From: "Eric W. Biederman" The vmlinux on x86_64 does not report the correct physical address of the kernel. Instead in the physical address field it currently reports the virtual address of the kernel. This is patch is a bug fix that corrects vmlinux to report the proper physical addresses. This is potentially a help for crash dump analysis tools. This definitiely allows bootloaders that load vmlinux as a standard ELF executable. Bootloaders directly loading vmlinux become of practical importance when we consider the kexec on panic case. Signed-off-by: Eric Biederman Signed-off-by: Andrew Morton --- 25-akpm/arch/x86_64/Makefile | 2 25-akpm/arch/x86_64/kernel/vmlinux.lds.S | 130 ++++++++++++++++++++----------- 2 files changed, 88 insertions(+), 44 deletions(-) diff -puN arch/x86_64/kernel/vmlinux.lds.S~x86_64-vmlinux-fix-physical-addrs arch/x86_64/kernel/vmlinux.lds.S --- 25/arch/x86_64/kernel/vmlinux.lds.S~x86_64-vmlinux-fix-physical-addrs Wed Jan 19 15:22:14 2005 +++ 25-akpm/arch/x86_64/kernel/vmlinux.lds.S Wed Jan 19 15:22:14 2005 @@ -2,36 +2,41 @@ * Written by Martin Mares ; */ +#define LOAD_OFFSET __START_KERNEL_map + #include +#include #include OUTPUT_FORMAT("elf64-x86-64", "elf64-x86-64", "elf64-x86-64") OUTPUT_ARCH(i386:x86-64) -ENTRY(_start) +ENTRY(stext) jiffies_64 = jiffies; SECTIONS { - . = 0xffffffff80100000; + . = __START_KERNEL; _text = .; /* Text and read-only data */ - .text : { + .text : AT(ADDR(.text) - LOAD_OFFSET) { *(.text) SCHED_TEXT LOCK_TEXT *(.fixup) *(.gnu.warning) } = 0x9090 - .text.lock : { *(.text.lock) } /* out-of-line lock text */ + /* out-of-line lock text */ + .text.lock : AT(ADDR(.text.lock) - LOAD_OFFSET) { *(.text.lock) } _etext = .; /* End of text section */ . = ALIGN(16); /* Exception table */ __start___ex_table = .; - __ex_table : { *(__ex_table) } + __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) { *(__ex_table) } __stop___ex_table = .; RODATA - .data : { /* Data */ + /* Data */ + .data : AT(ADDR(.data) - LOAD_OFFSET) { *(.data) CONSTRUCTORS } @@ -39,62 +44,95 @@ SECTIONS _edata = .; /* End of data section */ __bss_start = .; /* BSS */ - .bss : { + .bss : AT(ADDR(.bss) - LOAD_OFFSET) { *(.bss.page_aligned) *(.bss) } __bss_end = .; + . = ALIGN(PAGE_SIZE); . = ALIGN(CONFIG_X86_L1_CACHE_BYTES); - .data.cacheline_aligned : { *(.data.cacheline_aligned) } + .data.cacheline_aligned : AT(ADDR(.data.cacheline_aligned) - LOAD_OFFSET) { + *(.data.cacheline_aligned) + } -#define AFTER(x) BINALIGN(LOADADDR(x) + SIZEOF(x), 16) -#define BINALIGN(x,y) (((x) + (y) - 1) & ~((y) - 1)) -#define CACHE_ALIGN(x) BINALIGN(x, CONFIG_X86_L1_CACHE_BYTES) +#define VSYSCALL_ADDR (-10*1024*1024) +#define VSYSCALL_PHYS_ADDR ((LOADADDR(.data.cacheline_aligned) + SIZEOF(.data.cacheline_aligned) + 