On Tue, 2020-07-28 at 16:42 +0800, wanghai (M) wrote:
> 在 2020/7/25 5:29, Joe Perches 写道:
> > On Fri, 2020-07-24 at 21:00 +0800, Wang Hai wrote:
> > > Remove casting the values returned by memory allocation function.
> > >
> > > Coccinelle emits WARNING:
> > >
> > > ./drivers/net/ethernet/cavium/liquidio/octeon_device.c:1155:14-36:
> > > WARNING:
> > > casting value returned by memory allocation function to (struct
> > > octeon_dispatch *) is useless.
> > []
> > > diff --git a/drivers/net/ethernet/cavium/liquidio/octeon_device.c
> > > b/drivers/net/ethernet/cavium/liquidio/octeon_device.c
> > []
> > > @@ -1152,8 +1152,7 @@ octeon_register_dispatch_fn(struct octeon_device
> > > *oct,
> > >
> > > dev_dbg(&oct->pci_dev->dev,
> > > "Adding opcode to dispatch list linked list\n");
> > > - dispatch = (struct octeon_dispatch *)
> > > - vmalloc(sizeof(struct octeon_dispatch));
> > > + dispatch = vmalloc(sizeof(struct octeon_dispatch));
> > More the question is why this is vmalloc at all
> > as the structure size is very small.
> >
> > Likely this should just be kmalloc.
> >
> >
> Thanks for your advice. It is indeed best to use kmalloc here.
> > > if (!dispatch) {
> > > dev_err(&oct->pci_dev->dev,
> > > "No memory to add dispatch function\n");
> > And this dev_err is unnecessary.
> >
> >
> I don't understand why dev_err is not needed here. We can easily know
> that an error has occurred here through dev_err
Memory allocation failures without __GFP_NOWARN. already
do a dump_stack to show the location of the code that
could not successfully allocate memory.
