Re: [PATCH] powerpc: fix the allyesconfig build

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Michael Ellerman <mpe@ellerman.id.au>,
	PowerPC <linuxppc-dev@lists.ozlabs.org>,
	Nicholas Piggin <npiggin@gmail.com>,
	Daniel Axtens <dja@axtens.net>, Joel Stanley <joel@jms.id.au>,
	Geert Uytterhoeven <geert+renesas@glider.be>,
	Michael Turquette <mturquette@baylibre.com>,
	Stephen Boyd <sboyd@kernel.org>,
	Yisen Zhuang <yisen.zhuang@huawei.com>,
	Salil Mehta <salil.mehta@huawei.com>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
	linux-clk <linux-clk@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	netdev <netdev@vger.kernel.org>
Subject: Re: [PATCH] powerpc: fix the allyesconfig build
Date: Mon, 30 Nov 2020 09:58:23 +0100	[thread overview]
Message-ID: <CAMuHMdVJKarCRRRJq_hmvvv0NcSpREdqDbH8L5NitZmFUEbqmw@mail.gmail.com> (raw)
In-Reply-To: <20201128122819.32187696@canb.auug.org.au>

Hi Stephen,

On Sat, Nov 28, 2020 at 2:28 AM Stephen Rothwell <sfr@canb.auug.org.au> 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@glider.be>
> Cc: Michael Turquette <mturquette@baylibre.com>
> Cc: Stephen Boyd <sboyd@kernel.org>
> Cc: Yisen Zhuang <yisen.zhuang@huawei.com>
> Cc: Salil Mehta <salil.mehta@huawei.com>
> Cc: David S. Miller <davem@davemloft.net>
> Cc: Jakub Kicinski <kuba@kernel.org>
> Cc: Nicholas Piggin  <npiggin@gmail.com>
> Cc: Daniel Axtens <dja@axtens.net>
> Cc: Joel Stanley <joel@jms.id.au>
> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

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@glider.be
(when lore is back)

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