Re: [PATCH v3 4/6] mm: ioremap: Add arch_ioremap/iounmap()

[Kefeng Wang]

On 2022/5/24 20:35, Arnd Bergmann wrote:
> On Tue, May 24, 2022 at 11:48 AM Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> wrote:
> > > > > mm/ioremap.c:59:16: sparse: sparse: incorrect type in argument 1 (different address spaces) @@     expected void const *addr @@     got void [noderef] __iomem *vaddr @@
> > >      mm/ioremap.c:59:16: sparse:     expected void const *addr
> > >      mm/ioremap.c:59:16: sparse:     got void [noderef] __iomem *vaddr
> > >
> > > vim +59 mm/ioremap.c
> > >
> > >       51
> > >       52       void iounmap(volatile void __iomem *addr)
> > >       53       {
> > >       54               void __iomem *vaddr = (void __iomem *)((unsigned long)addr & PAGE_MASK);
> > >       55
> > >       56               if (arch_iounmap(vaddr))
> > >       57                       return;
> > >       58
> > >     > 59               vunmap(vaddr);
> > 1) Will add generic "arch_ioremap/arch_iounmap define"
> >
> > 2) and change this to vunmap((void *)vaddr);
> I think this need an extra __force to actually suppress the sparse
> warning, as in
>
>          vunmap((void __force *)vaddr);
>
> Using __force is usually wrong, this is one of the exceptions, so
> maybe add a comment
> as well.
Right, I found this too， and  using  ___force in local, will update, thank.
>           Arnd
>
> .