diff options
| -rw-r--r-- | arch/x86/include/asm/alternative.h | 8 | ||||
| -rw-r--r-- | arch/x86/include/asm/nops.h | 146 | ||||
| -rw-r--r-- | arch/x86/kernel/alternative.c | 182 | ||||
| -rw-r--r-- | arch/x86/kernel/ftrace.c | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/jump_label.c | 5 | ||||
| -rw-r--r-- | arch/x86/kernel/setup.c | 6 |
6 files changed, 190 insertions, 161 deletions
diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h index 13009d1af99a..7da168225a9d 100644 --- a/arch/x86/include/asm/alternative.h +++ b/arch/x86/include/asm/alternative.h @@ -191,12 +191,4 @@ extern void *text_poke(void *addr, const void *opcode, size_t len); extern void *text_poke_smp(void *addr, const void *opcode, size_t len); extern void text_poke_smp_batch(struct text_poke_param *params, int n); -#if defined(CONFIG_DYNAMIC_FTRACE) || defined(HAVE_JUMP_LABEL) -#define IDEAL_NOP_SIZE_5 5 -extern unsigned char ideal_nop5[IDEAL_NOP_SIZE_5]; -extern void arch_init_ideal_nop5(void); -#else -static inline void arch_init_ideal_nop5(void) {} -#endif - #endif /* _ASM_X86_ALTERNATIVE_H */ diff --git a/arch/x86/include/asm/nops.h b/arch/x86/include/asm/nops.h index af788496020b..405b4032a60b 100644 --- a/arch/x86/include/asm/nops.h +++ b/arch/x86/include/asm/nops.h @@ -1,7 +1,13 @@ #ifndef _ASM_X86_NOPS_H #define _ASM_X86_NOPS_H -/* Define nops for use with alternative() */ +/* + * Define nops for use with alternative() and for tracing. + * + * *_NOP5_ATOMIC must be a single instruction. + */ + +#define NOP_DS_PREFIX 0x3e /* generic versions from gas 1: nop @@ -13,14 +19,15 @@ 6: leal 0x00000000(%esi),%esi 7: leal 0x00000000(,%esi,1),%esi */ -#define GENERIC_NOP1 ".byte 0x90\n" -#define GENERIC_NOP2 ".byte 0x89,0xf6\n" -#define GENERIC_NOP3 ".byte 0x8d,0x76,0x00\n" -#define GENERIC_NOP4 ".byte 0x8d,0x74,0x26,0x00\n" -#define GENERIC_NOP5 GENERIC_NOP1 GENERIC_NOP4 -#define GENERIC_NOP6 ".byte 0x8d,0xb6,0x00,0x00,0x00,0x00\n" -#define GENERIC_NOP7 ".byte 0x8d,0xb4,0x26,0x00,0x00,0x00,0x00\n" -#define GENERIC_NOP8 GENERIC_NOP1 GENERIC_NOP7 +#define GENERIC_NOP1 0x90 +#define GENERIC_NOP2 0x89,0xf6 +#define GENERIC_NOP3 0x8d,0x76,0x00 +#define GENERIC_NOP4 0x8d,0x74,0x26,0x00 +#define GENERIC_NOP5 GENERIC_NOP1,GENERIC_NOP4 +#define GENERIC_NOP6 0x8d,0xb6,0x00,0x00,0x00,0x00 +#define GENERIC_NOP7 0x8d,0xb4,0x26,0x00,0x00,0x00,0x00 +#define GENERIC_NOP8 GENERIC_NOP1,GENERIC_NOP7 +#define GENERIC_NOP5_ATOMIC NOP_DS_PREFIX,GENERIC_NOP4 /* Opteron 64bit nops 1: