Re: [PATCH v4] x86/boot: Use efi_setup_data for searching RSDP on kexec-ed kernel

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Fri, Apr 12, 2019 at 10:49:56AM +0200, Borislav Petkov wrote:
> Now I need to go figure out whether there's a reliable way to know in
> the kexec kernel that it *is* a kexec kernel.

Actually, thinking about this more, we don't need to know whether the
kernel was kexeced or not. Why?

Because if it is kexec'ed, kexec(1) passes the required info in
setup_data. Now, if for whatever reason the kexec'ed kernel fails to
parse that EFI info and get the systab to figure out the RDSP, then it
doesn't have any other choice but fail booting.

Because there's no way it can figure out where the EFI runtime has been
mapped and recover by finding the RDSP from there.

So I think we're perfectly fine with the old approach:

        if (!pa)
                pa = kexec_get_rsdp_addr();

        if (!pa)
                pa = efi_get_rsdp_addr();


-- 
Regards/Gruss,
    Boris.

Good mailing practices for 400: avoid top-posting and trim the reply.

_______________________________________________
kexec mailing list
kexec@xxxxxxxxxxxxxxxxxxx
http://lists.infradead.org/mailman/listinfo/kexec



[Index of Archives]     [LM Sensors]     [Linux Sound]     [ALSA Users]     [ALSA Devel]     [Linux Audio Users]     [Linux Media]     [Kernel]     [Gimp]     [Yosemite News]     [Linux Media]

  Powered by Linux