diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-16 17:10:02 (GMT) |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-16 17:10:02 (GMT) |
commit | e7fd3b4669f5b835c8afce28425d9f698a558115 (patch) | |
tree | d7f254a1d75807cc8b50f416ba3bd13010913ddc /arch | |
parent | fc82e1d59a24cbac01c49d4eb3b28d6abc26a5f4 (diff) | |
parent | 2ae9d293b14d17f35eff624272cfecac7979a2ee (diff) | |
download | linux-e7fd3b4669f5b835c8afce28425d9f698a558115.tar.xz |
Merge branch 'x86-trampoline-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-trampoline-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: Fix binutils-2.21 symbol related build failures
x86-64, trampoline: Remove unused variable
x86, reboot: Fix the use of passed arguments in 32-bit BIOS reboot
x86, reboot: Move the real-mode reboot code to an assembly file
x86: Make the GDT_ENTRY() macro in <asm/segment.h> safe for assembly
x86, trampoline: Use the unified trampoline setup for ACPI wakeup
x86, trampoline: Common infrastructure for low memory trampolines
Fix up trivial conflicts in arch/x86/kernel/Makefile
Diffstat (limited to 'arch')
-rw-r--r-- | arch/x86/Kconfig | 4 | ||||
-rw-r--r-- | arch/x86/include/asm/acpi.h | 4 | ||||
-rw-r--r-- | arch/x86/include/asm/reboot.h | 5 | ||||
-rw-r--r-- | arch/x86/include/asm/segment.h | 12 | ||||
-rw-r--r-- | arch/x86/include/asm/trampoline.h | 33 | ||||
-rw-r--r-- | arch/x86/kernel/Makefile | 4 | ||||
-rw-r--r-- | arch/x86/kernel/acpi/realmode/wakeup.S | 21 | ||||
-rw-r--r-- | arch/x86/kernel/acpi/realmode/wakeup.h | 5 | ||||
-rw-r--r-- | arch/x86/kernel/acpi/realmode/wakeup.lds.S | 28 | ||||
-rw-r--r-- | arch/x86/kernel/acpi/sleep.c | 65 | ||||
-rw-r--r-- | arch/x86/kernel/acpi/sleep.h | 3 | ||||
-rw-r--r-- | arch/x86/kernel/acpi/wakeup_rm.S | 12 | ||||
-rw-r--r-- | arch/x86/kernel/apm_32.c | 12 | ||||
-rw-r--r-- | arch/x86/kernel/entry_32.S | 2 | ||||
-rw-r--r-- | arch/x86/kernel/head32.c | 9 | ||||
-rw-r--r-- | arch/x86/kernel/head_64.S | 3 | ||||
-rw-r--r-- | arch/x86/kernel/reboot.c | 120 | ||||
-rw-r--r-- | arch/x86/kernel/reboot_32.S | 135 | ||||
-rw-r--r-- | arch/x86/kernel/setup.c | 9 | ||||
-rw-r--r-- | arch/x86/kernel/smpboot.c | 10 | ||||
-rw-r--r-- | arch/x86/kernel/trampoline.c | 42 | ||||
-rw-r--r-- | arch/x86/kernel/trampoline_32.S | 15 | ||||
-rw-r--r-- | arch/x86/kernel/trampoline_64.S | 28 | ||||
-rw-r--r-- | arch/x86/kernel/vmlinux.lds.S | 13 |
24 files changed, 314 insertions, 280 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index fe6a5f8..e1f65c4 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -221,10 +221,6 @@ config X86_HT def_bool y depends on SMP -config X86_TRAMPOLINE - def_bool y - depends on SMP || (64BIT && ACPI_SLEEP) - config X86_32_LAZY_GS def_bool y depends on X86_32 && !CC_STACKPROTECTOR diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h index b964ec4..448d73a 100644 --- a/arch/x86/include/asm/acpi.h +++ b/arch/x86/include/asm/acpi.h @@ -29,6 +29,7 @@ #include <asm/processor.h> #include <asm/mmu.h> #include <asm/mpspec.h> +#include <asm/trampoline.h> #define COMPILER_DEPENDENT_INT64 long long #define COMPILER_DEPENDENT_UINT64 unsigned long long @@ -117,7 +118,8 @@ static inline void acpi_disable_pci(void) extern int acpi_save_state_mem(void); extern void acpi_restore_state_mem(void); -extern unsigned long acpi_wakeup_address; +extern const unsigned char acpi_wakeup_code[]; +#define acpi_wakeup_address (__pa(TRAMPOLINE_SYM(acpi_wakeup_code))) /* early initialization routine */ extern void acpi_reserve_wakeup_memory(void); diff --git a/arch/x86/include/asm/reboot.h b/arch/x86/include/asm/reboot.h index 562d4fd..3250e3d 100644 --- a/arch/x86/include/asm/reboot.h +++ b/arch/x86/include/asm/reboot.h @@ -18,7 +18,10 @@ extern struct machine_ops machine_ops; void native_machine_crash_shutdown(struct pt_regs *regs); void native_machine_shutdown(void); -void machine_real_restart(const unsigned char *code, int length); +void machine_real_restart(unsigned int type); +/* These must match dispatch_table in reboot_32.S */ +#define MRR_BIOS 0 +#define MRR_APM 1 typedef void (*nmi_shootdown_cb)(int, struct die_args*); void nmi_shootdown_cpus(nmi_shootdown_cb callback); diff --git a/arch/x86/include/asm/segment.h b/arch/x86/include/asm/segment.h index 231f1c1..cd84f72 100644 --- a/arch/x86/include/asm/segment.h +++ b/arch/x86/include/asm/segment.h @@ -1,14 +1,16 @@ #ifndef _ASM_X86_SEGMENT_H #define _ASM_X86_SEGMENT_H +#include <linux/const.h> + /* Constructor for a conventional segment GDT (or LDT) entry */ /* This is a macro so it can be used in initializers */ #define GDT_ENTRY(flags, base, limit) \ - ((((base) & 0xff000000ULL) << (56-24)) | \ - (((flags) & 0x0000f0ffULL) << 40) | \ - (((limit) & 0x000f0000ULL) << (48-16)) | \ - (((base) & 0x00ffffffULL) << 16) | \ - (((limit) & 0x0000ffffULL))) + ((((base) & _AC(0xff000000,ULL)) << (56-24)) | \ + (((flags) & _AC(0x0000f0ff,ULL)) << 40) | \ + (((limit) & _AC(0x000f0000,ULL)) << (48-16)) | \ + (((base) & _AC(0x00ffffff,ULL)) << 16) | \ + (((limit) & _AC(0x0000ffff,ULL)))) /* Simple and small GDT entries for booting only */ diff --git a/arch/x86/include/asm/trampoline.h b/arch/x86/include/asm/trampoline.h index f4500fb..feca311 100644 --- a/arch/x86/include/asm/trampoline.h +++ b/arch/x86/include/asm/trampoline.h @@ -3,25 +3,36 @@ #ifndef __ASSEMBLY__ -#ifdef CONFIG_X86_TRAMPOLINE +#include <linux/types.h> +#include <asm/io.h> + /* - * Trampoline 80x86 program as an array. + * Trampoline 80x86 program as an array. These are in the init rodata + * segment, but that's okay, because we only care about the relative + * addresses of the symbols. */ -extern const unsigned char trampoline_data []; -extern const unsigned char trampoline_end []; -extern unsigned char *trampoline_base; +extern const unsigned char x86_trampoline_start []; +extern const unsigned char x86_trampoline_end []; +extern unsigned char *x86_trampoline_base; extern unsigned long init_rsp; extern unsigned long initial_code; extern unsigned long initial_gs; -#define TRAMPOLINE_SIZE roundup(trampoline_end - trampoline_data, PAGE_SIZE) +extern void __init setup_trampolines(void); + +extern const unsigned char trampoline_data[]; +extern const unsigned char trampoline_status[]; + +#define TRAMPOLINE_SYM(x) \ + ((void *)(x86_trampoline_base + \ + ((const unsigned char *)(x) - x86_trampoline_start))) -extern unsigned long setup_trampoline(void); -extern void __init reserve_trampoline_memory(void); -#else -static inline void reserve_trampoline_memory(void) {} -#endif /* CONFIG_X86_TRAMPOLINE */ +/* Address of the SMP trampoline */ +static inline unsigned long trampoline_address(void) +{ + return virt_to_phys(TRAMPOLINE_SYM(trampoline_data)); +} #endif /* __ASSEMBLY__ */ diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 62445ba..743642f 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -47,7 +47,7 @@ obj-y += tsc.o io_delay.o rtc.o obj-y += pci-iommu_table.o obj-y += resource.o -obj-$(CONFIG_X86_TRAMPOLINE) += trampoline.o +obj-y += trampoline.o trampoline_$(BITS).o obj-y += process.o obj-y += i387.o xsave.o obj-y += ptrace.o @@ -59,6 +59,7 @@ obj-$(CONFIG_STACKTRACE) += stacktrace.o obj-y += cpu/ obj-y += acpi/ obj-y += reboot.o +obj-$(CONFIG_X86_32) += reboot_32.o obj-$(CONFIG_MCA) += mca_32.o obj-$(CONFIG_X86_MSR) += msr.o obj-$(CONFIG_X86_CPUID) += cpuid.o @@ -69,7 +70,6 @@ obj-$(CONFIG_SMP) += smp.o obj-$(CONFIG_SMP) += smpboot.o obj-$(CONFIG_SMP) += tsc_sync.o obj-$(CONFIG_SMP) += setup_percpu.o -obj-$(CONFIG_X86_TRAMPOLINE) += trampoline_$(BITS).o obj-$(CONFIG_X86_MPPARSE) += mpparse.o obj-y += apic/ obj-$(CONFIG_X86_REBOOTFIXUPS) += reboot_fixups_32.o diff --git a/arch/x86/kernel/acpi/realmode/wakeup.S b/arch/x86/kernel/acpi/realmode/wakeup.S index 28595d6..ead21b6 100644 --- a/arch/x86/kernel/acpi/realmode/wakeup.S +++ b/arch/x86/kernel/acpi/realmode/wakeup.S @@ -6,11 +6,17 @@ #include <asm/page_types.h> #include <asm/pgtable_types.h> #include <asm/processor-flags.h> +#include "wakeup.h" .code16 - .section ".header", "a" + .section ".jump", "ax" + .globl _start +_start: + cli + jmp wakeup_code /* This should match the structure in wakeup.h */ + .section ".header", "a" .globl wakeup_header wakeup_header: video_mode: .short 0 /* Video mode number */ @@ -30,14 +36,11 @@ wakeup_jmp: .byte 0xea /* ljmpw */ wakeup_jmp_off: .word 3f wakeup_jmp_seg: .word 0 wakeup_gdt: .quad 0, 0, 0 -signature: .long 0x51ee1111 +signature: .long WAKEUP_HEADER_SIGNATURE .text - .globl _start .code16 wakeup_code: -_start: - cli cld /* Apparently some dimwit BIOS programmers don't know how to @@ -77,12 +80,12 @@ _start: /* Check header signature... */ movl signature, %eax - cmpl $0x51ee1111, %eax + cmpl $WAKEUP_HEADER_SIGNATURE, %eax jne bogus_real_magic /* Check we really have everything... */ movl end_signature, %eax - cmpl $0x65a22c82, %eax + cmpl $WAKEUP_END_SIGNATURE, %eax jne bogus_real_magic /* Call the C code */ @@ -147,3 +150,7 @@ wakeup_heap: wakeup_stack: .space 2048 wakeup_stack_end: + + .section ".signature","a" +end_signature: + .long WAKEUP_END_SIGNATURE diff --git a/arch/x86/kernel/acpi/realmode/wakeup.h b/arch/x86/kernel/acpi/realmode/wakeup.h index 69d38d0..e1828c0 100644 --- a/arch/x86/kernel/acpi/realmode/wakeup.h +++ b/arch/x86/kernel/acpi/realmode/wakeup.h @@ -35,7 +35,8 @@ struct wakeup_header { extern struct wakeup_header wakeup_header; #endif -#define HEADER_OFFSET 0x3f00 -#define WAKEUP_SIZE 0x4000 +#define WAKEUP_HEADER_OFFSET 8 +#define WAKEUP_HEADER_SIGNATURE 0x51ee1111 +#define WAKEUP_END_SIGNATURE 0x65a22c82 #endif /* ARCH_X86_KERNEL_ACPI_RM_WAKEUP_H */ diff --git a/arch/x86/kernel/acpi/realmode/wakeup.lds.S b/arch/x86/kernel/acpi/realmode/wakeup.lds.S index 060fff8..d4f8010 100644 --- a/arch/x86/kernel/acpi/realmode/wakeup.lds.S +++ b/arch/x86/kernel/acpi/realmode/wakeup.lds.S @@ -13,9 +13,19 @@ ENTRY(_start) SECTIONS { . = 0; + .jump : { + *(.jump) + } = 0x90909090 + + . = WAKEUP_HEADER_OFFSET; + .header : { + *(.header) + } + + . = ALIGN(16); .text : { *(.text*) - } + } = 0x90909090 . = ALIGN(16); .rodata : { @@ -33,11 +43,6 @@ SECTIONS *(.data*) } - .signature : { - end_signature = .; - LONG(0x65a22c82) - } - . = ALIGN(16); .bss : { __bss_start = .; @@ -45,20 +50,13 @@ SECTIONS __bss_end = .; } - . = HEADER_OFFSET; - .header : { - *(.header) + .signature : { + *(.signature) } - . = ALIGN(16); _end = .; /DISCARD/ : { *(.note*) } - - /* - * The ASSERT() sink to . is intentional, for binutils 2.14 compatibility: - */ - . = ASSERT(_end <= WAKEUP_SIZE, "Wakeup too big!"); } diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c index 68d1537..4572c58 100644 --- a/arch/x86/kernel/acpi/sleep.c +++ b/arch/x86/kernel/acpi/sleep.c @@ -18,12 +18,8 @@ #include "realmode/wakeup.h" #include "sleep.h" -unsigned long acpi_wakeup_address; unsigned long acpi_realmode_flags; -/* address in low memory of the wakeup routine. */ -static unsigned long acpi_realmode; - #if defined(CONFIG_SMP) && defined(CONFIG_64BIT) static char temp_stack[4096]; #endif @@ -33,22 +29,17 @@ static char temp_stack[4096]; * * Create an identity mapped page table and copy the wakeup routine to * low memory. - * - * Note that this is too late to change acpi_wakeup_address. */ int acpi_save_state_mem(void) { struct wakeup_header *header; + /* address in low memory of the wakeup routine. */ + char *acpi_realmode; - if (!acpi_realmode) { - printk(KERN_ERR "Could not allocate memory during boot, " - "S3 disabled\n"); - return -ENOMEM; - } - memcpy((void *)acpi_realmode, &wakeup_code_start, WAKEUP_SIZE); + acpi_realmode = TRAMPOLINE_SYM(acpi_wakeup_code); - header = (struct wakeup_header *)(acpi_realmode + HEADER_OFFSET); - if (header->signature != 0x51ee1111) { + header = (struct wakeup_header *)(acpi_realmode + WAKEUP_HEADER_OFFSET); + if (header->signature != WAKEUP_HEADER_SIGNATURE) { printk(KERN_ERR "wakeup header does not match\n"); return -EINVAL; } @@ -68,9 +59,7 @@ int acpi_save_state_mem(void) /* GDT[0]: GDT self-pointer */ header->wakeup_gdt[0] = (u64)(sizeof(header->wakeup_gdt) - 1) + - ((u64)(acpi_wakeup_address + - ((char *)&header->wakeup_gdt - (char *)acpi_realmode)) - << 16); + ((u64)__pa(&header->wakeup_gdt) << 16); /* GDT[1]: big real mode-like code segment */ header->wakeup_gdt[1] = GDT_ENTRY(0x809b, acpi_wakeup_address, 0xfffff); @@ -96,7 +85,7 @@ int acpi_save_state_mem(void) header->pmode_cr3 = (u32)__pa(&initial_page_table); saved_magic = 0x12345678; #else /* CONFIG_64BIT */ - header->trampoline_segment = setup_trampoline() >> 4; + header->trampoline_segment = trampoline_address() >> 4; #ifdef CONFIG_SMP stack_start = (unsigned long)temp_stack + sizeof(temp_stack); early_gdt_descr.address = @@ -117,46 +106,6 @@ void acpi_restore_state_mem(void) { } - -/** - * acpi_reserve_wakeup_memory - do _very_ early ACPI initialisation - * - * We allocate a page from the first 1MB of memory for the wakeup - * routine for when we come back from a sleep state. The - * runtime allocator allows specification of <16MB pages, but not - * <1MB pages. - */ -void __init acpi_reserve_wakeup_memory(void) -{ - phys_addr_t mem; - - if ((&wakeup_code_end - &wakeup_code_start) > WAKEUP_SIZE) { - printk(KERN_ERR - "ACPI: Wakeup code way too big, S3 disabled.