Re: [PATCH v4 2/2] staging: android: Remove BUG from ion_system_heap.c

From: Dan Carpenter
Date: Mon Aug 24 2020 - 07:27:53 EST


On Fri, Aug 21, 2020 at 09:25:26AM -0700, Randy Dunlap wrote:
> On 8/21/20 8:28 AM, Tomer Samara wrote:
> > Remove BUG() from ion_sytem_heap.c
> >
> > this fix the following checkpatch issue:
> > Avoid crashing the kernel - try using WARN_ON &
> > recovery code ratherthan BUG() or BUG_ON().
> >
> > Signed-off-by: Tomer Samara <tomersamara98@xxxxxxxxx>
> > ---
> > drivers/staging/android/ion/ion_system_heap.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/staging/android/ion/ion_system_heap.c b/drivers/staging/android/ion/ion_system_heap.c
> > index eac0632ab4e8..00d6154aec34 100644
> > --- a/drivers/staging/android/ion/ion_system_heap.c
> > +++ b/drivers/staging/android/ion/ion_system_heap.c
> > @@ -30,7 +30,7 @@ static int order_to_index(unsigned int order)
> > for (i = 0; i < NUM_ORDERS; i++)
> > if (order == orders[i])
> > return i;
> > - BUG();
> > + /* This is impossible. */
> > return -1;
> > }
>
> Hi,
> Please explain why this is impossible.
>
> If some caller calls order_to_index(5), it will return -1, yes?
>

I was happy enough with the comment as-is given that I suggested it.
But an alternative comment could be "/* This is impossible.
We always pass valid values to this function. */

regards,
dan carpenter