linux-kernel - Re: [PATCH] x86: Add reboot quirk for Dell Precision M4600

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]

Message-ID: <20110806153003.GA1238@srcf.ucam.org>
Date:	Sat, 6 Aug 2011 16:30:03 +0100
From:	Matthew Garrett <mjg59@...f.ucam.org>
To:	Ingo Molnar <mingo@...e.hu>
Cc:	Mel Gorman <mgorman@...e.de>, tglx@...utronix.de, hpa@...or.com,
	bruno@...a-net.ch, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] x86: Add reboot quirk for Dell Precision M4600

On Sat, Aug 06, 2011 at 08:56:35AM +0200, Ingo Molnar wrote:
> Weird - ACPI is the default Windows method of reboot - how come it 
> does not work on that box? Does Windows work around this specific 
> machine (unlikely), or is our ACPI boot sequence not 100% compatible 
> with the Windows method (more likely IMO)?

The ACPI reboot method on these machines hits the keyboard controller 
rather than PCI, which is unusual. What I suspect is that the write 
triggers some SMM or EC code that's making assumptions about system 
state, and we're not quite identical. Bouncing on the keyboard 
controller from userspace with init=/bin/bash wedges in the same way.

-- 
Matthew Garrett | mjg59@...f.ucam.org
--
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/