Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757349AbXEIOa2 (ORCPT ); Wed, 9 May 2007 10:30:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754908AbXEIOaU (ORCPT ); Wed, 9 May 2007 10:30:20 -0400 Received: from caffeine.uwaterloo.ca ([129.97.134.17]:34137 "EHLO caffeine.csclub.uwaterloo.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754869AbXEIOaT (ORCPT ); Wed, 9 May 2007 10:30:19 -0400 Date: Wed, 9 May 2007 10:30:18 -0400 To: "Antonino A. Daplas" Cc: Alexander van Heukelum , Andrew Morton , Andi Kleen , "H. Peter Anvin" , lkml Subject: Re: [PATCH] Make bootsector stub 16-bit-only (i386) Message-ID: <20070509143018.GH8753@csclub.uwaterloo.ca> References: <20070505104452.GA30944@mailshack.com> <20070508032817.e4734798.akpm@linux-foundation.org> <20070508183232.GA13225@mailshack.com> <1178669047.4747.15.camel@daplas> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1178669047.4747.15.camel@daplas> User-Agent: Mutt/1.5.13 (2006-08-11) From: lsorense@csclub.uwaterloo.ca (Lennart Sorensen) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4175 Lines: 113 On Wed, May 09, 2007 at 08:04:07AM +0800, Antonino A. Daplas wrote: > On Tue, 2007-05-08 at 20:32 +0200, Alexander van Heukelum wrote: > > On Tue, May 08, 2007 at 03:28:17AM -0700, Andrew Morton wrote: > > > On Sat, 5 May 2007 12:44:52 +0200 Alexander van Heukelum wrote: > > > > --- a/arch/i386/boot/bootsect.S > > > > +++ b/arch/i386/boot/bootsect.S > > > > @@ -44,7 +44,7 @@ #endif > > > > _start: > > > > > > > > # Normalize the start address > > > > - jmpl $BOOTSEG, $start2 > > > > + jmpw $BOOTSEG, $start2 > > > > > > Sigh, another blow struck in the ongoing struggle between my Vaio and the > > > rest of the world. > > > > > > Stone-cold black-screen lockup immediately upon boot. > > > > > > Stock FC5 install, config at > > > http://userweb.kernel.org/~akpm/config-sony.txt > > > > Sigh... sounds impossible. > > > > I assume this is repeatable? And this patch changes behaviour? What do > > you mean by immediate? Before or after decompression? > > > > Fishy... As Andi and Peter have mentioned, this code is not executed. > > There is only one user of the same memory area this early... video.S > > uses it to store some collected data, but as far as I can see only the > > 'CONFIG_VIDEO_RETAIN' code also reads it back. If it happens before > > decompression, could you see if changing > > #define CONFIG_VIDEO_RETAIN -> #undef CONFIG_VIDEO_RETAIN > > in arch/i386/boot/video.S changes anything? > > > > Do you select a non-standard textmode? Does vga=ask show up? > > > > *looks around some* > > > > Oh! A padding hole in a struct! That could be a problem. If the freeze > > is after decompression, could you test if this makes it work again? > > > > Greetings, > > Alexander > > > > --- > > > > Commit 89ec4c238e7a3d7e660291f3f1a8181381baad77 introduced a discrepancy > > between the struct screen_info which is used by the C code, and the > > PARAM_* offsets which are used in the real-mode kernel. This is an > > attempt to rectify the situation, but I have no way to test it. > > > > Signed-off-by: Alexander van Heukelum > > > > --- > > > > diff --git a/arch/i386/boot/bootsect.S b/arch/i386/boot/bootsect.S > > diff --git a/arch/i386/boot/video.S b/arch/i386/boot/video.S > > index 8143c95..8e404cb 100644 > > --- a/arch/i386/boot/video.S > > +++ b/arch/i386/boot/video.S > > @@ -95,7 +95,8 @@ #define PARAM_VESAPM_SEG 0x2e > > #define PARAM_VESAPM_OFF 0x30 > > #define PARAM_LFB_PAGES 0x32 > > #define PARAM_VESA_ATTRIB 0x34 > > -#define PARAM_CAPABILITIES 0x36 > > +#define PARAM_VESA_PAD 0x36 > > +#define PARAM_CAPABILITIES 0x38 Isn't this ^^^ what you are suggesting below? > > /* Define DO_STORE according to CONFIG_VIDEO_RETAIN */ > > #ifdef CONFIG_VIDEO_RETAIN > > diff --git a/include/linux/screen_info.h b/include/linux/screen_info.h > > index b02308e..0a2e892 100644 > > --- a/include/linux/screen_info.h > > +++ b/include/linux/screen_info.h > > @@ -41,8 +41,8 @@ struct screen_info { > > u16 vesapm_off; /* 0x30 */ > > u16 pages; /* 0x32 */ > > u16 vesa_attributes; /* 0x34 */ > > - u32 capabilities; /* 0x36 */ > > - /* 0x3a -- 0x3b reserved for future expansion */ > > + u16 vesa_pad; /* 0x36 */ > > + u32 capabilities; /* 0x38 */ > > /* 0x3c -- 0x3f micro stack for relocatable kernels */ > > }; > > > > You would also need this minor change. > > Tony > > diff --git a/arch/i386/boot/video.S b/arch/i386/boot/video.S > index 5e2280c..2d637d1 100644 > --- a/arch/i386/boot/video.S > +++ b/arch/i386/boot/video.S > @@ -95,7 +95,7 @@ #define PARAM_VESAPM_SEG 0x2e > #define PARAM_VESAPM_OFF 0x30 > #define PARAM_LFB_PAGES 0x32 > #define PARAM_VESA_ATTRIB 0x34 > -#define PARAM_CAPABILITIES 0x36 > +#define PARAM_CAPABILITIES 0x38 > > /* Define DO_STORE according to CONFIG_VIDEO_RETAIN */ > #ifdef CONFIG_VIDEO_RETAIN -- Len Sorensen - 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/