jonathan barkelew wrote:
UEFI Compatibility Issues in Fedora 10
I had gotten this fixed upstream, committed in the 2.6.29-rc8 kernel.
efi_ioremap was broken. This should also be in the latest rawhide
The second issue is far more pressing, and much more difficult to
solve. The linux kernel will behave
incorrectly if more than 400k of runtime memory is declared by system
firmware. The kernel attempts
to map all UEFI runtime memory into the kernel fixmap table, and any
requests to map more than 400k
are silently ignored. If this memory is accessed later in the boot
process (after transition to virtual
mode), the kernel will panic. It is my understanding that this
mechanism was designed to enable kexec
functionality, but this mechanism is UEFI non-compliant. If Fedora is
ever to be reliably booted on
UEFI systems, this issue must be addressed.
Perhaps you can verify the problem is resolved? If it is not resolved,
please let me know.
I had not tested the efi_ioremap fixes with kexec. I would appreciate
testing feedback if you have any (test with kernel >= 2.6.29-rc8)
I've briefly contacted the LKML, but after very
little discussion the issue was forgotten. I personally
don't know how to solve the runtime boot problem while still enabling
kexec, but it was my hope
that if the Fedora community were involved a solution might be found.