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Message-ID: <475DE37F.20706@davidnewall.com>
Date: Tue, 11 Dec 2007 11:40:23 +1030
From: David Newall <david@davidnewall.com>
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To: Krzysztof Halasa <khc@pm.waw.pl>
CC: Rene Herman <rene.herman@keyaccess.nl>, Pavel Machek <pavel@ucw.cz>,
       Andi Kleen <andi@firstfloor.org>, Alan Cox <alan@lxorguk.ukuu.org.uk>,
       "David P. Reed" <dpreed@reed.com>, linux-kernel@vger.kernel.org,
       Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
       "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: RFC: outb 0x80 in inb_p, outb_p harmful on some modern AMD64
 with MCP51 laptops
References: <475879CD.9080006@reed.com> <p733auekcly.fsf@bingen.suse.de>	<20071207160439.71b7f46a@the-village.bc.nu>	<20071209125458.GB4381@ucw.cz>	<20071209165908.GA15910@one.firstfloor.org>	<20071209212513.GC24284@elf.ucw.cz> <475CBDD7.5050602@keyaccess.nl> <m3bq8y23de.fsf@maximus.localdomain>
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Where did the 8us delay come from?  The documentation and source is 
careful not to say how long the delay is.  Would changing it to, say 
1us, be technically wrong?  Is code that requires 8us correct?