On Thu, Oct 18, 2012 at 02:20:46PM -0700, Eric W. Biederman wrote: > Dave Young <dyoung at redhat.com> writes: > > > In case efi booting, kdump need kernel parameter acpi_rsdp= to retrieve > > the acpi root table physical address. > > > > Add a function cmdline_add_efi to get the address from /sys/firmware/efi/systab > > If there's no such file or read fail the function will just do nothing. > > > > Tested efi boot Fedora 17 on thinkpad T420. > > > > Some background info for this issue: > > http://lists.infradead.org/pipermail/kexec/2010-March/003889.html > > > > [v1 -> v2]: > > Address comments from Khalid and Simon > > use fgets instead of read(2) to iterate the file > > do not add 'noefi' because kexec does not construct EFI signature > > in bootloader signature in boot_params, so kexec'd kernel will > > disable EFI automatically even without noefi. > > I don't have any problems with this patch. > > I have a question. In the case where this fails are we successfully > passing the ACPI sections in the e820 map? > > If we are passing the acpi sections is that not enough for the kernel > to find the rdsp area? I'm just a bit surprised we need this patch > is all. > > Somehow it seems a bit ugly to pass information that could be conveyed > in the memory map on the command line. > > But I am all in favor of doing what works. > > Acked-by: "Eric W. Biederman" <ebiederm at xmission.com> Thanks, I have applied this patch.
