linux-kernel - Re: [PATCH] x86_64: fix problems due to use of "outb" to port 80 on some AMD64x2 laptops, etc.

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: <4766C602.5050409@keyaccess.nl>
Date:	Mon, 17 Dec 2007 19:54:58 +0100
From:	Rene Herman <rene.herman@...il.com>
To:	"linux-os (Dick Johnson)" <linux-os@...logic.com>
CC:	"David P. Reed" <dpreed@...d.com>, Avi Kivity <avi@...ranet.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Linux kernel <linux-kernel@...r.kernel.org>,
	Ingo Molnar <mingo@...hat.com>,
	"H. Peter Anvin" <hpa@...or.com>, Pavel Machek <pavel@....cz>,
	kvm-devel <kvm-devel@...ts.sourceforge.net>
Subject: Re: [PATCH] x86_64: fix problems due to use of "outb" to port 80
 on some AMD64x2 laptops, etc.

On 17-12-07 19:14, linux-os (Dick Johnson) wrote:

> Attached is a patch that changes the outs to ins on port 0x80.

No, that isn't useful. Only a write is "guaranteed" to make ISA/LPC meaning 
the timing for a read varies wildly. See the in/out cycles results posted 
earlier. Was also reading the Intel PIIX(3) chiset datasheet today which 
specifically mentions that only writes flow through to ISA, reads do not.

Rene.
--
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/