cur_iocbq; @@ -5911,7 +5911,7 @@ lpfc_abort_handler(struct scsi_cmnd *cmnd) pring_s4 = phba->sli4_hba.hdwq[iocb->hba_wqidx].io_wq->pring; if (!pring_s4) { ret = FAILED; - goto out_unlock_buf; + goto out_unlock_hba; } spin_lock(&pring_s4->ring_lock); } @@ -5944,8 +5944,8 @@ lpfc_abort_handler(struct scsi_cmnd *cmnd) "3389 SCSI Layer I/O Abort Request is pending\n"); if (phba->sli_rev == LPFC_SLI_REV4) spin_unlock(&pring_s4->ring_lock); - spin_unlock(&lpfc_cmd->buf_lock); - spin_unlock_irqrestore(&phba->hbalock, flags); + spin_unlock(&phba->hbalock); + spin_unlock_irqrestore(&lpfc_cmd->buf_lock, flags); goto wait_for_cmpl; }
@@ -5966,15 +5966,13 @@ lpfc_abort_handler(struct scsi_cmnd *cmnd) if (ret_val != IOCB_SUCCESS) { /* Indicate the IO is not being aborted by the driver. */ lpfc_cmd->waitq = NULL; - spin_unlock(&lpfc_cmd->buf_lock); - spin_unlock_irqrestore(&phba->hbalock, flags); ret = FAILED; - goto out; + goto out_unlock_hba; }
/* no longer need the lock after this point */ - spin_unlock(&lpfc_cmd->buf_lock); - spin_unlock_irqrestore(&phba->hbalock, flags); + spin_unlock(&phba->hbalock); + spin_unlock_irqrestore(&lpfc_cmd->buf_lock, flags);
if (phba->cfg_poll & DISABLE_FCP_RING_INT) lpfc_sli_handle_fast_ring_event(phba, @@ -6009,10 +6007,9 @@ lpfc_abort_handler(struct scsi_cmnd *cmnd) out_unlock_ring: if (phba->sli_rev == LPFC_SLI_REV4) spin_unlock(&pring_s4->ring_lock); -out_unlock_buf: - spin_unlock(&lpfc_cmd->buf_lock); -out_unlock: - spin_unlock_irqrestore(&phba->hbalock, flags); +out_unlock_hba: + spin_unlock(&phba->hbalock); + spin_unlock_irqrestore(&lpfc_cmd->buf_lock, flags); out: lpfc_printf_vlog(vport, KERN_WARNING, LOG_FCP, "0749 SCSI Layer I/O Abort Request Status x%x ID %d "