nop @@ -29,13 +36,14 @@ 4: osp osp osp nop */ #define K8_NOP1 GENERIC_NOP1 -#define K8_NOP2 ".byte 0x66,0x90\n" -#define K8_NOP3 ".byte 0x66,0x66,0x90\n" -#define K8_NOP4 ".byte 0x66,0x66,0x66,0x90\n" -#define K8_NOP5 K8_NOP3 K8_NOP2 -#define K8_NOP6 K8_NOP3 K8_NOP3 -#define K8_NOP7 K8_NOP4 K8_NOP3 -#define K8_NOP8 K8_NOP4 K8_NOP4 +#define K8_NOP2 0x66,K8_NOP1 +#define K8_NOP3 0x66,K8_NOP2 +#define K8_NOP4 0x66,K8_NOP3 +#define K8_NOP5 K8_NOP3,K8_NOP2 +#define K8_NOP6 K8_NOP3,K8_NOP3 +#define K8_NOP7 K8_NOP4,K8_NOP3 +#define K8_NOP8 K8_NOP4,K8_NOP4 +#define K8_NOP5_ATOMIC 0x66,K8_NOP4 /* K7 nops uses eax dependencies (arbitrary choice) @@ -47,13 +55,14 @@ 7: leal 0x00000000(,%eax,1),%eax */ #define K7_NOP1 GENERIC_NOP1 -#define K7_NOP2 ".byte 0x8b,0xc0\n" -#define K7_NOP3 ".byte 0x8d,0x04,0x20\n" -#define K7_NOP4 ".byte 0x8d,0x44,0x20,0x00\n" -#define K7_NOP5 K7_NOP4 ASM_NOP1 -#define K7_NOP6 ".byte 0x8d,0x80,0,0,0,0\n" -#define K7_NOP7 ".byte 0x8D,0x04,0x05,0,0,0,0\n" -#define K7_NOP8 K7_NOP7 ASM_NOP1 +#define K7_NOP2 0x8b,0xc0 +#define K7_NOP3 0x8d,0x04,0x20 +#define K7_NOP4 0x8d,0x44,0x20,0x00 +#define K7_NOP5 K7_NOP4,K7_NOP1 +#define K7_NOP6 0x8d,0x80,0,0,0,0 +#define K7_NOP7 0x8D,0x04,0x05,0,0,0,0 +#define K7_NOP8 K7_NOP7,K7_NOP1 +#define K7_NOP5_ATOMIC NOP_DS_PREFIX,K7_NOP4 /* P6 nops uses eax dependencies (Intel-recommended choice) @@ -69,52 +78,65 @@ There is kernel code that depends on this. */ #define P6_NOP1 GENERIC_NOP1 -#define P6_NOP2 ".byte 0x66,0x90\n" -#define P6_NOP3 ".byte 0x0f,0x1f,0x00\n" -#define P6_NOP4 ".byte 0x0f,0x1f,0x40,0\n" -#define P6_NOP5 ".byte 0x0f,0x1f,0x44,0x00,0\n" -#define P6_NOP6 ".byte 0x66,0x0f,0x1f,0x44,0x00,0\n" -#define P6_NOP7 ".byte 0x0f,0x1f,0x80,0,0,0,0\n" -#define P6_NOP8 ".byte 0x0f,0x1f,0x84,0x00,0,0,0,0\n" +#define P6_NOP2 0x66,0x90 +#define P6_NOP3 0x0f,0x1f,0x00 +#define P6_NOP4 0x0f,0x1f,0x40,0 +#define P6_NOP5 0x0f,0x1f,0x44,0x00,0 +#define P6_NOP6 0x66,0x0f,0x1f,0x44,0x00,0 +#define P6_NOP7 0x0f,0x1f,0x80,0,0,0,0 +#define P6_NOP8 0x0f,0x1f,0x84,0x00,0,0,0,0 +#define P6_NOP5_ATOMIC P6_NOP5 + +#define _ASM_MK_NOP(x) ".byte " __stringify(x) "\n" #if defined(CONFIG_MK7) -#define ASM_NOP1 K7_NOP1 -#define ASM_NOP2 K7_NOP2 -#define ASM_NOP3 K7_NOP3 -#define ASM_NOP4 K7_NOP4 -#define ASM_NOP5 K7_NOP5 -#define ASM_NOP6 K7_NOP6 -#define ASM_NOP7 K7_NOP7 -#define ASM_NOP8 K7_NOP8 +#define ASM_NOP1 _ASM_MK_NOP(K7_NOP1) +#define ASM_NOP2 _ASM_MK_NOP(K7_NOP2) +#define ASM_NOP3 _ASM_MK_NOP(K7_NOP3) +#define