\n"); - return; - } - - mem = memblock_find_in_range(0, 1<<20, WAKEUP_SIZE, PAGE_SIZE); - - if (mem == MEMBLOCK_ERROR) { - printk(KERN_ERR "ACPI: Cannot allocate lowmem, S3 disabled.\n"); - return; - } - acpi_realmode = (unsigned long) phys_to_virt(mem); - acpi_wakeup_address = mem; - memblock_x86_reserve_range(mem, mem + WAKEUP_SIZE, "ACPI WAKEUP"); -} - -int __init acpi_configure_wakeup_memory(void) -{ - if (acpi_realmode) - set_memory_x(acpi_realmode, WAKEUP_SIZE >> PAGE_SHIFT); - - return 0; -} -arch_initcall(acpi_configure_wakeup_memory); - - static int __init acpi_sleep_setup(char *str) { while ((str != NULL) && (*str != '\0')) { diff --git a/arch/x86/kernel/acpi/sleep.h b/arch/x86/kernel/acpi/sleep.h index adbcbaa..86ba1c8 100644 --- a/arch/x86/kernel/acpi/sleep.h +++ b/arch/x86/kernel/acpi/sleep.h @@ -4,13 +4,10 @@ #include <asm/trampoline.h> -extern char wakeup_code_start, wakeup_code_end; - extern unsigned long saved_video_mode; extern long saved_magic; extern int wakeup_pmode_return; -extern char swsusp_pg_dir[PAGE_SIZE]; extern unsigned long acpi_copy_wakeup_routine(unsigned long); extern void wakeup_long64(void); diff --git a/arch/x86/kernel/acpi/wakeup_rm.S b/arch/x86/kernel/acpi/wakeup_rm.S index 6ff3b57..63b8ab5 100644 --- a/arch/x86/kernel/acpi/wakeup_rm.S +++ b/arch/x86/kernel/acpi/wakeup_rm.S @@ -2,9 +2,11 @@ * Wrapper script for the realmode binary as a transport object * before copying to low memory. */ - .section ".rodata","a" - .globl wakeup_code_start, wakeup_code_end -wakeup_code_start: +#include <asm/page_types.h> + + .section ".x86_trampoline","a" + .balign PAGE_SIZE + .globl acpi_wakeup_code +acpi_wakeup_code: .incbin "arch/x86/kernel/acpi/realmode/wakeup.bin" -wakeup_code_end: - .size wakeup_code_start, .-wakeup_code_start + .size acpi_wakeup_code, .-acpi_wakeup_code diff --git a/arch/x86/kernel/apm_32.c b/arch/x86/kernel/apm_32.c index 15f47f7..9079926 100644 --- a/arch/x86/kernel/apm_32.c +++ b/arch/x86/kernel/apm_32.c @@ -976,20 +976,10 @@ recalc: static void apm_power_off(void) { - unsigned char po_bios_call[] = { - 0xb8, 0x00, 0x10, /* movw $0x1000,ax */ - 0x8e, 0xd0, /* movw ax,ss */ - 0xbc, 0x00, 0xf0, /* movw $0xf000,sp */ - 0xb8, 0x07, 0x53, /* movw $0x5307,ax */ - 0xbb, 0x01, 0x00, /* movw $0x0001,bx */ - 0xb9, 0x03, 0x00, /* movw $0x0003,cx */ - 0xcd, 0x15 /* int $0x15 */ - }; - /* Some bioses don't like being called from CPU != 0 */ if (apm_info.realmode_power_off) { set_cpus_allowed_ptr(current, cpumask_of(0)); - machine_real_restart(po_bios_call, sizeof(po_bios_call)); + machine_real_restart(MRR_APM); } else { (void)set_system_power_state(APM_STATE_OFF); } diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S index fa41f72..5c1a9197 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -1414,7 +1414,7 @@ ENTRY(async_page_fault) pushl_cfi $do_async_page_fault jmp error_code CFI_ENDPROC -END(apf_page_fault) +END(async_page_fault) #endif /* diff --git a/arch/x86/kernel/head32.c b/arch/x86/kernel/head32.c index 7f138b3..d6d6bb3 100644 --- a/arch/x86/kernel/head32.c +++ b/arch/x86/kernel/head32.c @@ -34,15 +34,6 @@ void __init i386_start_kernel(void) { memblock_init(); -#ifdef CONFIG_X86_TRAMPOLINE - /* - * But first pinch a few for the stack/trampoline stuff - * FIXME: Don't need the extra page at 4K, but need to fix - * trampoline before removing it. (see the GDT stuff) - */ - memblock_x86_reserve_range(PAGE_SIZE, PAGE_SIZE + PAGE_SIZE, "EX TRAMPOLINE"); -#endif - memblock_x86_reserve_range(__pa_symbol(&_text), __pa_symbol(&__bss_stop), "TEXT DATA BSS"); #ifdef CONFIG_BLK_DEV_INITRD diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 239046b..e11e394 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -136,10 +136,9 @@ ident_complete: /* Fixup phys_base */ addq %rbp, phys_base(%rip) -#ifdef CONFIG_X86_TRAMPOLINE + /* Fixup trampoline */ addq %rbp, trampoline_level4_pgt + 0(%rip) addq %rbp, trampoline_level4_pgt + (511*8)(%rip) -#endif /* Due to ENTRY(), sometimes the empty space