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-rw-r--r--arch/x86/boot/Makefile2
-rw-r--r--arch/x86/boot/boot.h10
-rw-r--r--arch/x86/boot/compressed/Makefile2
-rw-r--r--arch/x86/boot/compressed/aslr.c316
-rw-r--r--arch/x86/boot/compressed/cmdline.c2
-rw-r--r--arch/x86/boot/compressed/cpuflags.c12
-rw-r--r--arch/x86/boot/compressed/head_32.S10
-rw-r--r--arch/x86/boot/compressed/head_64.S16
-rw-r--r--arch/x86/boot/compressed/misc.c18
-rw-r--r--arch/x86/boot/compressed/misc.h37
-rw-r--r--arch/x86/boot/cpucheck.c100
-rw-r--r--arch/x86/boot/cpuflags.c104
-rw-r--r--arch/x86/boot/cpuflags.h19
-rw-r--r--arch/x86/boot/header.S9
14 files changed, 525 insertions, 132 deletions
diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile
index 7c2b0a18a6e..878df7e88cd 100644
--- a/arch/x86/boot/Makefile
+++ b/arch/x86/boot/Makefile
@@ -20,7 +20,7 @@ targets := vmlinux.bin setup.bin setup.elf bzImage
targets += fdimage fdimage144 fdimage288 image.iso mtools.conf
subdir- := compressed
-setup-y += a20.o bioscall.o cmdline.o copy.o cpu.o cpucheck.o
+setup-y += a20.o bioscall.o cmdline.o copy.o cpu.o cpuflags.o cpucheck.o
setup-y += early_serial_console.o edd.o header.o main.o mca.o memory.o
setup-y += pm.o pmjump.o printf.o regs.o string.o tty.o video.o
setup-y += video-mode.o version.o
diff --git a/arch/x86/boot/boot.h b/arch/x86/boot/boot.h
index ef72baeff48..50f8c5e0f37 100644
--- a/arch/x86/boot/boot.h
+++ b/arch/x86/boot/boot.h
@@ -26,9 +26,8 @@
#include <asm/boot.h>
#include <asm/setup.h>
#include "bitops.h"
-#include <asm/cpufeature.h>
-#include <asm/processor-flags.h>
#include "ctype.h"
+#include "cpuflags.h"
/* Useful macros */
#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
@@ -307,14 +306,7 @@ static inline int cmdline_find_option_bool(const char *option)
return __cmdline_find_option_bool(cmd_line_ptr, option);
}
-
/* cpu.c, cpucheck.c */
-struct cpu_features {
- int level; /* Family, or 64 for x86-64 */
- int model;
- u32 flags[NCAPINTS];
-};
-extern struct cpu_features cpu;
int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr);
int validate_cpu(void);
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index c8a6792e784..0fcd9133790 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -28,7 +28,7 @@ HOST_EXTRACFLAGS += -I$(srctree)/tools/include
VMLINUX_OBJS = $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o \
$(obj)/string.o $(obj)/cmdline.o $(obj)/early_serial_console.o \
- $(obj)/piggy.o
+ $(obj)/piggy.o $(obj)/cpuflags.o $(obj)/aslr.o
$(obj)/eboot.o: KBUILD_CFLAGS += -fshort-wchar -mno-red-zone
diff --git a/arch/x86/boot/compressed/aslr.c b/arch/x86/boot/compressed/aslr.c
new file mode 100644
index 00000000000..90a21f43011
--- /dev/null
+++ b/arch/x86/boot/compressed/aslr.c
@@ -0,0 +1,316 @@
+#include "misc.h"
+
+#ifdef CONFIG_RANDOMIZE_BASE
+#include <asm/msr.h>
+#include <asm/archrandom.h>
+#include <asm/e820.h>
+
+#include <generated/compile.h>
+#include <linux/module.h>
+#include <linux/uts.h>
+#include <linux/utsname.h>
+#include <generated/utsrelease.h>
+
+/* Simplified build-specific string for starting entropy. */
+static const char build_str[] = UTS_RELEASE " (" LINUX_COMPILE_BY "@"
+ LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION;
+
+#define I8254_PORT_CONTROL 0x43
+#define I8254_PORT_COUNTER0 0x40
+#define I8254_CMD_READBACK 0xC0
+#define I8254_SELECT_COUNTER0 0x02
+#define I8254_STATUS_NOTREADY 0x40
+static inline u16 i8254(void)
+{
+ u16 status, timer;
+
+ do {
+ outb(I8254_PORT_CONTROL,
+ I8254_CMD_READBACK | I8254_SELECT_COUNTER0);
+ status = inb(I8254_PORT_COUNTER0);
+ timer = inb(I8254_PORT_COUNTER0);
+ timer |= inb(I8254_PORT_COUNTER0) << 8;
+ } while (status & I8254_STATUS_NOTREADY);
+
+ return timer;
+}
+
+static unsigned long rotate_xor(unsigned long hash, const void *area,
+ size_t size)
+{
+ size_t i;
+ unsigned long *ptr = (unsigned long *)area;
+
+ for (i = 0; i < size / sizeof(hash); i++) {
+ /* Rotate by odd number of bits and XOR. */
+ hash = (hash << ((sizeof(hash) * 8) - 7)) | (hash >> 7);
+ hash ^= ptr[i];
+ }
+
+ return hash;
+}
+
+/* Attempt to create a simple but unpredictable starting entropy. */
+static unsigned long get_random_boot(void)
+{
+ unsigned long hash = 0;
+
+ hash = rotate_xor(hash, build_str, sizeof(build_str));
+ hash = rotate_xor(hash, real_mode, sizeof(*real_mode));
+
+ return hash;
+}
+
+static unsigned long get_random_long(void)
+{
+#ifdef CONFIG_X86_64
+ const unsigned long mix_const = 0x5d6008cbf3848dd3UL;
+#else
+ const unsigned long mix_const = 0x3f39e593UL;
+#endif
+ unsigned long raw, random = get_random_boot();
+ bool use_i8254 = true;
+
+ debug_putstr("KASLR using");
+
+ if (has_cpuflag(X86_FEATURE_RDRAND)) {
+ debug_putstr(" RDRAND");
+ if (rdrand_long(&raw)) {
+ random ^= raw;
+ use_i8254 = false;
+ }
+ }
+
+ if (has_cpuflag(X86_FEATURE_TSC)) {
+ debug_putstr(" RDTSC");
+ rdtscll(raw);
+
+ random ^= raw;
+ use_i8254 = false;
+ }
+
+ if (use_i8254) {
+ debug_putstr(" i8254");
+ random ^= i8254();
+ }
+
+ /* Circular multiply for better bit diffusion */
+ asm("mul %3"
+ : "=a" (random), "=d" (raw)
+ : "a" (random), "rm" (mix_const));
+ random += raw;
+
+ debug_putstr("...\n");
+
+ return random;
+}
+
+struct mem_vector {
+ unsigned long start;
+ unsigned long size;
+};
+
+#define MEM_AVOID_MAX 5
+struct mem_vector mem_avoid[MEM_AVOID_MAX];
+
+static bool mem_contains(struct mem_vector *region, struct mem_vector *item)
+{
+ /* Item at least partially before region. */
+ if (item->start < region->start)
+ return false;
+ /* Item at least partially after region. */
+ if (item->start + item->size > region->start + region->size)
+ return false;
+ return true;
+}
+
+static bool mem_overlaps(struct mem_vector *one, struct mem_vector *two)
+{
+ /* Item one is entirely before item two. */
+ if (one->start + one->size <= two->start)
+ return false;
+ /* Item one is entirely after item two. */
+ if (one->start >= two->start + two->size)
+ return false;
+ return true;
+}
+
+static void mem_avoid_init(unsigned long input, unsigned long input_size,
+ unsigned long output, unsigned long output_size)
+{
+ u64 initrd_start, initrd_size;
+ u64 cmd_line, cmd_line_size;
+ unsigned long unsafe, unsafe_len;
+ char *ptr;
+
+ /*
+ * Avoid the region that is unsafe to overlap during
+ * decompression (see calculations at top of misc.c).
