Re: [PATCH] [SCSI] wd719x: Avoid calling request_firmware under spinlock

[John Garry]

On 15/09/2016 15:08, John Garry wrote:
> On 15/09/2016 14:48, Vaishali Thakkar wrote:
> > It is preferrable to use request_firmware where sleeping is
> > allowed. Using it under spinlock can cause blocking. Here,
> > the function wd719x_chip_init calls request_firmware while
> > holding a spinlock. So, let's access it outside the spinlock.
> >
> > Coccinelle is used to detect the issue.
> >
> > Signed-off-by: Vaishali Thakkar <vaishali.thakkar@xxxxxxxxxx>
> > ---
> > Please note that the patch is compile-tested only. And this change
> > may require driver testing.
> > ---
> >  drivers/scsi/wd719x.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/scsi/wd719x.c b/drivers/scsi/wd719x.c
> > index e3da1a2..b8e57f3 100644
> > --- a/drivers/scsi/wd719x.c
> > +++ b/drivers/scsi/wd719x.c
> > @@ -518,13 +518,14 @@ static int wd719x_host_reset(struct scsi_cmnd *cmd)
> >      int result;
> >
> >      dev_info(&wd->pdev->dev, "host reset requested\n");
> > -    spin_lock_irqsave(wd->sh->host_lock, flags);
> > +
>
> In the version of code I have flags is only used for this spinlock, so
> can flags be removed?

I see we're just relocating the spinlock, so ignore me

> >      /* Try to reinit the RISC */
> >      if (wd719x_chip_init(wd) == 0)
> >          result = SUCCESS;
> >      else
> >          result = FAILED;
> >
> > +    spin_lock_irqsave(wd->sh->host_lock, flags);
> >      /* flush all SCBs */
> >      list_for_each_entry_safe(scb, tmp, &wd->active_scbs, list) {
> >          struct scsi_cmnd *tmp_cmd = scb->cmd;
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>
> .