gets filled with * zeros. Better take a jmp than relying on empty space being diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index 715037c..d3ce37e 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -303,68 +303,16 @@ static int __init reboot_init(void) } core_initcall(reboot_init); -/* The following code and data reboots the machine by switching to real - mode and jumping to the BIOS reset entry point, as if the CPU has - really been reset. The previous version asked the keyboard - controller to pulse the CPU reset line, which is more thorough, but - doesn't work with at least one type of 486 motherboard. It is easy - to stop this code working; hence the copious comments. */ -static const unsigned long long -real_mode_gdt_entries [3] = -{ - 0x0000000000000000ULL, /* Null descriptor */ - 0x00009b000000ffffULL, /* 16-bit real-mode 64k code at 0x00000000 */ - 0x000093000100ffffULL /* 16-bit real-mode 64k data at 0x00000100 */ -}; +extern const unsigned char machine_real_restart_asm[]; +extern const u64 machine_real_restart_gdt[3]; -static const struct desc_ptr -real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, (long)real_mode_gdt_entries }, -real_mode_idt = { 0x3ff, 0 }; - -/* This is 16-bit protected mode code to disable paging and the cache, - switch to real mode and jump to the BIOS reset code. - - The instruction that switches to real mode by writing to CR0 must be - followed immediately by a far jump instruction, which set CS to a - valid value for real mode, and flushes the prefetch queue to avoid - running instructions that have already been decoded in protected - mode. - - Clears all the flags except ET, especially PG (paging), PE - (protected-mode enable) and TS (task switch for coprocessor state - save). Flushes the TLB after paging has been disabled. Sets CD and - NW, to disable the cache on a 486, and invalidates the cache. This - is more like the state of a 486 after reset. I don't know if - something else should be done for other chips. - - More could be done here to set up the registers as if a CPU reset had - occurred; hopefully real BIOSs don't assume much. */ -static const unsigned char real_mode_switch [] = -{ - 0x66, 0x0f, 0x20, 0xc0, /* movl %cr0,%eax */ - 0x66, 0x83, 0xe0, 0x11, /* andl $0x00000011,%eax */ - 0x66, 0x0d, 0x00, 0x00, 0x00, 0x60, /* orl $0x60000000,%eax */ - 0x66, 0x0f, 0x22, 0xc0, /* movl %eax,%cr0 */ - 0x66, 0x0f, 0x22, 0xd8, /* movl %eax,%cr3 */ - 0x66, 0x0f, 0x20, 0xc3, /* movl %cr0,%ebx */ - 0x66, 0x81, 0xe3, 0x00, 0x00, 0x00, 0x60, /* andl $0x60000000,%ebx */ - 0x74, 0x02, /* jz f */ - 0x0f, 0x09, /* wbinvd */ - 0x24, 0x10, /* f: andb $0x10,al */ - 0x66, 0x0f, 0x22, 0xc0 /* movl %eax,%cr0 */ -}; -static const unsigned char jump_to_bios [] = +void machine_real_restart(unsigned int type) { - 0xea, 0x00, 0x00, 0xff, 0xff /* ljmp $0xffff,$0x0000 */ -}; + void *restart_va; + unsigned long restart_pa; + void (*restart_lowmem)(unsigned int); + u64 *lowmem_gdt; -/* - * Switch to real mode and then execute the code - * specified by the code and length parameters. - * We assume that length will aways be less that 100! - */ -void machine_real_restart(const unsigned char *code, int length) -{ local_irq_disable(); /* Write zero to CMOS register number 0x0f, which the BIOS POST @@ -392,41 +340,23 @@ void machine_real_restart(const unsigned char *code, int length) too. */ *((unsigned short *)0x472) = reboot_mode; - /* For the switch to real mode, copy some code to low memory. It has - to be in the first 64k because it is running in 16-bit mode, and it - has to have the same physical and virtual address, because it turns - off paging. Copy it near the end of the first page, out of the way - of BIOS variables. */ - memcpy((void *)(0x1000 - sizeof(real_mode_switch) - 100), - real_mode_switch, sizeof (real_mode_switch)); - memcpy((void *)(0x1000 - 100), code, length); - - /* Set up the IDT for real mode. */ - load_idt(&real_mode_idt); - - /* Set up a GDT from which we can load segment descriptors for real - mode. The GDT is not used in real mode; it is just needed here to - prepare the descriptors. */ - load_gdt(&real_mode_gdt); - - /* Load the data segment registers, and thus the descriptors ready for - real mode. The base address of each segment is 0x100, 16 times the - selector