+ */
+ unsafe_len = (output_size >> 12) + 32768 + 18;
+ unsafe = (unsigned long)input + input_size - unsafe_len;
+ mem_avoid[0].start = unsafe;
+ mem_avoid[0].size = unsafe_len;
+
+ /* Avoid initrd. */
+ initrd_start = (u64)real_mode->ext_ramdisk_image << 32;
+ initrd_start |= real_mode->hdr.ramdisk_image;
+ initrd_size = (u64)real_mode->ext_ramdisk_size << 32;
+ initrd_size |= real_mode->hdr.ramdisk_size;
+ mem_avoid[1].start = initrd_start;
+ mem_avoid[1].size = initrd_size;
+
+ /* Avoid kernel command line. */
+ cmd_line = (u64)real_mode->ext_cmd_line_ptr << 32;
+ cmd_line |= real_mode->hdr.cmd_line_ptr;
+ /* Calculate size of cmd_line. */
+ ptr = (char *)(unsigned long)cmd_line;
+ for (cmd_line_size = 0; ptr[cmd_line_size++]; )
+ ;
+ mem_avoid[2].start = cmd_line;
+ mem_avoid[2].size = cmd_line_size;
+
+ /* Avoid heap memory. */
+ mem_avoid[3].start = (unsigned long)free_mem_ptr;
+ mem_avoid[3].size = BOOT_HEAP_SIZE;
+
+ /* Avoid stack memory. */
+ mem_avoid[4].start = (unsigned long)free_mem_end_ptr;
+ mem_avoid[4].size = BOOT_STACK_SIZE;
+}
+
+/* Does this memory vector overlap a known avoided area? */
+bool mem_avoid_overlap(struct mem_vector *img)
+{
+ int i;
+
+ for (i = 0; i < MEM_AVOID_MAX; i++) {
+ if (mem_overlaps(img, &mem_avoid[i]))
+ return true;
+ }
+
+ return false;
+}
+
+unsigned long slots[CONFIG_RANDOMIZE_BASE_MAX_OFFSET / CONFIG_PHYSICAL_ALIGN];
+unsigned long slot_max = 0;
+
+static void slots_append(unsigned long addr)
+{
+ /* Overflowing the slots list should be impossible. */
+ if (slot_max >= CONFIG_RANDOMIZE_BASE_MAX_OFFSET /
+ CONFIG_PHYSICAL_ALIGN)
+ return;
+
+ slots[slot_max++] = addr;
+}
+
+static unsigned long slots_fetch_random(void)
+{
+ /* Handle case of no slots stored. */
+ if (slot_max == 0)
+ return 0;
+
+ return slots[get_random_long() % slot_max];
+}
+
+static void process_e820_entry(struct e820entry *entry,
+ unsigned long minimum,
+ unsigned long image_size)
+{
+ struct mem_vector region, img;
+
+ /* Skip non-RAM entries. */
+ if (entry->type != E820_RAM)
+ return;
+
+ /* Ignore entries entirely above our maximum. */
+ if (entry->addr >= CONFIG_RANDOMIZE_BASE_MAX_OFFSET)
+ return;
+
+ /* Ignore entries entirely below our minimum. */
+ if (entry->addr + entry->size < minimum)
+ return;
+
+ region.start = entry->addr;
+ region.size = entry->size;
+
+ /* Potentially raise address to minimum location. */
+ if (region.start < minimum)
+ region.start = minimum;
+
+ /* Potentially raise address to meet alignment requirements. */
+ region.start = ALIGN(region.start, CONFIG_PHYSICAL_ALIGN);
+
+ /* Did we raise the address above the bounds of this e820 region? */
+ if (region.start > entry->addr + entry->size)
+ return;
+
+ /* Reduce size by any delta from the original address. */
+ region.size -= region.start - entry->addr;
+
+ /* Reduce maximum size to fit end of image within maximum limit. */
+ if (region.start + region.size > CONFIG_RANDOMIZE_BASE_MAX_OFFSET)
+ region.size = CONFIG_RANDOMIZE_BASE_MAX_OFFSET - region.start;
+
