From fb45daa69d287b394eca1619b3fadff7c0215c71 Mon Sep 17 00:00:00 2001 From: Huang Ying Date: Fri, 15 Aug 2008 00:40:23 -0700 Subject: kexec jump: check code size in control page Kexec/Kexec-jump require code size in control page is less than PAGE_SIZE/2. This patch add link-time checking for this. ASSERT() of ld link script is used as the link-time checking mechanism. [akpm@linux-foundation.org: build fix] Signed-off-by: Huang Ying Cc: Pavel Machek Cc: "Rafael J. Wysocki" Cc: "Eric W. Biederman" Acked-by: Vivek Goyal Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86/kernel/relocate_kernel_32.S | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'arch/x86/kernel/relocate_kernel_32.S') diff --git a/arch/x86/kernel/relocate_kernel_32.S b/arch/x86/kernel/relocate_kernel_32.S index 703310a99023..6f50664b2ba5 100644 --- a/arch/x86/kernel/relocate_kernel_32.S +++ b/arch/x86/kernel/relocate_kernel_32.S @@ -20,10 +20,11 @@ #define PAGE_ATTR (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY) #define PAE_PGD_ATTR (_PAGE_PRESENT) -/* control_page + PAGE_SIZE/2 ~ control_page + PAGE_SIZE * 3/4 are - * used to save some data for jumping back +/* control_page + KEXEC_CONTROL_CODE_MAX_SIZE + * ~ control_page + PAGE_SIZE are used as data storage and stack for + * jumping back */ -#define DATA(offset) (PAGE_SIZE/2+(offset)) +#define DATA(offset) (KEXEC_CONTROL_CODE_MAX_SIZE+(offset)) /* Minimal CPU state */ #define ESP DATA(0x0) @@ -376,3 +377,6 @@ swap_pages: popl %ebx popl %ebp ret + + .globl kexec_control_code_size +.set kexec_control_code_size, . - relocate_kernel -- cgit v1.2.3