value being loaded here. This is so that the segment - registers don't have to be reloaded after switching to real mode: - the values are consistent for real mode operation already. */ - __asm__ __volatile__ ("movl $0x0010,%%eax\n" - "\tmovl %%eax,%%ds\n" - "\tmovl %%eax,%%es\n" - "\tmovl %%eax,%%fs\n" - "\tmovl %%eax,%%gs\n" - "\tmovl %%eax,%%ss" : : : "eax"); - - /* Jump to the 16-bit code that we copied earlier. It disables paging - and the cache, switches to real mode, and jumps to the BIOS reset - entry point. */ - __asm__ __volatile__ ("ljmp $0x0008,%0" - : - : "i" ((void *)(0x1000 - sizeof (real_mode_switch) - 100))); + /* Patch the GDT in the low memory trampoline */ + lowmem_gdt = TRAMPOLINE_SYM(machine_real_restart_gdt); + + restart_va = TRAMPOLINE_SYM(machine_real_restart_asm); + restart_pa = virt_to_phys(restart_va); + restart_lowmem = (void (*)(unsigned int))restart_pa; + + /* GDT[0]: GDT self-pointer */ + lowmem_gdt[0] = + (u64)(sizeof(machine_real_restart_gdt) - 1) + + ((u64)virt_to_phys(lowmem_gdt) << 16); + /* GDT[1]: 64K real mode code segment */ + lowmem_gdt[1] = + GDT_ENTRY(0x009b, restart_pa, 0xffff); + + /* Jump to the identity-mapped low memory code */ + restart_lowmem(type); } #ifdef CONFIG_APM_MODULE EXPORT_SYMBOL(machine_real_restart); @@ -581,7 +511,7 @@ static void native_machine_emergency_restart(void) #ifdef CONFIG_X86_32 case BOOT_BIOS: - machine_real_restart(jump_to_bios, sizeof(jump_to_bios)); + machine_real_restart(MRR_BIOS); reboot_type = BOOT_KBD; break; diff --git a/arch/x86/kernel/reboot_32.S b/arch/x86/kernel/reboot_32.S new file mode 100644 index 0000000..29092b3 --- /dev/null +++ b/arch/x86/kernel/reboot_32.S @@ -0,0 +1,135 @@ +#include <linux/linkage.h> +#include <linux/init.h> +#include <asm/segment.h> +#include <asm/page_types.h> + +/* + * The following code and data reboots the machine by switching to real + * mode and jumping to the BIOS reset entry point, as if the CPU has + * really been reset. The previous version asked the keyboard + * controller to pulse the CPU reset line, which is more thorough, but + * doesn't work with at least one type of 486 motherboard. It is easy + * to stop this code working; hence the copious comments. + * + * This code is called with the restart type (0 = BIOS, 1 = APM) in %eax. + */ + .section ".x86_trampoline","a" + .balign 16 + .code32 +ENTRY(machine_real_restart_asm) +r_base = . + /* Get our own relocated address */ + call 1f +1: popl %ebx + subl $1b, %ebx + + /* Compute the equivalent real-mode segment */ + movl %ebx, %ecx + shrl $4, %ecx + + /* Patch post-real-mode segment jump */ + movw dispatch_table(%ebx,%eax,2),%ax + movw %ax, 101f(%ebx) + movw %cx, 102f(%ebx) + + /* Set up the IDT for real mode. */ + lidtl machine_real_restart_idt(%ebx) + + /* + * Set up a GDT from which we can load segment descriptors for real + * mode. The GDT is not used in real mode; it is just needed here to + * prepare the descriptors. + */ + lgdtl machine_real_restart_gdt(%ebx) + + /* + * Load the data segment registers with 16-bit compatible values + */ + movl $16, %ecx + movl %ecx, %ds + movl %ecx, %es + movl %ecx, %fs + movl %ecx, %gs + movl %ecx, %ss + ljmpl $8, $1f - r_base + +/* + * This is 16-bit protected mode code to disable paging and the cache, + * switch to real mode and jump to the BIOS reset code. + * + * The instruction that switches to real mode by writing to CR0 must be + * followed immediately by a far jump instruction, which set CS to a + * valid value for real mode, and flushes the prefetch queue to avoid + * running instructions that have already been decoded in protected + * mode. + * + * Clears all the flags except ET, especially PG (paging), PE + * (protected-mode enable) and TS (task switch for coprocessor state + * save). Flushes the TLB after paging has been disabled. Sets CD and + * NW, to disable the cache on a 486, and invalidates the cache. This + * is more like the state of a 486 after reset. I don't know if + * something else should be done for other chips. + * + * More could be done here to set up the registers as if a CPU reset had + * occurred; hopefully real BIOSs don't assume much. This is not the + * actual BIOS entry point, anyway (that is at 0xfffffff0). + * + * Most of this work is probably excessive, but it is what is