Am 16.10.2012 16:19, schrieb Richard W.M. Jones:
[Bug: https://bugzilla.redhat.com/show_bug.cgi?id=866664] Here's the situation, since the bug doesn't explain it well. (1) qemu can run any architecture on any other architecture, using software emulation. eg. It can run x86_64 guest operating systems on top of ppc64 hosts (albeit not at full speed). (2) In order to run guests, you have to provide a BIOS (or some sort of other boot ROM), since most guests wouldn't be able to boot without BIOS services. This applies for all guests, but of particular interest to us are i686/x86_64 guests. (3) SeaBIOS is a free, open source PC BIOS implementation. It is what we use to provide services to i686/x86_64 PC guests. (4) Although qemu itself bundles some binary BIOSes, in Fedora we have chosen to recompile these from source. We now (on i686/x86_64) compile or cross-compile all ROMs from source. (5) 'seabios-bin' is the name of the RPM package that contains the SeaBIOS ROMs. I have no idea why (historical?) this package has '-bin' in the name, but the important point is that it is NOT a binary-only package. It is built from source. (6) In order to compile SeaBIOS you need a program called 'iasl' (part of the ACPICA.org project). This program is needed to compile the ACPI tables which are an integral part of the ROM data that is needed for i686/x86_64 guests to boot. (7) Unfortunately the iasl program, which runs fine on little-endian platforms, has endianness issues. Such that when you run it on a ppc64 host it produces big-endian ACPI tables, which are of course completely broken. 'iasl' itself is a very large program, and I do not know the scope of the fix for this issue -- it may be trivial, or it may require auditing every line of code. Therefore: We would like a packaging exception which would allow us to import the seabios-bin package (built on little-endian) into the ppc & ppc64 buildroots. Rich.
I'm all for it. We wouldn't ship a binary without sources, just one that got compiled on a x86 Fedora builder and got repackaged for PPC. As you can see in bugzillas 866664, 856856 and 865013, fixing iasl might become a major effort and the other option of dropping x86 support in the PPC qemu doesn't seem the right thing to do here.
Karsten (PPC secondary arch maintainer) -- packaging mailing list packaging@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/packaging
