Thomas Schmitt wrote: > Hi, > > the fresh development upload of xorriso-0.5.5 > with timestamp 2010.04.22.160615 implements the > wish about --efi-boot : > > I've tested xorriso version : 0.5.5 Version timestamp : 2010.04.22.221241 and it worked fine.
> Vladimir Serbinenko wrote 17 Apr 2010: > >> I would like to have efi+bios cd with 2 eltorito >> entries: one with platformid=0 and another one with platformid=0xef. >> [...] >> I would like that on hybrid BIOS always come in >> default entry to avoid hitting BIOS bugs >> In case of just EFI the Section header entry and Section entry become >> Validation entry and default entry. >> > > So now xorriso -as mkisofs has this provisory > behavior: > > -b is for 80x86 BIOS images, platform ID 0. > Options -boot-load-size, -no-emul-boot, > -boot-info-table affect this -b boot image. > > --efi-boot is for EFI images, platform id 0xef. > Hardcoded are: no emulation, no boot info table. > The load size is obtained from the size of the > EFI image file and rounded up to full 512 byte > blocks. > > Prone to change is the current rule that the > EFI image always is second if a BIOS image is > present. I will probably make this depending on > the sequence of options in future. > Please take care in grub-mkrescue to express > your desired sorting by giving -b before > --efi-boot. > > It's already so. > ------------------------------------------------ > > > Quote from El Torito 1.0 paragraph 2.3 > "The section header has an identification string. > If the BIOS understands the ID, string it may > choose to boot the system using one of these > entries in place of the INITIAL/DEFAULT entry." > > > What does that mean: "the BIOS understands" ? > Do we have to write something particular in > there for EFI ? > Any idea what one would have to write in case of > a 80x86-BIOS image ? > It looks like ISOs I had under the hand with multiple boot images just zero-fill this field. > The Validation Entry has an ID too. > But that is defined as quite meaningless: > "This is intended to identify the > manufacturer/developer of the CD-ROM." > > Actualy it seems like it can be an arbitrary string and BIOS doesn't care about it. Just setting it to all zeros is ok. Looking at few isos I had under the hand: FreeBSD ISOs: "The FreeBSD Project. h" NetBSD: "" DEbian GNU/Hurd: "" > > ------------------------------------------------ > > > Currently libisofs is able to write and read up > to 32 boot images. It writes each image entry > into an own section, but i plan to allow sections > of more than one image entry and user provided > ID strings. > > xorriso on the other hand got only a primitive > extension efi_path, which lives beneath bin_path. > This is not flexible. So i plan for improvements. > Nevertheless, the option sequence > -b ... --efi-boot ... > is promised to always lead to Vladimir's intended > boot catalog structure. > > ------------------------------------------------ > > > I tested with dummy boot images. > The boot catalog entries seem to be ok. > Now i am curious whether i misunderstood the > specs somewhere or whether it really would boot. > > > Have a nice day :) > > Thomas > > > > _______________________________________________ > Grub-devel mailing list > Grub-devel@gnu.org > http://lists.gnu.org/mailman/listinfo/grub-devel > > -- Regards Vladimir 'φ-coder/phcoder' Serbinenko
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