From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from list by lists.gnu.org with archive (Exim 4.71) id 1ehfQs-0002f0-9G for mharc-grub-devel@gnu.org; Fri, 02 Feb 2018 12:47:26 -0500 Received: from eggs.gnu.org ([208.118.235.92]:39227) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ehfPm-0001kF-R3 for grub-devel@gnu.org; Fri, 02 Feb 2018 12:47:24 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ehfOi-0004Vb-QK for grub-devel@gnu.org; Fri, 02 Feb 2018 12:46:18 -0500 Received: from mout.gmx.net ([212.227.17.20]:42917) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1ehfOi-0004Rk-0z for grub-devel@gnu.org; Fri, 02 Feb 2018 12:45:12 -0500 Received: from scdbackup.webframe.org ([79.222.38.208]) by mail.gmx.com (mrgmx101 [212.227.17.168]) with ESMTPSA (Nemesis) id 0MIzGn-1ejzUm1NZx-002XMx; Fri, 02 Feb 2018 09:16:41 +0100 Date: Fri, 02 Feb 2018 09:15:42 +0100 From: "Thomas Schmitt" To: grub-devel@gnu.org Subject: Re: A thread on grub-bug could need attention Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Cc: michel@bouissou.net References: <4cc95338-8da7-e953-ff55-175b554771b8@bouissou.net> In-Reply-To: <4cc95338-8da7-e953-ff55-175b554771b8@bouissou.net> Message-Id: <28716785462546254838@scdbackup.webframe.org> X-Provags-ID: V03:K0:3wQryHjx8LL2I7ORGStkvgFchT3/ciQCmeL00KZr2WX2HS74kVG OP+cgKyCiqNiMsZkNvJY62Myt0aR7vVsiJz0vyb3uxwsykSNoTjLIByY6CI3xKuDUnwwodU b35pB93S2HaLuapSzxN4Ri8DgpErklvPvjd0/BRisG3PzFy93gF4JCenRF0qyaPfkNKMqph 7zvCijImfT7VoskxXLBzg== X-UI-Out-Filterresults: notjunk:1;V01:K0:Yq1UUAHYOBU=:9U+7YCM8+Wppymh/u36OY/ jiejj+tuNaYp1yjgSXs2jQ2dz2xOBkO7+0j4g03OHQdNFfdFROyjmGnVZ/OlwCFQziDEXWDET H1USks9lAbj2d6x1hBWToSv/vcMAd8Qpw5gHkixgWZsdEtEnpK5qggU+OaoH1OtuJlqXtBLA2 Gt2xpLwYYLQ++mzMjtEjwS1PMXs68ttYJqdXZl6mmnIHrNS7VrlQGM3Bn66XYQtxw6avndMbt 4hu0N8/35QuN4ii+QfntQVirn8FpJ7Cx9y9jXoSX3M1naRAuerX1QMhUgKKYppMYTRkR839WS drzSy/Kl3VfyOGDiEpPdlWdE5yi1bEYg1D7dFSfAmdgdb+PEGT1J2jhFbxX5iUTDqvgqaHknH 3x8h0po/Bnc+DPSvKwYOs4ES1V2/t4lEkf9aKyRgwXOOvqXP1SVcqbXIo8C2fNNsZJiq1+KLC +Lypf5QZxGcvcdVKp1JJefhXvZy7cie7Z/hOWKP73/dDiit6me46dApvBy6rhrzSdM8D+AgM1 4+fMf8AhrjPbBtHN6xk1pLV6VT/rLsHhfZXQaWAI1yZ2+9C8iqDylMPbabxKj776o2oVDR+vT WrOEct9176o6yGBssQ0Hy16mYEdW9+WIeDl8rE9eCF6FFElKmzWkPRPjufdATeXBG5sO6ZE4b STFCEruxi65dJhNuazPVVEogGj37hbQ2mGH2SJvSjLyD/Z6Y/tJ09iXfbbMO/TRAn98fDg+Lg vMs+NkiHjASZsRcoGfR9Tl0LfyQHWB2MddL5tZoe3wR7hRPLYcOHtkNJZ10ku/ZZc6SAiOgDH Em42RPW7PGXJoAJMN5FJECEpznm7m5RcbB7Yl9S6oQIv6arTC0= X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 212.227.17.20 X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: The development of GNU GRUB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 02 Feb 2018 17:47:25 -0000 Hi, i wrote: > > zeroize 512-byte block 1 of the > > Debian Live ISO and then try to boot it from USB stick Michel Bouissou wrote: > I made it (with latest debian-gnome 9.3 live),i Now we have no surplus GPT any more. The EFI system partition is only marked by the MBR partition 2 (and by the El Torito catalog which should be ignored when found on USB stick). > and tested it OK on *another* machine. > But on the machine where the problem is, it does *NOT* boot. Normally i would now again exclude the theory that the partitions inside the ISO are to blame. (We still have to explain why the GRUB installations on hard-disk-like partitioned USB sticks failed too.) > It does display the key brand/model (instead of "Windows boot manager") But this slight change in firmware behavior could be significant. Under the theory that it's the partition layout and not the EFI partition image content or its way to hop on the ISO, there remains the nested partition situation as main suspect: $ /sbin/fdisk -l debian-live-9.3.0-amd64-xfce.iso ... Device Boot Start End Sectors Size Id Type debian-live-9.3.0-amd64-xfce.iso1 * 0 3803903 3803904 1.8G 0 Empty debian-live-9.3.0-amd64-xfce.iso2 1548 2379 832 416K ef EFI The block range of partition 2 is inside partition 1. Normally the type 0 ("Empty") of partition 1 is enough to let firmwares tolerate this. Partition 1 is not needed for the boot process. It just protects the ISO from partition editors and provides a mountable partition to operating systems. So the next experiment would be to remove it, i.e. zeroize its slot in the MBR. One can do it in the ISO file img=debian-live-9.3.0-amd64-xfce.iso or directly on the USB stick where it was copied img=/dev/sdc Either by: /sbin/fdisk "$img" <<+ d 1 w + Or by: dd if=/dev/zero bs=1 seek=446 count=16 conv=notrunc of="$img" The result should then be $ /sbin/fdisk -l "$img" ... Device Boot Start End Sectors Size Id Type debian-live-9.3.0-amd64-xfce.iso2 1548 2379 832 416K ef EFI Have a nice day :) Thomas