linux-kernel - Re: [PATCH] x86: default to reboot via ACPI

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: <Pine.LNX.4.55.0808261406330.28361@cliff.in.clinika.pl>
Date:	Tue, 26 Aug 2008 14:24:20 +0100 (BST)
From:	"Maciej W. Rozycki" <macro@...ux-mips.org>
To:	Avi Kivity <avi@...ranet.com>
cc:	Alan Cox <alan@...rguk.ukuu.org.uk>, Pavel Machek <pavel@...e.cz>,
	Ingo Molnar <mingo@...e.hu>,
	"Eric W. Biederman" <ebiederm@...ssion.com>,
	linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Subject: Re: [PATCH] x86: default to reboot via ACPI

On Tue, 26 Aug 2008, Avi Kivity wrote:

> Most machines are recent machines.

 This is a bold statement I would say.  Any numbers to back it up?

> If a machine doesn't have acpi, this change is safe.
> 
> If a machine has acpi, but doesn't have the reset register set in the 
> FADT, this change is safe.
> 
> If a machine has acpi, and the reset register is set incorrectly, this 
> change is safe.
> 
> If a machine has acpi, and the reset register is wired to the launch 
> controller, then perhaps this change is unsafe.  Don't issue sysrq-b on 
> such machines.

 If a machine has ACPI and it is broken randomly, then the results can be
arbitrary.  Hopefully not destructively.  If even such a simple thing as
wiring the reset line so that it functions correctly can be got wrong,
more so can be more complex matters.

 Failing a better alternative, I suppose the change has to go in though.

  Maciej
--
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/