From b4e0409a36f4533770a12095bde2a574a08a319e Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 21 Feb 2008 13:45:16 +0100 Subject: [PATCH] x86: check vmlinux limits, 64-bit these build-time and link-time checks would have prevented the vmlinux size regression. Signed-off-by: Ingo Molnar --- arch/x86/kernel/head64.c | 13 +++++++++++++ arch/x86/kernel/vmlinux_64.lds.S | 6 ++++++ arch/x86/mm/fault.c | 4 ---- 3 files changed, 19 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index ad2440832d..38f32e798a 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -82,6 +82,19 @@ void __init x86_64_start_kernel(char * real_mode_data) { int i; + /* + * Build-time sanity checks on the kernel image and module + * area mappings. (these are purely build-time and produce no code) + */ + BUILD_BUG_ON(MODULES_VADDR < KERNEL_IMAGE_START); + BUILD_BUG_ON(MODULES_VADDR-KERNEL_IMAGE_START < KERNEL_IMAGE_SIZE); + BUILD_BUG_ON(MODULES_LEN + KERNEL_IMAGE_SIZE > 2*PUD_SIZE); + BUILD_BUG_ON((KERNEL_IMAGE_START & ~PMD_MASK) != 0); + BUILD_BUG_ON((MODULES_VADDR & ~PMD_MASK) != 0); + BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL)); + BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) == + (__START_KERNEL & PGDIR_MASK))); + /* clear bss before set_intr_gate with early_idt_handler */ clear_bss(); diff --git a/arch/x86/kernel/vmlinux_64.lds.S b/arch/x86/kernel/vmlinux_64.lds.S index fab1322997..4c36945100 100644 --- a/arch/x86/kernel/vmlinux_64.lds.S +++ b/arch/x86/kernel/vmlinux_64.lds.S @@ -247,3 +247,9 @@ SECTIONS DWARF_DEBUG } + +/* + * Build-time check on the image size: + */ +ASSERT((_end - _text <= KERNEL_IMAGE_SIZE), + "kernel image bigger than KERNEL_IMAGE_SIZE") diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index ec08d83898..81fcbeec38 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -976,9 +976,5 @@ void vmalloc_sync_all(void) if (address == start) start = address + PGDIR_SIZE; } - /* Check that there is no need to do the same for the modules area. */ - BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL)); - BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) == - (__START_KERNEL & PGDIR_MASK))); #endif } -- 2.39.5