[PATCH] m68k: don't select ARCH_HAS_DMA_PREP_COHERENT for nommu or coldfire

[PATCH] m68k: don't select ARCH_HAS_DMA_PREP_COHERENT for nommu or coldfire

[Christoph Hellwig]

m68k only provides the dma_prep_coherent symbol when an mmu is enabled
and not on the coldfire platform.  Fix the Kconfig symbol selection
up to match this.

Fixes: 69878ef47562 ("m68k: Implement arch_dma_prep_coherent()")
Reported-by: Guenter Roeck <linux@roeck-us.net>
---
 arch/m68k/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
index 8f765cfefca6..c518d695c376 100644
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -5,7 +5,7 @@ config M68K
 	select ARCH_32BIT_OFF_T
 	select ARCH_HAS_BINFMT_FLAT
 	select ARCH_HAS_DMA_MMAP_PGPROT if MMU && !COLDFIRE
-	select ARCH_HAS_DMA_PREP_COHERENT
+	select ARCH_HAS_DMA_PREP_COHERENT if HAS_DMA && MMU && !COLDFIRE
 	select ARCH_HAS_SYNC_DMA_FOR_DEVICE if HAS_DMA
 	select ARCH_MIGHT_HAVE_PC_PARPORT if ISA
 	select ARCH_NO_COHERENT_DMA_MMAP if !MMU
-- 
2.20.1

Re: [PATCH] m68k: don't select ARCH_HAS_DMA_PREP_COHERENT for nommu or coldfire

[Geert Uytterhoeven]

Hi Christoph,

On Mon, Jul 8, 2019 at 7:51 PM Christoph Hellwig <hch@lst.de> wrote:
>
> m68k only provides the dma_prep_coherent symbol when an mmu is enabled

arch_dma_prep_coherent

> and not on the coldfire platform.  Fix the Kconfig symbol selection
> up to match this.
>
> Fixes: 69878ef47562 ("m68k: Implement arch_dma_prep_coherent()")

Do you know the SHA1 for the other commit, that causes the issue when
combined with the above?

> Reported-by: Guenter Roeck <linux@roeck-us.net>

Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

> --- a/arch/m68k/Kconfig
> +++ b/arch/m68k/Kconfig
> @@ -5,7 +5,7 @@ config M68K
>         select ARCH_32BIT_OFF_T
>         select ARCH_HAS_BINFMT_FLAT
>         select ARCH_HAS_DMA_MMAP_PGPROT if MMU && !COLDFIRE
> -       select ARCH_HAS_DMA_PREP_COHERENT
> +       select ARCH_HAS_DMA_PREP_COHERENT if HAS_DMA && MMU && !COLDFIRE
>         select ARCH_HAS_SYNC_DMA_FOR_DEVICE if HAS_DMA
>         select ARCH_MIGHT_HAVE_PC_PARPORT if ISA
>         select ARCH_NO_COHERENT_DMA_MMAP if !MMU

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH] m68k: don't select ARCH_HAS_DMA_PREP_COHERENT for nommu or coldfire

[Christoph Hellwig]

On Mon, Jul 08, 2019 at 10:39:48PM +0200, Geert Uytterhoeven wrote:
> Hi Christoph,
> 
> On Mon, Jul 8, 2019 at 7:51 PM Christoph Hellwig <hch@lst.de> wrote:
> >
> > m68k only provides the dma_prep_coherent symbol when an mmu is enabled
> 
> arch_dma_prep_coherent
> 
> > and not on the coldfire platform.  Fix the Kconfig symbol selection
> > up to match this.
> >
> > Fixes: 69878ef47562 ("m68k: Implement arch_dma_prep_coherent()")
> 
> Do you know the SHA1 for the other commit, that causes the issue when
> combined with the above?

I think the culprit is:

commit c30700db9eaabb35e0b123301df35a6846e6b6b4
Author: Christoph Hellwig <hch@lst.de>
Date:   Mon Jun 3 08:43:51 2019 +0200

    dma-direct: provide generic support for uncached kernel segments


Ad it turns out I can't just apply this fix to the dma-mapping tree
because it doesn't have the m68k changes.  So either you'll have to
queue it up, or I'll have to do secondary pull request to fix up
the first one.  Maybe it is eiter if you just send it to Linus
before I send the dma-mapping PR?

Re: [PATCH] m68k: don't select ARCH_HAS_DMA_PREP_COHERENT for nommu or coldfire

[Geert Uytterhoeven]

Hi Christoph,

On Mon, Jul 8, 2019 at 11:23 PM Christoph Hellwig <hch@lst.de> wrote:
> On Mon, Jul 08, 2019 at 10:39:48PM +0200, Geert Uytterhoeven wrote:
> > On Mon, Jul 8, 2019 at 7:51 PM Christoph Hellwig <hch@lst.de> wrote:
> > >
> > > m68k only provides the dma_prep_coherent symbol when an mmu is enabled
> >
> > arch_dma_prep_coherent
> >
> > > and not on the coldfire platform.  Fix the Kconfig symbol selection
> > > up to match this.
> > >
> > > Fixes: 69878ef47562 ("m68k: Implement arch_dma_prep_coherent()")
> >
> > Do you know the SHA1 for the other commit, that causes the issue when
> > combined with the above?
>
> I think the culprit is:
>
> commit c30700db9eaabb35e0b123301df35a6846e6b6b4
> Author: Christoph Hellwig <hch@lst.de>
> Date:   Mon Jun 3 08:43:51 2019 +0200
>
>     dma-direct: provide generic support for uncached kernel segments
>
>
> Ad it turns out I can't just apply this fix to the dma-mapping tree
> because it doesn't have the m68k changes.  So either you'll have to
> queue it up, or I'll have to do secondary pull request to fix up
> the first one.  Maybe it is eiter if you just send it to Linus
> before I send the dma-mapping PR?

OK, will do, after a cycle in next.

I assume you just forgot to add your SoB, and I can add it?

Thanks!

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH] m68k: don't select ARCH_HAS_DMA_PREP_COHERENT for nommu or coldfire

[Christoph Hellwig]

On Tue, Jul 09, 2019 at 09:08:02AM +0200, Geert Uytterhoeven wrote:
> OK, will do, after a cycle in next.

Thanks.  I'll watch your PRs so that I can send the dma-mapping one
right after this.

> I assume you just forgot to add your SoB, and I can add it?

Yes.  And just for the record:

Signed-off-by: Christoph Hellwig <hch@lst.de>