linux-kernel - Re: Remove execution domain support

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:	Mon, 13 Apr 2015 18:21:41 -0700
From:	Andy Lutomirski <luto@...nel.org>
To:	Richard Weinberger <richard@....at>, linux-arch@...r.kernel.org
CC:	linux-kernel@...r.kernel.org, rth@...ddle.net,
	ink@...assic.park.msu.ru, mattst88@...il.com, vgupta@...opsys.com,
	linux@....linux.org.uk, catalin.marinas@....com,
	will.deacon@....com, hskinnemoen@...il.com, egtvedt@...fundet.no,
	realmz6@...il.com, msalter@...hat.com, a-jacquiot@...com,
	starvik@...s.com, jesper.nilsson@...s.com, dhowells@...hat.com,
	rkuo@...eaurora.org, tony.luck@...el.com, fenghua.yu@...el.com,
	geert@...ux-m68k.org, james.hogan@...tec.com, monstr@...str.eu,
	ralf@...ux-mips.org, yasutake.koichi@...panasonic.com,
	lftan@...era.com, jonas@...thpole.se, jejb@...isc-linux.org,
	deller@....de, benh@...nel.crashing.org, paulus@...ba.org,
	mpe@...erman.id.au, schwidefsky@...ibm.com,
	heiko.carstens@...ibm.com, liqin.linux@...il.com,
	lennox.wu@...il.com, davem@...emloft.net, cmetcalf@...hip.com,
	jdike@...toit.com, akpm@...ux-foundation.org, oleg@...hat.com,
	hch@inf
Subject: Re: Remove execution domain support

On 04/11/2015 01:47 PM, Richard Weinberger wrote:
> A long time ago there was the idea to support different ABIs on Linux
> Such that someone could use for example SCO UNIX binaries on Linux
> without emulation. While the linux-abi project existed mostly as
> out-of-tree patch it's core component, execution domains,
> went mainline. An execution domain allows to specify mappings between
> different ABIs, these mappings consist of signal, error, socket type,
> socket options and addess familiy mappings.
> Mainline has only support for signal mappings.
> The signal mapping happens in the architecutre specific signal code.
> Some archs support it, some not, most of them copy&pasted from i386.
>
> While the mapping support is incomplete we have two in-kernel users of
> execution domains.
>
> 1. RISC OS personality on ARM.
> The Kconfig help message states that this feature is very experimental
> and it is likely that it never worked as expected.
> Russel is fine with the removal.
>
> 2. ia32 support on ia64.
> This is a left over from:
> commit 32974ad4907cdde6c9de612cd1b2ee0568fb9409 ([IA64] Remove COMPAT_IA32 support)
> It registers a dummy Linux/x86 execdomain to make calls to
> personality(PER_LINUX32) faster as the execution domain core code
> would try to load a module.
>
> As both users can be removed there is no user left and we can remove
> execution domains support at all from the kernel.
> The removal will make architecutre specific signal handling easier
> and there is no need to keep execuction domains as this feature is
> obviously incomplete and abandoned.

I like this.

FWIW, we recently removed restart_block from thread_info, so I'm not too 
worried about fallout from removing another field.

--Andy
--
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/