tested. + */ + .code16 +1: + xorl %ecx, %ecx + movl %cr0, %eax + andl $0x00000011, %eax + orl $0x60000000, %eax + movl %eax, %cr0 + movl %ecx, %cr3 + movl %cr0, %edx + andl $0x60000000, %edx /* If no cache bits -> no wbinvd */ + jz 2f + wbinvd +2: + andb $0x10, %al + movl %eax, %cr0 + .byte 0xea /* ljmpw */ +101: .word 0 /* Offset */ +102: .word 0 /* Segment */ + +bios: + ljmpw $0xf000, $0xfff0 + +apm: + movw $0x1000, %ax + movw %ax, %ss + movw $0xf000, %sp + movw $0x5307, %ax + movw $0x0001, %bx + movw $0x0003, %cx + int $0x15 + +END(machine_real_restart_asm) + + .balign 16 + /* These must match <asm/reboot.h */ +dispatch_table: + .word bios - r_base + .word apm - r_base +END(dispatch_table) + + .balign 16 +machine_real_restart_idt: + .word 0xffff /* Length - real mode default value */ + .long 0 /* Base - real mode default value */ +END(machine_real_restart_idt) + + .balign 16 +ENTRY(machine_real_restart_gdt) + .quad 0 /* Self-pointer, filled in by PM code */ + .quad 0 /* 16-bit code segment, filled in by PM code */ + /* + * 16-bit data segment with the selector value 16 = 0x10 and + * base value 0x100; since this is consistent with real mode + * semantics we don't have to reload the segments once CR0.PE = 0. + */ + .quad GDT_ENTRY(0x0093, 0x100, 0xffff) +END(machine_real_restart_gdt) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index b176f2b..9d43b28 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -963,15 +963,8 @@ void __init setup_arch(char **cmdline_p) printk(KERN_DEBUG "initial memory mapped : 0 - %08lx\n", max_pfn_mapped<<PAGE_SHIFT); - reserve_trampoline_memory(); + setup_trampolines(); -#ifdef CONFIG_ACPI_SLEEP - /* - * Reserve low memory region for sleep support. - * even before init_memory_mapping - */ - acpi_reserve_wakeup_memory(); -#endif init_gbpages(); /* max_pfn_mapped is updated here */ diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index e9efdfd..c2871d3 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -711,7 +711,7 @@ do_rest: stack_start = c_idle.idle->thread.sp; /* start_ip had better be page-aligned! */ - start_ip = setup_trampoline(); + start_ip = trampoline_address(); /* So we see what's up */ announce_cpu(cpu, apicid); @@ -721,6 +721,8 @@ do_rest: * the targeted processor. */ + printk(KERN_DEBUG "smpboot cpu %d: start_ip = %lx\n", cpu, start_ip); + atomic_set(&init_deasserted, 0); if (get_uv_system_type() != UV_NON_UNIQUE_APIC) { @@ -774,8 +776,8 @@ do_rest: pr_debug("CPU%d: has booted.\n", cpu); else { boot_error = 1; - if (*((volatile unsigned char *)trampoline_base) - == 0xA5) + if (*(volatile u32 *)TRAMPOLINE_SYM(trampoline_status) + == 0xA5A5A5A5) /* trampoline started but...? */ pr_err("CPU%d: Stuck ??\n", cpu); else @@ -801,7 +803,7 @@ do_rest: } /* mark "stuck" area as not stuck */ - *((volatile unsigned long *)trampoline_base) = 0; + *(volatile u32 *)TRAMPOLINE_SYM(trampoline_status) = 0; if (get_uv_system_type() != UV_NON_UNIQUE_APIC) { /* diff --git a/arch/x86/kernel/trampoline.c b/arch/x86/kernel/trampoline.c index a375616..a91ae77 100644 --- a/arch/x86/kernel/trampoline.c +++ b/arch/x86/kernel/trampoline.c @@ -2,39 +2,41 @@ #include <linux/memblock.h> #include <asm/trampoline.h> +#include <asm/cacheflush.h> #include <asm/pgtable.h> -#if defined(CONFIG_X86_64) && defined(CONFIG_ACPI_SLEEP) -#define __trampinit -#define __trampinitdata -#else -#define __trampinit __cpuinit -#define __trampinitdata __cpuinitdata -#endif +unsigned char *x86_trampoline_base; -/* ready for x86_64 and x86 */ -unsigned char *__trampinitdata trampoline_base; - -void __init reserve_trampoline_memory(void) +void __init setup_trampolines(void) { phys_addr_t mem; + size_t size = PAGE_ALIGN(x86_trampoline_end - x86_trampoline_start); /* Has to be in very low memory so we can execute real-mode AP code. */ - mem = memblock_find_in_range(0, 1<<20, TRAMPOLINE_SIZE, PAGE_SIZE); + mem = memblock_find_in_range(0, 1<<20, size, PAGE_SIZE); if (mem == MEMBLOCK_ERROR) panic("Cannot allocate trampoline\n"); - trampoline_base = __va(mem); - memblock_x86_reserve_range(mem, mem + TRAMPOLINE_SIZE, "TRAMPOLINE"); + x86_trampoline_base = __va(mem); + memblock_x86_reserve_range(mem, mem + size, "TRAMPOLINE"); + + printk(KERN_DEBUG "Base memory trampoline at [%p] %llx size %zu\n", + x86_trampoline_base, (unsigned long