lkml.org 
[lkml]   [2013]   [Nov]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subjectx86: add xloadflags bit for efi runtime support on kexec
Old kexec-tools can not load new kernel. The reason is previously kexec-tools
do not fill efi_info in x86 setup header thus efi init fail and switch
to noefi boot. In new kexec-tools it will by default fill efi_info and
pass other efi required infomation to 2nd kernel so kexec kernel efi
initialization will success finally.

To prevent from breaking userspace, add a new xloadflags bit so kexec-tools
will check the flag and switch to old logic.

changelog:
Matt: +&& defined(CONFIG_KEXEC)
HPA: document the flag.

Signed-off-by: Dave Young <dyoung@redhat.com>
---
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(-)

--- efi.orig/arch/x86/boot/header.S
+++ efi/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
--- efi.orig/arch/x86/include/uapi/asm/bootparam.h
+++ efi/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__

--- efi.orig/Documentation/x86/boot.txt
+++ efi/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


\
 
 \ /
  Last update: 2013-11-25 10:21    [W:0.088 / U:0.544 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site