+ /* Walk each aligned slot and check for avoided areas. */
+ for (img.start = region.start, img.size = image_size ;
+ mem_contains(&region, &img) ;
+ img.start += CONFIG_PHYSICAL_ALIGN) {
+ if (mem_avoid_overlap(&img))
+ continue;
+ slots_append(img.start);
+ }
+}
+
+static unsigned long find_random_addr(unsigned long minimum,
+ unsigned long size)
+{
+ int i;
+ unsigned long addr;
+
+ /* Make sure minimum is aligned. */
+ minimum = ALIGN(minimum, CONFIG_PHYSICAL_ALIGN);
+
+ /* Verify potential e820 positions, appending to slots list. */
+ for (i = 0; i < real_mode->e820_entries; i++) {
+ process_e820_entry(&real_mode->e820_map[i], minimum, size);
+ }
+
+ return slots_fetch_random();
+}
+
+unsigned char *choose_kernel_location(unsigned char *input,
+ unsigned long input_size,
+ unsigned char *output,
+ unsigned long output_size)
+{
+ unsigned long choice = (unsigned long)output;
+ unsigned long random;
+
+ if (cmdline_find_option_bool("nokaslr")) {
+ debug_putstr("KASLR disabled...\n");
+ goto out;
+ }
+
+ /* Record the various known unsafe memory ranges. */
+ mem_avoid_init((unsigned long)input, input_size,
+ (unsigned long)output, output_size);
+
+ /* Walk e820 and find a random address. */
+ random = find_random_addr(choice, output_size);
+ if (!random) {
+ debug_putstr("KASLR could not find suitable E820 region...\n");
+ goto out;
+ }
+
+ /* Always enforce the minimum. */
+ if (random < choice)
+ goto out;
+
+ choice = random;
+out:
+ return (unsigned char *)choice;
+}
+
+#endif /* CONFIG_RANDOMIZE_BASE */
diff --git a/arch/x86/boot/compressed/cmdline.c b/arch/x86/boot/compressed/cmdline.c
index bffd73b45b1..b68e3033e6b 100644
--- a/arch/x86/boot/compressed/cmdline.c
+++ b/arch/x86/boot/compressed/cmdline.c
@@ -1,6 +1,6 @@
#include "misc.h"
-#ifdef CONFIG_EARLY_PRINTK
+#if CONFIG_EARLY_PRINTK || CONFIG_RANDOMIZE_BASE
static unsigned long fs;
static inline void set_fs(unsigned long seg)
diff --git a/arch/x86/boot/compressed/cpuflags.c b/arch/x86/boot/compressed/cpuflags.c
new file mode 100644
index 00000000000..aa313466118
--- /dev/null
+++ b/arch/x86/boot/compressed/cpuflags.c
@@ -0,0 +1,12 @@
+#ifdef CONFIG_RANDOMIZE_BASE
+
+#include "../cpuflags.c"
+
+bool has_cpuflag(int flag)
+{
+ get_cpuflags();
+
+ return test_bit(flag, cpu.flags);
+}
+
+#endif
diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S
index 5d6f6891b18..9116aac232c 100644
--- a/arch/x86/boot/compressed/head_32.S
+++ b/arch/x86/boot/compressed/head_32.S
@@ -117,9 +117,11 @@ preferred_addr:
addl %eax, %ebx
notl %eax
andl %eax, %ebx
-#else
- movl $LOAD_PHYSICAL_ADDR, %ebx
+ cmpl $LOAD_PHYSICAL_ADDR, %ebx
+ jge 1f
#endif
+ movl $LOAD_PHYSICAL_ADDR, %ebx
+1:
/* Target address to relocate to for decompression */
addl $z_extract_offset, %ebx
@@ -191,14 +193,14 @@ relocated:
leal boot_heap(%ebx), %eax
pushl %eax /* heap area */
pushl %esi /* real mode pointer */
- call decompress_kernel
+ call decompress_kernel /* returns kernel location in %eax */
addl $24, %esp
/*
* Jump to the decompressed kernel.
