From mboxrd@z Thu Jan 1 00:00:00 1970 From: "pelzflorian (Florian Pelz)" Subject: Re: ISO installer image: GPT versus MBR partitions Date: Tue, 23 Apr 2019 23:43:40 +0200 Message-ID: <20190423214340.tfck3m4gaxtnweog@pelzflorian.localdomain> References: <20190423195030.czrsu4eut5a37xsx@pelzflorian.localdomain> <30584672815166188411@scdbackup.webframe.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Return-path: Received: from eggs.gnu.org ([209.51.188.92]:33555) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hJ3Ch-00042L-GQ for guix-devel@gnu.org; Tue, 23 Apr 2019 17:43:52 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hJ3Cf-000550-W3 for guix-devel@gnu.org; Tue, 23 Apr 2019 17:43:51 -0400 Content-Disposition: inline In-Reply-To: <30584672815166188411@scdbackup.webframe.org> List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org Sender: "Guix-devel" To: Thomas Schmitt Cc: bug-xorriso@gnu.org, guix-devel@gnu.org On Tue, Apr 23, 2019 at 10:18:10PM +0200, Thomas Schmitt wrote: > Florian Pelz wrote: > > florian@florianmacbook ~ [env]$ grub-mkrescue -o output.iso minimal > > --xorriso=3D./grub-mkrescue-sed.sh > > grub-mkrescue: warning: Your xorriso doesn't support `--grub2-boot-in= fo'. > > Some features are disabled. Please use xorriso 1.2.9 or later.. > > > > and yields no output.iso for me. Note that xorriso actually has > > version 1.5.0. >=20 > Does the script offer x-permission ? > (Shame on me for not thinking of this in my download instructions.) >=20 This was the error. It works after `chmod +x grub-mkrescue-sed.sh`. On Tue, Apr 23, 2019 at 08:14:48PM +0200, Thomas Schmitt wrote: > It would be interesting to learn about EFIs which fail without MBR > signature. > [=E2=80=A6] > - Put the resulting output.iso on USB stick and offer it to your firmwa= re > at boot time. > Is it not found by the EFI boot manager ? > If you let it boot, does the machine not show a GRUB prompt in the en= d ? >=20 It shows up twice in the boot selection screen as =E2=80=9CGRUB 2.02=E2=80= =9D and =E2=80=9CEFI Boot=E2=80=9D just like the Guix USB drive before. It is bootable and sh= ows a GRUB prompt on my Macbook. > - Negative results with other mode settings in MKRESCUE_SED_MODE would = be > interesting, too. >=20 I can try tomorrow. By the way, someone I know has a most peculiar machine called Lenovo Ideapad 100S which does not boot Guix, but apparently is very picky in general (cf. ). Its CPU is claimed to support 64-bit, but its boot firmware rejects most 64-bit isos. I wonder if we could get that machine to boot Guix (at least it currently cannot boot guixsd-install-0.15.0.i686-linux.iso), but that may well be a waste of time. It might just not be feasible to please every EFI system. > I wrote: > > > So programs like /sbin/isosize can tell the image size even when th= e > > > ISO has already been copied to USB stick. >=20 > > Sounds like this could be used to get a checksum or maybe GPG > > verification of a USB drive that supposedly contains the iso. >=20 > That's what this property is advised for in Debian's CD FAQ. > One can read trailing garbage not only from USB sticks but also from > most DVD types. > (The layout with nested partitions obsoletes the cleanliness > considerations about partition start at LBA 0.) > So=E2=80=A6 GPT is wrong for some optical media too? Regards, Florian