Re: [WARNING: ATTACHMENT UNSCANNED]Re: [linux-next:master 13230/13643] arch/riscv/errata/andes/errata.c:29:23: error: storage size of 'ret' isn't known

[Geert Uytterhoeven <geert@linux-m68k.org>]

Hi Prabhakar,

On Thu, Aug 31, 2023 at 3:02 PM Lad, Prabhakar
<prabhakar.csengg@gmail.com> wrote:
> On Thu, Aug 31, 2023 at 1:01 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> > On Thu, Aug 31, 2023 at 1:54 PM Lad, Prabhakar
> > <prabhakar.csengg@gmail.com> wrote:
> > > On Thu, Aug 31, 2023 at 12:34 PM Conor Dooley
> > > <conor.dooley@microchip.com> wrote:
> > > > On Thu, Aug 31, 2023 at 12:22:50PM +0100, Lad, Prabhakar wrote:
> > > > > On Thu, Aug 31, 2023 at 10:44 AM Conor Dooley
> > > > > <conor.dooley@microchip.com> wrote:
> > > > > >
> > > > > > On Thu, Aug 31, 2023 at 04:52:00PM +0800, kernel test robot wrote:
> > > > > > > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
> > > > > > > head:   a47fc304d2b678db1a5d760a7d644dac9b067752
> > > > > > > commit: f2863f30d1b05e5ecf61c063609cb974954d47f8 [13230/13643] riscv: errata: Add Andes alternative ports
> > > > > > > config: riscv-randconfig-001-20230831 (https://download.01.org/0day-ci/archive/20230831/202308311610.ec6bm2G8-lkp@intel.com/config)
> > > > > > > compiler: riscv64-linux-gcc (GCC) 13.2.0
> > > > > > > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20230831/202308311610.ec6bm2G8-lkp@intel.com/reproduce)
> > > > > > >
> > > > > > > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > > > > > > the same patch/commit), kindly add following tags
> > > > > > > | Reported-by: kernel test robot <lkp@intel.com>
> > > > > > > | Closes: https://lore.kernel.org/oe-kbuild-all/202308311610.ec6bm2G8-lkp@intel.com/
> > > > > > >
> > > > > > > All error/warnings (new ones prefixed by >>):
> > > > > > >
> > > > > > >    arch/riscv/errata/andes/errata.c: In function 'ax45mp_iocp_sw_workaround':
> > > > > > > >> arch/riscv/errata/andes/errata.c:29:23: error: storage size of 'ret' isn't known
> > > > > > >       29 |         struct sbiret ret;
> > > > > > >          |                       ^~~
> > > > > > > >> arch/riscv/errata/andes/errata.c:35:15: error: implicit declaration of function 'sbi_ecall' [-Werror=implicit-function-declaration]
> > > > > > >       35 |         ret = sbi_ecall(ANDESTECH_SBI_EXT_ANDES, ANDES_SBI_EXT_IOCP_SW_WORKAROUND,
> > > > > > >          |               ^~~~~~~~~
> > > > > > > >> arch/riscv/errata/andes/errata.c:29:23: warning: unused variable 'ret' [-Wunused-variable]
> > > > > > >       29 |         struct sbiret ret;
> > > > > > >          |                       ^~~
> > > > > > >    cc1: some warnings being treated as errors
> > > > > > >
> > > > > > >
> > > > > > > vim +29 arch/riscv/errata/andes/errata.c
> > > > > > >
> > > > > > >     26
> > > > > > >     27        static long ax45mp_iocp_sw_workaround(void)
> > > > > > >     28        {
> > > > > > >   > 29                struct sbiret ret;
> > > > > > >     30
> > > > > > >     31                /*
> > > > > > >     32                 * ANDES_SBI_EXT_IOCP_SW_WORKAROUND SBI EXT checks if the IOCP is missing and
> > > > > > >     33                 * cache is controllable only then CMO will be applied to the platform.
> > > > > > >     34                 */
> > > > > > >   > 35                ret = sbi_ecall(ANDESTECH_SBI_EXT_ANDES, ANDES_SBI_EXT_IOCP_SW_WORKAROUND,
> > > > > > >     36                                0, 0, 0, 0, 0, 0);
> > > > > > >     37
> > > > > > >     38                return ret.error ? 0 : ret.value;
> > > > > > >     39        }
> > > > > > >     40
> > > > > >
> > > > > > Looks like the config doesn't enable SBI, so ERRATA_ANDES_CMO will need
> > > > > > to grow a dependency on RISCV_SBI.
> > > > > I think adding dependency for RISCV_SBI on ERRATA_ANDES would be a good idea.
> > > > >
> > > > > While at it I am seeing below warnings with this randconfig:
> > > > > WARNING: unmet direct dependencies detected for ERRATA_ANDES_CMO
> > > > >   Depends on [n]: ERRATA_ANDES [=y] && MMU [=n] && ARCH_R9A07G043 [=y]
> >
> > So the issue is that CONFIG_MMU=n.
> >
> > > --- a/arch/riscv/Kconfig.errata
> > > +++ b/arch/riscv/Kconfig.errata
> > > @@ -3,6 +3,7 @@ menu "CPU errata selection"
> > >  config ERRATA_ANDES
> > >         bool "Andes AX45MP errata"
> > >         depends on RISCV_ALTERNATIVE
> > > +       depends on RISCV_SBI
> > >         help
> > >           All Andes errata Kconfig depend on this Kconfig. Disabling
> > >           this Kconfig will disable all Andes errata. Please say "Y"
> > > @@ -12,7 +13,7 @@ config ERRATA_ANDES
> > >
> > >  config ERRATA_ANDES_CMO
> > >         bool "Apply Andes cache management errata"
> > > -       depends on ERRATA_ANDES && MMU && ARCH_R9A07G043
> >
> > Why does this depend on MMU?
> >
> Currently ARCH_R9A07G043 selects DMA_GLOBAL_POOL and we have
> RISCV_DMA_NONCOHERENT selecting DMA_DIRECT_REMAP which causes below
> build issue when MMU is disabled:
>
> kernel/dma/pool.c: In function 'atomic_pool_expand':
> kernel/dma/pool.c:105:44: error: implicit declaration of function
> 'pgprot_dmacoherent' [-Werror=implicit-function-declaration]
>   105 |
> pgprot_dmacoherent(PAGE_KERNEL),
>       |                                            ^~~~~~~~~~~~~~~~~~
> kernel/dma/pool.c:105:44: error: incompatible type for argument 3 of
> 'dma_common_contiguous_remap'
>   105 |
> pgprot_dmacoherent(PAGE_KERNEL),
>       |
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>       |                                            |
>       |                                            int
> In file included from kernel/dma/pool.c:8:

Hmm, kernel/dma/mapping.c has its use of pgprot_dmacoherent() inside
an #ifdef CONFIG_MMU block.
kernel/dma/pool.c has it inside an #ifdef CONFIG_DMA_DIRECT_REMAP block.

I guess that select should get a dependency on MMU:

    config RISCV_DMA_NONCOHERENT
            select DMA_DIRECT_REMAP if MMU

For comparison, m68k does take that into account:

    select DMA_DIRECT_REMAP if HAS_DMA && MMU && !COLDFIRE

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