*/
xorl %ebx, %ebx
- jmp *%ebp
+ jmp *%eax
/*
* Stack and heap for uncompression
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index c337422b575..c5c1ae0997e 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -94,9 +94,11 @@ ENTRY(startup_32)
addl %eax, %ebx
notl %eax
andl %eax, %ebx
-#else
- movl $LOAD_PHYSICAL_ADDR, %ebx
+ cmpl $LOAD_PHYSICAL_ADDR, %ebx
+ jge 1f
#endif
+ movl $LOAD_PHYSICAL_ADDR, %ebx
+1:
/* Target address to relocate to for decompression */
addl $z_extract_offset, %ebx
@@ -269,9 +271,11 @@ preferred_addr:
addq %rax, %rbp
notq %rax
andq %rax, %rbp
-#else
- movq $LOAD_PHYSICAL_ADDR, %rbp
+ cmpq $LOAD_PHYSICAL_ADDR, %rbp
+ jge 1f
#endif
+ movq $LOAD_PHYSICAL_ADDR, %rbp
+1:
/* Target address to relocate to for decompression */
leaq z_extract_offset(%rbp), %rbx
@@ -339,13 +343,13 @@ relocated:
movl $z_input_len, %ecx /* input_len */
movq %rbp, %r8 /* output target address */
movq $z_output_len, %r9 /* decompressed length */
- call decompress_kernel
+ call decompress_kernel /* returns kernel location in %rax */
popq %rsi
/*
* Jump to the decompressed kernel.
*/
- jmp *%rbp
+ jmp *%rax
.code32
no_longmode:
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index 434f077d2c4..196eaf373a0 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -112,14 +112,8 @@ struct boot_params *real_mode; /* Pointer to real-mode data */
void *memset(void *s, int c, size_t n);
void *memcpy(void *dest, const void *src, size_t n);
-#ifdef CONFIG_X86_64
-#define memptr long
-#else
-#define memptr unsigned
-#endif
-
-static memptr free_mem_ptr;
-static memptr free_mem_end_ptr;
+memptr free_mem_ptr;
+memptr free_mem_end_ptr;
static char *vidmem;
static int vidport;
@@ -395,7 +389,7 @@ static void parse_elf(void *output)
free(phdrs);
}
-asmlinkage void decompress_kernel(void *rmode, memptr heap,
+asmlinkage void *decompress_kernel(void *rmode, memptr heap,
unsigned char *input_data,
unsigned long input_len,
unsigned char *output,
@@ -422,6 +416,10 @@ asmlinkage void decompress_kernel(void *rmode, memptr heap,
free_mem_ptr = heap; /* Heap */
free_mem_end_ptr = heap + BOOT_HEAP_SIZE;
+ output = choose_kernel_location(input_data, input_len,
+ output, output_len);
+
+ /* Validate memory location choices. */
if ((unsigned long)output & (MIN_KERNEL_ALIGN - 1))
error("Destination address inappropriately aligned");
#ifdef CONFIG_X86_64
@@ -441,5 +439,5 @@ asmlinkage void decompress_kernel(void *rmode, memptr heap,
parse_elf(output);
handle_relocations(output, output_len);
debug_putstr("done.\nBooting the kernel.\n");
- return;
+ return output;
}
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 674019d8e23..24e3e569a13 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -23,7 +23,15 @@
