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Subject: Re: [PATCH 2/2] x86-64: seccomp: fix 32/64 syscall hole
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
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Date: Sun, 01 Mar 2009 08:09:39 +1100
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Cc: linux-mips@linux-mips.org, x86@kernel.org, linux-kernel@vger.kernel.org,
	linuxppc-dev@ozlabs.org, sparclinux@vger.kernel.org,
	Andrew Morton <akpm@linux-foundation.org>, stable@kernel.org,
	Roland McGrath <roland@redhat.com>
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On Sat, 2009-02-28 at 09:23 -0800, Linus Torvalds wrote:
> 
> On Fri, 27 Feb 2009, Roland McGrath wrote:
> > 
> > I don't know any other arch well enough to be sure that TIF_32BIT isn't the
> > wrong test there too.  I'd like to leave that worry to the arch maintainers.
> 
> Agreed - it may be that others will want to not use TIF_32BIT too. It 
> really does make much more sense to have it as a thread-local status flag 
> than as an atomic (and thus expensive to modify) thread-flag, not just on 
> x86.

FYI. _TIF_32BIT is the right test on powerpc (it's also what entry_64.S
tests to pick the appropriate syscall table).

Cheers,
Ben.