From 456a29ddada79198c5965300e04103c40c481f62 Mon Sep 17 00:00:00 2001 From: Dave Young Date: Fri, 20 Dec 2013 18:02:20 +0800 Subject: [PATCH] x86: Add xloadflags bit for EFI runtime support on kexec Old kexec-tools can not load new kernels. The reason is kexec-tools does not fill efi_info in x86 setup header previously, thus EFI failed to initialize. In new kexec-tools it will by default to fill efi_info and pass other EFI required infomation to 2nd kernel so kexec kernel EFI initialization can succeed finally. To prevent from breaking userspace, add a new xloadflags bit so kexec-tools can check the flag and switch to old logic. Signed-off-by: Dave Young Acked-by: Borislav Petkov Tested-by: Toshi Kani Signed-off-by: Matt Fleming --- Documentation/x86/boot.txt | 3 +++ arch/x86/boot/header.S | 9 ++++++++- arch/x86/include/uapi/asm/bootparam.h | 1 + 3 files changed, 12 insertions(+), 1 deletion(-) diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt index f4f268c2b826..cb81741d3b0b 100644 --- a/Documentation/x86/boot.txt +++ b/Documentation/x86/boot.txt @@ -608,6 +608,9 @@ Protocol: 2.12+ - If 1, the kernel supports the 64-bit EFI handoff entry point given at handover_offset + 0x200. + Bit 4 (read): XLF_EFI_KEXEC + - If 1, the kernel supports kexec EFI boot with EFI runtime support. + Field name: cmdline_size Type: read Offset/size: 0x238/4 diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S index 9ec06a1f6d61..ec3b8ba68096 100644 --- a/arch/x86/boot/header.S +++ b/arch/x86/boot/header.S @@ -391,7 +391,14 @@ xloadflags: #else # define XLF23 0 #endif - .word XLF0 | XLF1 | XLF23 + +#if defined(CONFIG_X86_64) && defined(CONFIG_EFI) && defined(CONFIG_KEXEC) +# define XLF4 XLF_EFI_KEXEC +#else +# define XLF4 0 +#endif + + .word XLF0 | XLF1 | XLF23 | XLF4 cmdline_size: .long COMMAND_LINE_SIZE-1 #length of the command line, #added with boot protocol diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h index 64fe421aab65..225b0988043a 100644 --- a/arch/x86/include/uapi/asm/bootparam.h +++ b/arch/x86/include/uapi/asm/bootparam.h @@ -24,6 +24,7 @@ #define XLF_CAN_BE_LOADED_ABOVE_4G (1<<1) #define XLF_EFI_HANDOVER_32 (1<<2) #define XLF_EFI_HANDOVER_64 (1<<3) +#define XLF_EFI_KEXEC (1<<4) #ifndef __ASSEMBLY__ -- 2.11.0