#define BOOT_BOOT_H
#include "../ctype.h"
+#ifdef CONFIG_X86_64
+#define memptr long
+#else
+#define memptr unsigned
+#endif
+
/* misc.c */
+extern memptr free_mem_ptr;
+extern memptr free_mem_end_ptr;
extern struct boot_params *real_mode; /* Pointer to real-mode data */
void __putstr(const char *s);
#define error_putstr(__x) __putstr(__x)
@@ -39,23 +47,40 @@ static inline void debug_putstr(const char *s)
#endif
-#ifdef CONFIG_EARLY_PRINTK
-
+#if CONFIG_EARLY_PRINTK || CONFIG_RANDOMIZE_BASE
/* cmdline.c */
int cmdline_find_option(const char *option, char *buffer, int bufsize);
int cmdline_find_option_bool(const char *option);
+#endif
-/* early_serial_console.c */
-extern int early_serial_base;
-void console_init(void);
+#if CONFIG_RANDOMIZE_BASE
+/* aslr.c */
+unsigned char *choose_kernel_location(unsigned char *input,
+ unsigned long input_size,
+ unsigned char *output,
+ unsigned long output_size);
+/* cpuflags.c */
+bool has_cpuflag(int flag);
#else
+static inline
+unsigned char *choose_kernel_location(unsigned char *input,
+ unsigned long input_size,
+ unsigned char *output,
+ unsigned long output_size)
+{
+ return output;
+}
+#endif
+#ifdef CONFIG_EARLY_PRINTK
/* early_serial_console.c */
+extern int early_serial_base;
+void console_init(void);
+#else
static const int early_serial_base;
static inline void console_init(void)
{ }
-
#endif
#endif
diff --git a/arch/x86/boot/cpucheck.c b/arch/x86/boot/cpucheck.c
index 4d3ff037201..100a9a10076 100644
--- a/arch/x86/boot/cpucheck.c
+++ b/arch/x86/boot/cpucheck.c
@@ -28,8 +28,6 @@
#include <asm/required-features.h>
#include <asm/msr-index.h>
-struct cpu_features cpu;
-static u32 cpu_vendor[3];
static u32 err_flags[NCAPINTS];
static const int req_level = CONFIG_X86_MINIMUM_CPU_FAMILY;
@@ -69,92 +67,8 @@ static int is_transmeta(void)
cpu_vendor[2] == A32('M', 'x', '8', '6');
}
-static int has_fpu(void)
-{
- u16 fcw = -1, fsw = -1;
- u32 cr0;
-
- asm("movl %%cr0,%0" : "=r" (cr0));
- if (cr0 & (X86_CR0_EM|X86_CR0_TS)) {
- cr0 &= ~(X86_CR0_EM|X86_CR0_TS);
- asm volatile("movl %0,%%cr0" : : "r" (cr0));
- }
-
- asm volatile("fninit ; fnstsw %0 ; fnstcw %1"
- : "+m" (fsw), "+m" (fcw));
-
- return fsw == 0 && (fcw & 0x103f) == 0x003f;
-}
-
-static int has_eflag(u32 mask)
-{
- u32 f0, f1;
-
- asm("pushfl ; "
- "pushfl ; "
- "popl %0 ; "
- "movl %0,%1 ; "
- "xorl %2,%1 ; "
- "pushl %1 ; "
- "popfl ; "
- "pushfl ; "
- "popl %1 ; "
- "popfl"
- : "=&r" (f0), "=&r" (f1)
- : "ri" (mask));
-
- return !!((f0^f1) & mask);
-}
-
-static void get_flags(void)
-{
- u32 max_intel_level, max_amd_level;
- u32 tfms;
-
