lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

Browse Source 
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, cpu: Fix detection of Celeron Covington stepping A1 and B0
  Documentation, ABI: Update L3 cache index disable text
  x86, AMD, cacheinfo: Fix L3 cache index disable checks
  x86, AMD, cacheinfo: Fix fallout caused by max3 conversion
  x86, cpu: Change NOP selection for certain Intel CPUs
  x86, cpu: Clean up and unify the NOP selection infrastructure
  x86, percpu: Use ASM_NOP4 instead of hardcoding P6_NOP4
  x86, cpu: Move AMD Elan Kconfig under "Processor family"

Fix up trivial conflicts in alternative handling (commit dc326fca2b
"x86, cpu: Clean up and unify the NOP selection infrastructure" removed
some hacky 5-byte instruction stuff, while commit d430d3d7e6 "jump
label: Introduce static_branch() interface" renamed HAVE_JUMP_LABEL to
CONFIG_JUMP_LABEL in the code that went away)
This commit is contained in:
Linus Torvalds
2011-05-19 17:55:12 -07:00
parent 17b141803c 865be7a810
commit 0162818804
15 changed files with 242 additions and 222 deletions
Download Patch File Download Diff File Expand all files Collapse all files

196
arch/x86/kernel/alternative.c
View File

@ -67,17 +67,30 @@ __setup("noreplace-paravirt", setup_noreplace_paravirt);
#define DPRINTK(fmt, args...) if (debug_alternative) \
printk(KERN_DEBUG fmt, args)
/*
* Each GENERIC_NOPX is of X bytes, and defined as an array of bytes
* that correspond to that nop. Getting from one nop to the next, we
* add to the array the offset that is equal to the sum of all sizes of
* nops preceding the one we are after.
*
* Note: The GENERIC_NOP5_ATOMIC is at the end, as it breaks the
* nice symmetry of sizes of the previous nops.
*/
#if defined(GENERIC_NOP1) && !defined(CONFIG_X86_64)
/* Use inline assembly to define this because the nops are defined
as inline assembly strings in the include files and we cannot
get them easily into strings. */
asm("\t" __stringify(__INITRODATA_OR_MODULE) "\nintelnops: "
GENERIC_NOP1 GENERIC_NOP2 GENERIC_NOP3 GENERIC_NOP4 GENERIC_NOP5 GENERIC_NOP6
GENERIC_NOP7 GENERIC_NOP8
"\t.previous");
extern const unsigned char intelnops[];
static const unsigned char *const __initconst_or_module
intel_nops[ASM_NOP_MAX+1] = {
static const unsigned char intelnops[] =
{
GENERIC_NOP1,
GENERIC_NOP2,
GENERIC_NOP3,
GENERIC_NOP4,
GENERIC_NOP5,
GENERIC_NOP6,
GENERIC_NOP7,
GENERIC_NOP8,
GENERIC_NOP5_ATOMIC
};
static const unsigned char * const intel_nops[ASM_NOP_MAX+2] =
{
NULL,
intelnops,
intelnops + 1,
@ -87,17 +100,25 @@ intel_nops[ASM_NOP_MAX+1] = {
intelnops + 1 + 2 + 3 + 4 + 5,
intelnops + 1 + 2 + 3 + 4 + 5 + 6,
intelnops + 1 + 2 + 3 + 4 + 5 + 6 + 7,
intelnops + 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8,
};
#endif
#ifdef K8_NOP1
asm("\t" __stringify(__INITRODATA_OR_MODULE) "\nk8nops: "
K8_NOP1 K8_NOP2 K8_NOP3 K8_NOP4 K8_NOP5 K8_NOP6
K8_NOP7 K8_NOP8
"\t.previous");
extern const unsigned char k8nops[];
static const unsigned char *const __initconst_or_module
k8_nops[ASM_NOP_MAX+1] = {
static const unsigned char k8nops[] =
{
K8_NOP1,
K8_NOP2,
K8_NOP3,
K8_NOP4,
K8_NOP5,
K8_NOP6,
K8_NOP7,
K8_NOP8,
K8_NOP5_ATOMIC
};
static const unsigned char * const k8_nops[ASM_NOP_MAX+2] =
{
NULL,
k8nops,
k8nops + 1,
@ -107,17 +128,25 @@ k8_nops[ASM_NOP_MAX+1] = {
k8nops + 1 + 2 + 3 + 4 + 5,
k8nops + 1 + 2 + 3 + 4 + 5 + 6,
k8nops + 1 + 2 + 3 + 4 + 5 + 6 + 7,
k8nops + 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8,
};
#endif
#if defined(K7_NOP1) && !defined(CONFIG_X86_64)
asm("\t" __stringify(__INITRODATA_OR_MODULE) "\nk7nops: "
K7_NOP1 K7_NOP2 K7_NOP3 K7_NOP4 K7_NOP5 K7_NOP6
K7_NOP7 K7_NOP8
"\t.previous");
extern const unsigned char k7nops[];
static const unsigned char *const __initconst_or_module
k7_nops[ASM_NOP_MAX+1] = {
static const unsigned char k7nops[] =
{
K7_NOP1,
K7_NOP2,
K7_NOP3,
K7_NOP4,
K7_NOP5,
K7_NOP6,
K7_NOP7,
K7_NOP8,
K7_NOP5_ATOMIC
};
static const unsigned char * const k7_nops[ASM_NOP_MAX+2] =
{
NULL,
k7nops,
k7nops + 1,
@ -127,17 +156,25 @@ k7_nops[ASM_NOP_MAX+1] = {
k7nops + 1 + 2 + 3 + 4 + 5,
k7nops + 1 + 2 + 3 + 4 + 5 + 6,