4095) & ~(4095)) +#define VSYSCALL_VIRT_ADDR ((ADDR(.data.cacheline_aligned) + SIZEOF(.data.cacheline_aligned) + 4095) & ~(4095)) + +#define VLOAD_OFFSET (VSYSCALL_ADDR - VSYSCALL_PHYS_ADDR) +#define VLOAD(x) (ADDR(x) - VLOAD_OFFSET) + +#define VVIRT_OFFSET (VSYSCALL_ADDR - VSYSCALL_VIRT_ADDR) +#define VVIRT(x) (ADDR(x) - VVIRT_OFFSET) + + . = VSYSCALL_ADDR; + .vsyscall_0 : AT(VSYSCALL_PHYS_ADDR) { *(.vsyscall_0) } + __vsyscall_0 = VSYSCALL_VIRT_ADDR; - .vsyscall_0 -10*1024*1024: AT ((LOADADDR(.data.cacheline_aligned) + SIZEOF(.data.cacheline_aligned) + 4095) & ~(4095)) { *(.vsyscall_0) } - __vsyscall_0 = LOADADDR(.vsyscall_0); . = ALIGN(CONFIG_X86_L1_CACHE_BYTES); - .xtime_lock : AT CACHE_ALIGN(AFTER(.vsyscall_0)) { *(.xtime_lock) } - xtime_lock = LOADADDR(.xtime_lock); - .vxtime : AT AFTER(.xtime_lock) { *(.vxtime) } - vxtime = LOADADDR(.vxtime); - .wall_jiffies : AT AFTER(.vxtime) { *(.wall_jiffies) } - wall_jiffies = LOADADDR(.wall_jiffies); - .sys_tz : AT AFTER(.wall_jiffies) { *(.sys_tz) } - sys_tz = LOADADDR(.sys_tz); - .sysctl_vsyscall : AT AFTER(.sys_tz) { *(.sysctl_vsyscall) } - sysctl_vsyscall = LOADADDR(.sysctl_vsyscall); - .xtime : AT AFTER(.sysctl_vsyscall) { *(.xtime) } - xtime = LOADADDR(.xtime); + .xtime_lock : AT(VLOAD(.xtime_lock)) { *(.xtime_lock) } + xtime_lock = VVIRT(.xtime_lock); + + .vxtime : AT(VLOAD(.vxtime)) { *(.vxtime) } + vxtime = VVIRT(.vxtime); + + .wall_jiffies : AT(VLOAD(.wall_jiffies)) { *(.wall_jiffies) } + wall_jiffies = VVIRT(.wall_jiffies); + + .sys_tz : AT(VLOAD(.sys_tz)) { *(.sys_tz) } + sys_tz = VVIRT(.sys_tz); + + .sysctl_vsyscall : AT(VLOAD(.sysctl_vsyscall)) { *(.sysctl_vsyscall) } + sysctl_vsyscall = VVIRT(.sysctl_vsyscall); + + .xtime : AT(VLOAD(.xtime)) { *(.xtime) } + xtime = VVIRT(.xtime); + . = ALIGN(CONFIG_X86_L1_CACHE_BYTES); - .jiffies : AT CACHE_ALIGN(AFTER(.xtime)) { *(.jiffies) } - jiffies = LOADADDR(.jiffies); - .vsyscall_1 ADDR(.vsyscall_0) + 1024: AT (LOADADDR(.vsyscall_0) + 1024) { *(.vsyscall_1) } - . = LOADADDR(.vsyscall_0) + 4096; + .jiffies : AT(VLOAD(.jiffies)) { *(.jiffies) } + jiffies = VVIRT(.jiffies); + + .vsyscall_1 ADDR(.vsyscall_0) + 1024: AT(VLOAD(.vsyscall_1)) { *(.vsyscall_1) } + .vsyscall_2 ADDR(.vsyscall_0) + 2048: AT(VLOAD(.vsyscall_2)) { *(.vsyscall_2) } + .vsyscall_3 ADDR(.vsyscall_0) + 3072: AT(VLOAD(.vsyscall_3)) { *(.vsyscall_3) } + + . = VSYSCALL_VIRT_ADDR + 4096; + +#undef VSYSCALL_ADDR +#undef VSYSCALL_PHYS_ADDR +#undef VSYSCALL_VIRT_ADDR +#undef VLOAD_OFFSET +#undef VLOAD +#undef VVIRT_OFFSET +#undef VVIRT . = ALIGN(8192); /* init_task */ - .data.init_task : { *(.data.init_task) } + .data.init_task : AT(ADDR(.data.init_task) - LOAD_OFFSET) { + *(.data.init_task) + } . = ALIGN(4096); - .data.page_aligned : { *(.data.page_aligned) } + .data.page_aligned : AT(ADDR(.data.page_aligned) - LOAD_OFFSET) { + *(.data.page_aligned) + } . = ALIGN(4096); /* Init code and data */ __init_begin = .; - .init.text : { + .init.text : AT(ADDR(.init.text) - LOAD_OFFSET) { _sinittext = .; *(.init.text) _einittext = .; } __initdata_begin = .; - .init.data : { *(.init.data) } + .init.data : AT(ADDR(.init.data) - LOAD_OFFSET) { *(.init.data) } __initdata_end = .; . = ALIGN(16); __setup_start = .; - .init.setup : { *(.init.setup) } + .init.setup : AT(ADDR(.init.setup) - LOAD_OFFSET) { *(.init.setup) } __setup_end = .; __initcall_start = .; - .initcall.init : { + .initcall.init : AT(ADDR(.initcall.init) - LOAD_OFFSET) { *(.initcall1.init) *(.initcall2.init) *(.initcall3.init) @@ -105,32 +143,38 @@ SECTIONS } __initcall_end = .; __con_initcall_start = .; - .con_initcall.init : { *(.con_initcall.init) } + .con_initcall.init : AT(ADDR(.con_initcall.init) - LOAD_OFFSET) { + *(.con_initcall.init) + } __con_initcall_end = .; SECURITY_INIT . = ALIGN(8); __alt_instructions = .; - .altinstructions : { *(.altinstructions) } + .altinstructions : AT(ADDR(.altinstructions) - LOAD_OFFSET) { + *(.altinstructions) + } __alt_instructions_end = .; - .altinstr_replacement : { *(.altinstr_replacement) } + .altinstr_replacement : AT(ADDR(.altinstr_replacement) - LOAD_OFFSET) { + *(.altinstr_replacement) + } /* .exit.text is discard at runtime, not link time, to deal with references from .altinstructions and .eh_frame */ - .exit.text : { *(.exit.text) } - .exit.data : { *(.exit.data) } + .exit.text : AT(ADDR(.exit.text) - LOAD_OFFSET) { *(.exit.text) } + .exit.data : AT(ADDR(.exit.data) - LOAD_OFFSET) { *(.exit.data) } . = ALIGN(4096); __initramfs_start = .; - .init.ramfs : { *(.init.ramfs) } + .init.ramfs : AT(ADDR(.init.ramfs) - LOAD_OFFSET) { *(.init.ramfs) } __initramfs_end = .; . = ALIGN(32); __per_cpu_start = .; - .data.percpu : { *(.data.percpu) } + .data.percpu : AT(ADDR(.data.percpu) - LOAD_OFFSET) { *(.data.percpu) } __per_cpu_end = .; . = ALIGN(4096); __init_end = .; . = ALIGN(4096); __nosave_begin = .; - .data_nosave : { *(.data.nosave) } + .data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) { *(.data.nosave) } . = ALIGN(4096); __nosave_end = .; diff -puN arch/x86_64/Makefile~x86_64-vmlinux-fix-physical-addrs arch/x86_64/Makefile --- 25/arch/x86_64/Makefile~x86_64-vmlinux-fix-physical-addrs Wed Jan 19 15:22:14 2005 +++ 25-akpm/arch/x86_64/Makefile Wed Jan 19 15:22:14 2005 @@ -35,7 +35,7 @@ export IA32_CC IA32_LD IA32_AS IA32_OBJC LDFLAGS := -m elf_x86_64 OBJCOPYFLAGS := -O binary -R .note -R .comment -S -LDFLAGS_vmlinux := -e stext +LDFLAGS_vmlinux := CHECKFLAGS += -D__x86_64__ -m64 _