Re: [PATCH] export efi.flags to sysfs

[Fleming, Matt]

On 29 May 2014 13:59, Vivek Goyal <vgoyal@xxxxxxxxxx> wrote:
>
> Only second kernel boots with "noefi" and this parameter is appened by
> kexec-tools to second kernel command line. So first kernel will still
> boot *without noefi* and kexec-tools wil think that this system support
> booting second kernel with UEFI enabled.
>
> I don't know if we export /sys/firmware/efi/runtime-map/ in case of
> non 1:1 mapping or not. Dave and Boris will know better.

Looking at the code the answer is: yes. I think that's the bug right there.

By exporting entries in /sys/firmware/efi/runtime-map we're saying
"These mappings persist across kexec, you can trust that they won't
change", for SGI UV (which currently uses the quirk) or if you boot
with efi=old_map on the command line, that's simply not true.

So, it would seem to me that we're missing a "if
(efi_enabled(OLD_MAP))" in drivers/firmware/efi/runtime-map.c.
Borislav, Dave? What do you guys think?

This is all assuming that the root of the regression is that
kexec-tools sees entries in /sys/firmware/efi/runtime-map/ and says
"Yay! EFI boot!".
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/