long)mem, size); + + memcpy(x86_trampoline_base, x86_trampoline_start, size); } /* - * Currently trivial. Write the real->protected mode - * bootstrap into the page concerned. The caller - * has made sure it's suitably aligned. + * setup_trampolines() gets called very early, to guarantee the + * availability of low memory. This is before the proper kernel page + * tables are set up, so we cannot set page permissions in that + * function. Thus, we use an arch_initcall instead. */ -unsigned long __trampinit setup_trampoline(void) +static int __init configure_trampolines(void) { - memcpy(trampoline_base, trampoline_data, TRAMPOLINE_SIZE); - return virt_to_phys(trampoline_base); + size_t size = PAGE_ALIGN(x86_trampoline_end - x86_trampoline_start); + + set_memory_x((unsigned long)x86_trampoline_base, size >> PAGE_SHIFT); + return 0; } +arch_initcall(configure_trampolines); diff --git a/arch/x86/kernel/trampoline_32.S b/arch/x86/kernel/trampoline_32.S index 8508237..451c0a7 100644 --- a/arch/x86/kernel/trampoline_32.S +++ b/arch/x86/kernel/trampoline_32.S @@ -32,9 +32,11 @@ #include <asm/segment.h> #include <asm/page_types.h> -/* We can free up trampoline after bootup if cpu hotplug is not supported. */ -__CPUINITRODATA -.code16 +#ifdef CONFIG_SMP + + .section ".x86_trampoline","a" + .balign PAGE_SIZE + .code16 ENTRY(trampoline_data) r_base = . @@ -44,7 +46,7 @@ r_base = . cli # We should be safe anyway - movl $0xA5A5A5A5, trampoline_data - r_base + movl $0xA5A5A5A5, trampoline_status - r_base # write marker for master knows we're running /* GDT tables in non default location kernel can be beyond 16MB and @@ -72,5 +74,10 @@ boot_idt_descr: .word 0 # idt limit = 0 .long 0 # idt base = 0L +ENTRY(trampoline_status) + .long 0 + .globl trampoline_end trampoline_end: + +#endif /* CONFIG_SMP */ diff --git a/arch/x86/kernel/trampoline_64.S b/arch/x86/kernel/trampoline_64.S index 075d130..09ff517 100644 --- a/arch/x86/kernel/trampoline_64.S +++ b/arch/x86/kernel/trampoline_64.S @@ -32,13 +32,9 @@ #include <asm/segment.h> #include <asm/processor-flags.h> -#ifdef CONFIG_ACPI_SLEEP -.section .rodata, "a", @progbits -#else -/* We can free up the trampoline after bootup if cpu hotplug is not supported. */ -__CPUINITRODATA -#endif -.code16 + .section ".x86_trampoline","a" + .balign PAGE_SIZE + .code16 ENTRY(trampoline_data) r_base = . @@ -50,7 +46,7 @@ r_base = . mov %ax, %ss - movl $0xA5A5A5A5, trampoline_data - r_base + movl $0xA5A5A5A5, trampoline_status - r_base # write marker for master knows we're running # Setup stack @@ -64,10 +60,13 @@ r_base = . movzx %ax, %esi # Find the 32bit trampoline location shll $4, %esi - # Fixup the vectors - addl %esi, startup_32_vector - r_base - addl %esi, startup_64_vector - r_base - addl %esi, tgdt + 2 - r_base # Fixup the gdt pointer + # Fixup the absolute vectors + leal (startup_32 - r_base)(%esi), %eax + movl %eax, startup_32_vector - r_base + leal (startup_64 - r_base)(%esi), %eax + movl %eax, startup_64_vector - r_base + leal (tgdt - r_base)(%esi), %eax + movl %eax, (tgdt + 2 - r_base) /* * GDT tables in non default location kernel can be beyond 16MB and @@ -129,6 +128,7 @@ no_longmode: jmp no_longmode #include "verify_cpu.S" + .balign 4 # Careful these need to be in the same 64K segment as the above; tidt: .word 0 # idt limit = 0 @@ -156,6 +156,10 @@ startup_64_vector: .long startup_64 - r_base .word __KERNEL_CS, 0 + .balign 4 +ENTRY(trampoline_status) + .long 0 + trampoline_stack: .org 0x1000 trampoline_stack_end: diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index 101c323..624a201 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -241,6 +241,18 @@ SECTIONS INIT_DATA_SECTION(16) + /* + * Code and data for a variety of lowlevel trampolines, to be + * copied into base memory (< 1 MiB) during initialization. + * Since it is copied early, the main copy can be discarded + * afterwards. + */ + .x86_trampoline : AT(ADDR(.x86_trampoline) - LOAD_OFFSET) { + x86_trampoline_start = .; + *(.x86_trampoline) + x86_trampoline_end = .; + } + .x86_cpu_dev.init : AT(ADDR(.x86_cpu_dev.init) - LOAD_OFFSET) { __x86_cpu_dev_start = .; *(.x86_cpu_dev.init) @@ -292,6 +304,7 @@ SECTIONS *(.iommu_table) __iommu_table_end = .; } + . = ALIGN(8); /* * .exit.text is discard at runtime, not link time, to deal with |