Re: [PATCH] sh: cast away __iomem to remove sparse warning

From: Baoquan He
Date: Wed Jun 08 2022 - 00:52:45 EST


On 06/07/22 at 05:56pm, Rob Landley wrote:
>
>
> On 5/30/22 07:09, Baoquan He wrote:
> > Hi,
> >
> > On 05/07/22 at 09:34am, Baoquan He wrote:
> >> LKP reported a sparse warning in arch/sh/kernel/crash_dump.c during
> >> a kdump patchset reviewing:
> >> https://lore.kernel.org/all/202204082128.JKXXDGpa-lkp@xxxxxxxxx/T/#u
> >>
> >> ../arch/sh/kernel/crash_dump.c:23:36: sparse: warning: incorrect type in argument 1 (different address spaces)
> >> ../arch/sh/kernel/crash_dump.c:23:36: sparse: expected void const *addr
> >> ../arch/sh/kernel/crash_dump.c:23:36: sparse: got void [noderef] __iomem *
> >>
> >> This warning happened when __iomem pointer is passed into fucntion
> >> which doesn't expect it. Casting away the __iomem can fix it.
> >
> > This warning was reported by lkp during one patchset posted and
> > reviewing. Since it's not related to the patchset, I just sent it
> > separately so that later code change on arch/sh/kernel/crash_dump.c
> > won't trigger the lkp warning again.
> >
> > [PATCH v5 RESEND 0/3] Convert vmcore to use an iov_iter
> > https://lore.kernel.org/all/20220408090636.560886-2-bhe@xxxxxxxxxx/T/#u
> >
> > Now the above patchset has been merged into linus's tree, please
> > consider taking this patch.
......
> Tested-by: Rob Landley <rob@xxxxxxxxxxx>

Thanks for testing, Rob.

I guess SuperH arch has been in status of no maintenance, however some
generic code change may involve correspondant ARCH change so that we
have to touch arch/sh/.

Hi Andrew,

To avoid annoying warning when modifying crash_dump code, could you
pick this one?

Thanks
Baoquan