- if (has_fpu())
- set_bit(X86_FEATURE_FPU, cpu.flags);
-
- if (has_eflag(X86_EFLAGS_ID)) {
- asm("cpuid"
- : "=a" (max_intel_level),
- "=b" (cpu_vendor[0]),
- "=d" (cpu_vendor[1]),
- "=c" (cpu_vendor[2])
- : "a" (0));
-
- if (max_intel_level >= 0x00000001 &&
- max_intel_level <= 0x0000ffff) {
- asm("cpuid"
- : "=a" (tfms),
- "=c" (cpu.flags[4]),
- "=d" (cpu.flags[0])
- : "a" (0x00000001)
- : "ebx");
- cpu.level = (tfms >> 8) & 15;
- cpu.model = (tfms >> 4) & 15;
- if (cpu.level >= 6)
- cpu.model += ((tfms >> 16) & 0xf) << 4;
- }
-
- asm("cpuid"
- : "=a" (max_amd_level)
- : "a" (0x80000000)
- : "ebx", "ecx", "edx");
-
- if (max_amd_level >= 0x80000001 &&
- max_amd_level <= 0x8000ffff) {
- u32 eax = 0x80000001;
- asm("cpuid"
- : "+a" (eax),
- "=c" (cpu.flags[6]),
- "=d" (cpu.flags[1])
- : : "ebx");
- }
- }
-}
-
/* Returns a bitmask of which words we have error bits in */
-static int check_flags(void)
+static int check_cpuflags(void)
{
u32 err;
int i;
@@ -187,8 +101,8 @@ int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr)
if (has_eflag(X86_EFLAGS_AC))
cpu.level = 4;
- get_flags();
- err = check_flags();
+ get_cpuflags();
+ err = check_cpuflags();
if (test_bit(X86_FEATURE_LM, cpu.flags))
cpu.level = 64;
@@ -207,8 +121,8 @@ int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr)
eax &= ~(1 << 15);
asm("wrmsr" : : "a" (eax), "d" (edx), "c" (ecx));
- get_flags(); /* Make sure it really did something */
- err = check_flags();
+ get_cpuflags(); /* Make sure it really did something */
+ err = check_cpuflags();
} else if (err == 0x01 &&
!(err_flags[0] & ~(1 << X86_FEATURE_CX8)) &&
is_centaur() && cpu.model >= 6) {
@@ -223,7 +137,7 @@ int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr)
asm("wrmsr" : : "a" (eax), "d" (edx), "c" (ecx));
set_bit(X86_FEATURE_CX8, cpu.flags);
- err = check_flags();
+ err = check_cpuflags();
} else if (err == 0x01 && is_transmeta()) {
/* Transmeta might have masked feature bits in word 0 */
@@ -238,7 +152,7 @@ int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr)
: : "ecx", "ebx");
asm("wrmsr" : : "a" (eax), "d" (edx), "c" (ecx));
- err = check_flags();
+ err = check_cpuflags();
}
if (err_flags_ptr)
diff --git a/arch/x86/boot/cpuflags.c b/arch/x86/boot/cpuflags.c
new file mode 100644
index 00000000000..a9fcb7cfb24
--- /dev/null
+++ b/arch/x86/boot/cpuflags.c
@@ -0,0 +1,104 @@
+#include <linux/types.h>
+#include "bitops.h"
+
+#include <asm/processor-flags.h>
+#include <asm/required-features.h>
+#include <asm/msr-index.h>
+#include "cpuflags.h"
+
+struct cpu_features cpu;
+u32 cpu_vendor[3];
+
+static bool loaded_flags;
+
+static int has_fpu(void)
+{
+ u16 fcw = -1, fsw = -1;