ASM_NOP4 _ASM_MK_NOP(K7_NOP4) +#define ASM_NOP5 _ASM_MK_NOP(K7_NOP5) +#define ASM_NOP6 _ASM_MK_NOP(K7_NOP6) +#define ASM_NOP7 _ASM_MK_NOP(K7_NOP7) +#define ASM_NOP8 _ASM_MK_NOP(K7_NOP8) +#define ASM_NOP5_ATOMIC _ASM_MK_NOP(K7_NOP5_ATOMIC) #elif defined(CONFIG_X86_P6_NOP) -#define ASM_NOP1 P6_NOP1 -#define ASM_NOP2 P6_NOP2 -#define ASM_NOP3 P6_NOP3 -#define ASM_NOP4 P6_NOP4 -#define ASM_NOP5 P6_NOP5 -#define ASM_NOP6 P6_NOP6 -#define ASM_NOP7 P6_NOP7 -#define ASM_NOP8 P6_NOP8 +#define ASM_NOP1 _ASM_MK_NOP(P6_NOP1) +#define ASM_NOP2 _ASM_MK_NOP(P6_NOP2) +#define ASM_NOP3 _ASM_MK_NOP(P6_NOP3) +#define ASM_NOP4 _ASM_MK_NOP(P6_NOP4) +#define ASM_NOP5 _ASM_MK_NOP(P6_NOP5) +#define ASM_NOP6 _ASM_MK_NOP(P6_NOP6) +#define ASM_NOP7 _ASM_MK_NOP(P6_NOP7) +#define ASM_NOP8 _ASM_MK_NOP(P6_NOP8) +#define ASM_NOP5_ATOMIC _ASM_MK_NOP(P6_NOP5_ATOMIC) #elif defined(CONFIG_X86_64) -#define ASM_NOP1 K8_NOP1 -#define ASM_NOP2 K8_NOP2 -#define ASM_NOP3 K8_NOP3 -#define ASM_NOP4 K8_NOP4 -#define ASM_NOP5 K8_NOP5 -#define ASM_NOP6 K8_NOP6 -#define ASM_NOP7 K8_NOP7 -#define ASM_NOP8 K8_NOP8 +#define ASM_NOP1 _ASM_MK_NOP(K8_NOP1) +#define ASM_NOP2 _ASM_MK_NOP(K8_NOP2) +#define ASM_NOP3 _ASM_MK_NOP(K8_NOP3) +#define ASM_NOP4 _ASM_MK_NOP(K8_NOP4) +#define ASM_NOP5 _ASM_MK_NOP(K8_NOP5) +#define ASM_NOP6 _ASM_MK_NOP(K8_NOP6) +#define ASM_NOP7 _ASM_MK_NOP(K8_NOP7) +#define ASM_NOP8 _ASM_MK_NOP(K8_NOP8) +#define ASM_NOP5_ATOMIC _ASM_MK_NOP(K8_NOP5_ATOMIC) #else -#define ASM_NOP1 GENERIC_NOP1 -#define ASM_NOP2 GENERIC_NOP2 -#define ASM_NOP3 GENERIC_NOP3 -#define ASM_NOP4 GENERIC_NOP4 -#define ASM_NOP5 GENERIC_NOP5 -#define ASM_NOP6 GENERIC_NOP6 -#define ASM_NOP7 GENERIC_NOP7 -#define ASM_NOP8 GENERIC_NOP8 +#define ASM_NOP1 _ASM_MK_NOP(GENERIC_NOP1) +#define ASM_NOP2 _ASM_MK_NOP(GENERIC_NOP2) +#define ASM_NOP3 _ASM_MK_NOP(GENERIC_NOP3) +#define ASM_NOP4 _ASM_MK_NOP(GENERIC_NOP4) +#define ASM_NOP5 _ASM_MK_NOP(GENERIC_NOP5) +#define ASM_NOP6 _ASM_MK_NOP(GENERIC_NOP6) +#define ASM_NOP7 _ASM_MK_NOP(GENERIC_NOP7) +#define ASM_NOP8 _ASM_MK_NOP(GENERIC_NOP8) +#define ASM_NOP5_ATOMIC _ASM_MK_NOP(GENERIC_NOP5_ATOMIC) #endif #define ASM_NOP_MAX 8 +#define NOP_ATOMIC5 (ASM_NOP_MAX+1) /* Entry for the 5-byte atomic NOP */ + +#ifndef __ASSEMBLY__ +extern const unsigned char * const *ideal_nops; +extern void arch_init_ideal_nops(void); +#endif #endif /* _ASM_X86_NOPS_H */ diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 4a234677e213..846f61eb89c1 