Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757254AbYHRWDU (ORCPT ); Mon, 18 Aug 2008 18:03:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753618AbYHRWDA (ORCPT ); Mon, 18 Aug 2008 18:03:00 -0400 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:52995 "EHLO gprs189-60.eurotel.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753074AbYHRWC7 (ORCPT ); Mon, 18 Aug 2008 18:02:59 -0400 Date: Tue, 19 Aug 2008 00:04:19 +0200 From: Pavel Machek To: David Fries Cc: "Maciej W. Rozycki" , Ingo Molnar , linux-kernel@vger.kernel.org, "H. Peter Anvin" , Thomas Gleixner , "Rafael J. Wysocki" Subject: Re: [PATCH] Fix i486 suspend to disk CR4 oops Message-ID: <20080818220419.GB2053@elf.ucw.cz> References: <20080818040340.GB17528@spacedout.fries.net> <20080818125803.GC17528@spacedout.fries.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080818125803.GC17528@spacedout.fries.net> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1516 Lines: 34 On Mon 2008-08-18 07:58:03, David Fries wrote: > On Mon, Aug 18, 2008 at 05:14:50AM +0100, Maciej W. Rozycki wrote: > > On Sun, 17 Aug 2008, David Fries wrote: > > > + /* cr4 was introduced in the Pentium CPU */ > > > > NACK. Later i486 chips do have CR4 -- for PSE, VME, etc. (the set of > > features varies across the line). Use a fixup as elsewhere or something. > > That's what I get for reading the Intel instruction set reference, > "The CR4 register was added to the Intel Architecture beginning with > the Pentium processor." > > Ingo Molnar, thanks, I'll try the read_cr4_safe() version tonight (the > computer is in the trunk of my car and I'm about ready to head to > work). > > In light of the above, how about updating the comments > - /* cr4 was introduced in the Pentium CPU */ > - jecxz 1f # cr4 Pentium and higher, skip if zero > + /* cr4 not in i386 only some i486, skip if zero */ > + jecxz 1f # cr4 not in i386 only some i486, skip if zero Okay, can it happen that that cr4 is zero legitimately? If newer 486SX chips support cr4 but not coprocessor...? Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/