Date: Tue, 16 Nov 2004 00:02:49 +0100
From: David Weinehall <tao@acc.umu.se>
To: Nickolai Zeldovich <kolya@MIT.EDU>
Cc: linux-kernel@vger.kernel.org, csapuntz@stanford.edu
Subject: Re: [patch] Fix GDT re-load on ACPI resume
Message-ID: <20041115230249.GR29980@khan.acc.umu.se>
Mail-Followup-To: Nickolai Zeldovich <kolya@MIT.EDU>,
	linux-kernel@vger.kernel.org, csapuntz@stanford.edu
References: <Pine.GSO.4.58L.0411151525540.28749@contents-vnder-pressvre.mit.edu>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <Pine.GSO.4.58L.0411151525540.28749@contents-vnder-pressvre.mit.edu>
User-Agent: Mutt/1.4.1i
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1278
Lines: 27

On Mon, Nov 15, 2004 at 03:35:14PM -0500, Nickolai Zeldovich wrote:
> The ACPI resume code currently uses a real-mode 16-bit lgdt instruction to
> reload the GDT.  This only restores the lower 24 bits of the GDT base
> address.  In recent kernels, the GDT seems to have moved out of the lower
> 16 megs, thereby causing the ACPI resume to fail -- an invalid GDT was
> being loaded.
> 
> This simple patch adds the 0x66 prefix to lgdt, which forces it to load
> all 32 bits of the GDT base address, thereby removing any restrictions on
> where the GDT can be placed in memory.  This makes ACPI resume work for me
> on a Thinkpad T40 laptop.

Sadly doesn't work for me.  ACPI resume broke for me with
2.6.10-rc1-bk15 (possibly 14, but that one didn't compile), and this
patch does not fix it.


Regards: David Weinehall
-- 
 /) David Weinehall <tao@acc.umu.se> /) Northern lights wander      (\
//  Maintainer of the v2.0 kernel   //  Dance across the winter sky //
\)  http://www.acc.umu.se/~tao/    (/   Full colour fire           (/
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/