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -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 +184,53 @@ 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; -} - -#else /* CONFIG_X86_64 */ + switch (boot_cpu_data.x86_vendor) { + case X86_VENDOR_INTEL: + 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 + } -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; + 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 + } } -#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 +238,7 @@ 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. @@ -678,29 +722,3 @@ 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(HAVE_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 diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index a93742a57468..0ba15a6cc57e 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -260,9 +260,9 @@ do_ftrace_mod_code(unsigned long ip, void *new_code) return mod_code_status; } -static unsigned char *ftrace_nop_replace(void) +static const unsigned char *ftrace_nop_replace(void) { - return ideal_nop5; + return ideal_nops[NOP_ATOMIC5]; } static int diff --git a/arch/x86/kernel/jump_label.c b/arch/x86/kernel/jump_label.c index 961b6b30ba90..3fee346ef545 100644 --- a/arch/x86/kernel/jump_label.c +++ b/arch/x86/kernel/jump_label.c @@ -34,7 +34,7 @@ void arch_jump_label_transform(struct jump_entry *entry, code.offset = entry->target - (entry->code + JUMP_LABEL_NOP_SIZE); } else - memcpy(&code, ideal_nop5, JUMP_LABEL_NOP_SIZE); + memcpy(&code, ideal_nops[NOP_ATOMIC5], JUMP_LABEL_NOP_SIZE); get_online_cpus(); mutex_lock(&text_mutex); text_poke_smp((void *)entry->code, &code, JUMP_LABEL_NOP_SIZE); @@ -44,7 +44,8 @@ void arch_jump_label_transform(struct jump_entry *entry, void arch_jump_label_text_poke_early(jump_label_t addr) { - text_poke_early((void *)addr, ideal_nop5, JUMP_LABEL_NOP_SIZE); + text_poke_early((void *)addr, ideal_nops[NOP_ATOMIC5], + JUMP_LABEL_NOP_SIZE); } #endif diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 5a0484a95ad6..390a663894d8 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -691,8 +691,6 @@ early_param("reservelow", parse_reservelow); void __init setup_arch(char **cmdline_p) { - unsigned long flags; - #ifdef CONFIG_X86_32 memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data)); visws_early_detect(); @@ -1036,9 +1034,7 @@ void __init setup_arch(char **cmdline_p) mcheck_init(); - local_irq_save(flags); - arch_init_ideal_nop5(); - local_irq_restore(flags); + arch_init_ideal_nops(); } #ifdef CONFIG_X86_32 |