linux-kernel - Re: [PATCH 01/18] powerpc: Add ability to build little endian kernels

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 1 Oct 2010 07:40:49 -0400
From:	Josh Boyer <jwboyer@...il.com>
To:	Ian Munsie <imunsie@....ibm.com>
Cc:	linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
	benh@...nel.crashing.org, Michal Marek <mmarek@...e.cz>,
	Albert Herranz <albert_herranz@...oo.es>, paulus@...ba.org,
	Andreas Schwab <schwab@...ux-m68k.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Sam Ravnborg <sam@...nborg.org>,
	Torez Smith <lnxtorez@...ux.vnet.ibm.com>
Subject: Re: [PATCH 01/18] powerpc: Add ability to build little endian kernels

On Fri, Oct 1, 2010 at 3:05 AM, Ian Munsie <imunsie@....ibm.com> wrote:
> diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
> index d361f81..074ff12 100644
> --- a/arch/powerpc/platforms/Kconfig.cputype
> +++ b/arch/powerpc/platforms/Kconfig.cputype
> @@ -329,3 +329,19 @@ config CHECK_CACHE_COHERENCY
>        bool
>
>  endmenu
> +
> +config ARCH_SUPPORTS_LITTLE_ENDIAN
> +       bool
> +
> +config CPU_LITTLE_ENDIAN
> +       bool "Build little endian kernel"
> +       depends on ARCH_SUPPORTS_LITTLE_ENDIAN && EXPERIMENTAL
> +       default n
> +       help
> +         This option selects whether a big endian or little endian kernel will
> +         be built.
> +
> +         Note that if building a little endian kernel, CROSS_COMPILE must
> +         point to a toolchain capable of targetting little endian powerpc,
> +         while the toolchain specified by CROSS32_COMPILE must be capable of
> +         targetting *BIG* endian PowerPC.

Have you tested this support with a userspace containing floating
point instructions?  I wonder if CONFIG_MATH_EMULATION is going to
need work at all, and if the boards with an actual FPU (440EP, 440EPx,
460EX, etc) would have issues.

josh
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/