Re: [PATCH] powerpc: fix the allyesconfig build

[Geert Uytterhoeven]

Hi Stephen,

On Sat, Nov 28, 2020 at 2:28 AM Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> wrote:
> There are 2 drivers that have arrays of packed structures that contain
> pointers that end up at unaligned offsets.  These produce warnings in
> the PowerPC allyesconfig build like this:
>
> WARNING: 148 bad relocations
> c00000000e56510b R_PPC64_UADDR64   .rodata+0x0000000001c72378
> c00000000e565126 R_PPC64_UADDR64   .rodata+0x0000000001c723c0
>
> They are not drivers that are used on PowerPC (I assume), so mark them
> to not be built on PPC64 when CONFIG_RELOCATABLE is enabled.
>
> Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> Cc: Michael Turquette <mturquette@xxxxxxxxxxxx>
> Cc: Stephen Boyd <sboyd@xxxxxxxxxx>
> Cc: Yisen Zhuang <yisen.zhuang@xxxxxxxxxx>
> Cc: Salil Mehta <salil.mehta@xxxxxxxxxx>
> Cc: David S. Miller <davem@xxxxxxxxxxxxx>
> Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
> Cc: Nicholas Piggin  <npiggin@xxxxxxxxx>
> Cc: Daniel Axtens <dja@xxxxxxxxxx>
> Cc: Joel Stanley <joel@xxxxxxxxx>
> Signed-off-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>

Thanks for your patch!

> --- a/drivers/clk/renesas/Kconfig
> +++ b/drivers/clk/renesas/Kconfig
> @@ -151,6 +151,10 @@ config CLK_R8A779A0
>         select CLK_RENESAS_CPG_MSSR
>
>  config CLK_R9A06G032
> +       # PPC64 RELOCATABLE kernels cannot handle relocations to
> +       # unaligned locations that are produced by the array of
> +       # packed structures in this driver.
> +       depends on !(PPC64 && RELOCATABLE)
>         bool "Renesas R9A06G032 clock driver"
>         help
>           This is a driver for R9A06G032 clocks

I prefer to fix this in the driver instead.  The space saving by packing the
structure is minimal.
I've sent a patch
https://lore.kernel.org/r/20201130085743.1656317-1-geert+renesas@xxxxxxxxx
(when lore is back)

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

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