k7nops + 1 + 2 + 3 + 4 + 5 + 6 + 7,
k7nops + 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8,
};
#endif
#ifdef P6_NOP1
asm("\t" __stringify(__INITRODATA_OR_MODULE) "\np6nops: "
P6_NOP1 P6_NOP2 P6_NOP3 P6_NOP4 P6_NOP5 P6_NOP6
P6_NOP7 P6_NOP8
"\t.previous");
extern const unsigned char p6nops[];
static const unsigned char *const __initconst_or_module
p6_nops[ASM_NOP_MAX+1] = {
static const unsigned char __initconst_or_module p6nops[] =
{
P6_NOP1,
P6_NOP2,
P6_NOP3,
P6_NOP4,
P6_NOP5,
P6_NOP6,
P6_NOP7,
P6_NOP8,
P6_NOP5_ATOMIC
};
static const unsigned char * const p6_nops[ASM_NOP_MAX+2] =
{
NULL,
p6nops,
p6nops + 1,
@ -147,47 +184,65 @@ p6_nops[ASM_NOP_MAX+1] = {
p6nops + 1 + 2 + 3 + 4 + 5,
p6nops + 1 + 2 + 3 + 4 + 5 + 6,
p6nops + 1 + 2 + 3 + 4 + 5 + 6 + 7,
p6nops + 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8,
};
#endif
/* Initialize these to a safe default */
#ifdef CONFIG_X86_64
const unsigned char * const *ideal_nops = p6_nops;
#else
const unsigned char * const *ideal_nops = intel_nops;
#endif
extern char __vsyscall_0;
static const unsigned char *const *__init_or_module find_nop_table(void)
void __init arch_init_ideal_nops(void)
{
if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
boot_cpu_has(X86_FEATURE_NOPL))
return p6_nops;
else
return k8_nops;
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_INTEL:
/*
* Due to a decoder implementation quirk, some
* specific Intel CPUs actually perform better with
* the "k8_nops" than with the SDM-recommended NOPs.
*/
if (boot_cpu_data.x86 == 6 &&
boot_cpu_data.x86_model >= 0x0f &&
boot_cpu_data.x86_model != 0x1c &&
boot_cpu_data.x86_model != 0x26 &&
boot_cpu_data.x86_model != 0x27 &&
boot_cpu_data.x86_model < 0x30) {
ideal_nops = k8_nops;
} else if (boot_cpu_has(X86_FEATURE_NOPL)) {
ideal_nops = p6_nops;
} else {
#ifdef CONFIG_X86_64
ideal_nops = k8_nops;
#else
ideal_nops = intel_nops;
#endif
}
default:
#ifdef CONFIG_X86_64
ideal_nops = k8_nops;
#else
if (boot_cpu_has(X86_FEATURE_K8))
ideal_nops = k8_nops;
else if (boot_cpu_has(X86_FEATURE_K7))
ideal_nops = k7_nops;
else
ideal_nops = intel_nops;
#endif
}
}
#else /* CONFIG_X86_64 */
static const unsigned char *const *__init_or_module find_nop_table(void)
{
if (boot_cpu_has(X86_FEATURE_K8))
return k8_nops;
else if (boot_cpu_has(X86_FEATURE_K7))
return k7_nops;
else if (boot_cpu_has(X86_FEATURE_NOPL))
return p6_nops;
else
return intel_nops;
}
#endif /* CONFIG_X86_64 */
/* Use this to add nops to a buffer, then text_poke the whole buffer. */
static void __init_or_module add_nops(void *insns, unsigned int len)
{
const unsigned char *const *noptable = find_nop_table();
while (len > 0) {
unsigned int noplen = len;
if (noplen > ASM_NOP_MAX)
noplen = ASM_NOP_MAX;
memcpy(insns, noptable[noplen], noplen);
memcpy(insns, ideal_nops[noplen], noplen);
insns += noplen;
len -= noplen;
}
@ -195,6 +250,7 @@ static void __init_or_module add_nops(void *insns, unsigned int len)
extern struct alt_instr __alt_instructions[], __alt_instructions_end[];
extern s32 __smp_locks[], __smp_locks_end[];
extern char __vsyscall_0;
void *text_poke_early(void *addr, const void *opcode, size_t len);
/* Replace instructions with better alternatives for this CPU type.
@ -687,29 +743,3 @@ void __kprobes text_poke_smp_batch(struct text_poke_param *params, int n)
wrote_text = 0;
__stop_machine(stop_machine_text_poke, (void *)&tpp, NULL);
}
#if defined(CONFIG_DYNAMIC_FTRACE) || defined(CONFIG_JUMP_LABEL)
#ifdef CONFIG_X86_64
unsigned char ideal_nop5[5] = { 0x66, 0x66, 0x66, 0x66, 0x90 };
#else
unsigned char ideal_nop5[5] = { 0x3e, 0x8d, 0x74, 0x26, 0x00 };
#endif
void __init arch_init_ideal_nop5(void)
{
/*
* There is no good nop for all x86 archs. This selection
* algorithm should be unified with the one in find_nop_table(),
* but this should be good enough for now.
*
* For cases other than the ones below, use the safe (as in
* always functional) defaults above.
*/
#ifdef CONFIG_X86_64
/* Don't use these on 32 bits due to broken virtualizers */
if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
memcpy(ideal_nop5, p6_nops[5], 5);
#endif
}
#endif