[PATCH]kdump: pass noefi and acpi_rsdp= to 2nd kernel

[Vivek Goyal]

On Wed, Sep 05, 2012 at 01:44:45PM +0800, Dave Young wrote:
> 
> In case efi booting, kdump need kernel parameter noefi and acpi_rsdp=
> to disable efi reinit and 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.
> 
> Signed-off-by: Dave Young <dyoung at redhat.com>
> ---
>  kexec/arch/i386/crashdump-x86.c |   47 ++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 47 insertions(+)
> 
> --- kexec-tools.orig/kexec/arch/i386/crashdump-x86.c
> +++ kexec-tools/kexec/arch/i386/crashdump-x86.c
> @@ -27,6 +27,7 @@
>  #include <sys/types.h>
>  #include <sys/stat.h>
>  #include <unistd.h>
> +#include <fcntl.h>
>  #include "../../kexec.h"
>  #include "../../kexec-elf.h"
>  #include "../../kexec-syscall.h"
> @@ -658,6 +659,51 @@ static int cmdline_add_memmap_acpi(char 
>  	return 0;
>  }
>  
> +/* Appends 'noefi acpi_rsdp=' commandline for efi boot crash dump */
> +static void cmdline_add_efi(char *cmdline)
> +{

Hi Dave,

It might be better to break it down in two functions. One for each
command line parameter.

Also, what's the corelation of efi and acpi_rsdp. Is acpi_rsdp required
only on EFI boot or in general it is required? If it is required in 
general, why kdump works currently.

Thanks
Vivek