From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrey Borzenkov Subject: Re: Attempt rebooting via port CF9 if it seems to be available Date: Wed, 12 Nov 2008 21:49:10 +0300 Message-ID: <200811122149.11947.arvidjaar@mail.ru> References: <007e7d616a5d1c2e16ad627d03f8b97799445e71.1226032943.git.len.brown@intel.com> <491A225F.4090407@zytor.com> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart24054807.FlmPopGCp2"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Return-path: Received: from mx71.mail.ru ([194.67.23.4]:63941 "EHLO mx71.mail.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752385AbYKLStR (ORCPT ); Wed, 12 Nov 2008 13:49:17 -0500 In-Reply-To: <491A225F.4090407@zytor.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "H. Peter Anvin" Cc: Len Brown , Matthew Garrett , Ingo Molnar , Avi Kivity , linux-acpi@vger.kernel.org, Len Brown , Eduardo Habkost , Andrew Morton , Linux Kernel Mailing List --nextPart24054807.FlmPopGCp2 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline On Wednesday 12 November 2008, H. Peter Anvin wrote: > Looking at doing the port CF9 fallback, I stumbled onto something fishy. >=20 > I wonder if anyone here happens to have any idea why we turn off > caching in machine_real_restart()? Jumping to the BIOS is *not* a > reset; we jump to the decompressed BIOS on low memory which is usually > shadowed, not to the BIOS entry point. In that way, it's more of an > INIT than a reset, and disabling caching seems broken. >=20 > Either way, here is a preliminary patch to do the CF9 if safe, and then > falling back to keyboard reboot. I'm a bit concerned about how to test > it, of course; this stuff is sensitive and just about impossible to test > except on millions of machines at once... >=20 > If you have any machines (especially problematic ones) and find that > this patch either helps or hurts or do nothing, please do let me know so > I have any idea of the extent of coverage. >=20 Works here both with default and reboot=3Dp. --nextPart24054807.FlmPopGCp2 Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEABECAAYFAkkbJScACgkQR6LMutpd94zQJACcDbLLCdaEG44dUWiOLHkJPxxC XgIAoMIcqwL+jqCCrensZkqKHP1rNyQy =xmel -----END PGP SIGNATURE----- --nextPart24054807.FlmPopGCp2--