Re: [PATCH] scsi: lpfc: use spin_lock_irqsave instead of spin_lock_irq in IRQ context

From: James Smart
Date: Fri Aug 16 2019 - 14:29:14 EST


On 8/12/2019 1:31 AM, Fuqian Huang wrote:
As spin_unlock_irq will enable interrupts.
Function lpfc_findnode_rpi is called from
lpfc_sli_abts_err_handler (./drivers/scsi/lpfc/lpfc_sli.c)
<- lpfc_sli_async_event_handler
<- lpfc_sli_process_unsol_iocb
<- lpfc_sli_handle_fast_ring_event
<- lpfc_sli_fp_intr_handler
<- lpfc_sli_intr_handler
and lpfc_sli_intr_handler is an interrupt handler.
Interrupts are enabled in interrupt handler.
Use spin_lock_irqsave/spin_unlock_irqrestore instead of spin_(un)lock_irq
in IRQ context to avoid this.

Signed-off-by: Fuqian Huang <huangfq.daxian@xxxxxxxxx>
---
drivers/scsi/lpfc/lpfc_hbadisc.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_hbadisc.c b/drivers/scsi/lpfc/lpfc_hbadisc.c
index 28ecaa7fc715..cf02c352b324 100644
--- a/drivers/scsi/lpfc/lpfc_hbadisc.c
+++ b/drivers/scsi/lpfc/lpfc_hbadisc.c
@@ -6065,10 +6065,11 @@ lpfc_findnode_rpi(struct lpfc_vport *vport, uint16_t rpi)
{
struct Scsi_Host *shost = lpfc_shost_from_vport(vport);
struct lpfc_nodelist *ndlp;
+ unsigned long flags;
- spin_lock_irq(shost->host_lock);
+ spin_lock_irqsave(shost->host_lock, flags);
ndlp = __lpfc_findnode_rpi(vport, rpi);
- spin_unlock_irq(shost->host_lock);
+ spin_unlock_irqrestore(shost->host_lock, flags);
return ndlp;
}

Thank you.

Reviewed-by: James Smart <james.smart@xxxxxxxxxxxx>

-- james