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Date: Fri, 1 Nov 2002 01:23:24 +0000
From: Jamie Lokier <lk@tantalophile.demon.co.uk>
To: Linus Torvalds <torvalds@transmeta.com>,
       Linux-Kernel ML <linux-kernel@vger.kernel.org>,
       Ingo Molnar <mingo@elte.hu>
Subject: Re: [PATCH] Clear TLS on execve
Message-ID: <20021101012324.GB30865@bjl1.asuk.net>
References: <20021031143439.GA1697@home.ldb.ods.org>
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Luca Barbieri wrote:
> This trivial patch causes the TLS to be cleared on execve (code is
> in flush_thread).  This is necessary to avoid ESRCH errors when
> set_thread_area is asked to choose a free TLS entry after several
> nested execve's.

Ouch!

> The LDT also has a similar problem, but it is less serious because the
> LDT code doesn't scan for free entries. I'll probably send a patch to
> fix this too, unless there is something important relying on this behavior.

Ouch again!  Does the LDT really not get released on execve?  I am
using threading code which _does_ scan for free entries in the LDT -
using the lar instruction.  I'd never stumbled across this, though.
I'll be glad of your patch.

-- Jamie
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