+ unsigned long cr0;
+
+ asm volatile("mov %%cr0,%0" : "=r" (cr0));
+ if (cr0 & (X86_CR0_EM|X86_CR0_TS)) {
+ cr0 &= ~(X86_CR0_EM|X86_CR0_TS);
+ asm volatile("mov %0,%%cr0" : : "r" (cr0));
+ }
+
+ asm volatile("fninit ; fnstsw %0 ; fnstcw %1"
+ : "+m" (fsw), "+m" (fcw));
+
+ return fsw == 0 && (fcw & 0x103f) == 0x003f;
+}
+
+int has_eflag(unsigned long mask)
+{
+ unsigned long f0, f1;
+
+ asm volatile("pushf \n\t"
+ "pushf \n\t"
+ "pop %0 \n\t"
+ "mov %0,%1 \n\t"
+ "xor %2,%1 \n\t"
+ "push %1 \n\t"
+ "popf \n\t"
+ "pushf \n\t"
+ "pop %1 \n\t"
+ "popf"
+ : "=&r" (f0), "=&r" (f1)
+ : "ri" (mask));
+
+ return !!((f0^f1) & mask);
+}
+
+/* Handle x86_32 PIC using ebx. */
+#if defined(__i386__) && defined(__PIC__)
+# define EBX_REG "=r"
+#else
+# define EBX_REG "=b"
+#endif
+
+static inline void cpuid(u32 id, u32 *a, u32 *b, u32 *c, u32 *d)
+{
+ asm volatile(".ifnc %%ebx,%3 ; movl %%ebx,%3 ; .endif \n\t"
+ "cpuid \n\t"
+ ".ifnc %%ebx,%3 ; xchgl %%ebx,%3 ; .endif \n\t"
+ : "=a" (*a), "=c" (*c), "=d" (*d), EBX_REG (*b)
+ : "a" (id)
+ );
+}
+
+void get_cpuflags(void)
+{
+ u32 max_intel_level, max_amd_level;
+ u32 tfms;
+ u32 ignored;
+
+ if (loaded_flags)
+ return;
+ loaded_flags = true;
+
+ if (has_fpu())
+ set_bit(X86_FEATURE_FPU, cpu.flags);
+
+ if (has_eflag(X86_EFLAGS_ID)) {
+ cpuid(0x0, &max_intel_level, &cpu_vendor[0], &cpu_vendor[2],
+ &cpu_vendor[1]);
+
+ if (max_intel_level >= 0x00000001 &&
+ max_intel_level <= 0x0000ffff) {
+ cpuid(0x1, &tfms, &ignored, &cpu.flags[4],
+ &cpu.flags[0]);
+ cpu.level = (tfms >> 8) & 15;
+ cpu.model = (tfms >> 4) & 15;
+ if (cpu.level >= 6)
+ cpu.model += ((tfms >> 16) & 0xf) << 4;
+ }
+
+ cpuid(0x80000000, &max_amd_level, &ignored, &ignored,
+ &ignored);
+
+ if (max_amd_level >= 0x80000001 &&
+ max_amd_level <= 0x8000ffff) {
+ cpuid(0x80000001, &ignored, &ignored, &cpu.flags[6],
+ &cpu.flags[1]);
+ }
+ }
+}
diff --git a/arch/x86/boot/cpuflags.h b/arch/x86/boot/cpuflags.h
new file mode 100644
index 00000000000..ea97697e51e
--- /dev/null
+++ b/arch/x86/boot/cpuflags.h
@@ -0,0 +1,19 @@
+#ifndef BOOT_CPUFLAGS_H
+#define BOOT_CPUFLAGS_H
+
+#include <asm/cpufeature.h>
+#include <asm/processor-flags.h>
+
+struct cpu_features {
+ int level; /* Family, or 64 for x86-64 */
+ int model;
+ u32 flags[NCAPINTS];
+};
+
+extern struct cpu_features cpu;
+extern u32 cpu_vendor[3];
+
+int has_eflag(unsigned long mask);
+void get_cpuflags(void);
+
+#endif
diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index 9ec06a1f6d6..ec3b8ba6809 100644
--- a/arch/x86/boot/header.S
+++ b/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
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-29 18:16:10 +0000