diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 7116fda7077f..06600cc9a26c 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1011,6 +1011,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted. parameter will force ia64_sal_cache_flush to call ia64_pal_cache_flush instead of SAL_CACHE_FLUSH. + forcepae [X86-32] + Forcefully enable Physical Address Extension (PAE). + Many Pentium M systems disable PAE but may have a + functionally usable PAE implementation. + Warning: use of this parameter will taint the kernel + and may cause unknown problems. + ftrace=[tracer] [FTRACE] will set and start the specified tracer as early as possible in order to facilitate early diff --git a/arch/x86/boot/cpucheck.c b/arch/x86/boot/cpucheck.c index 100a9a10076a..f0d0b20fe149 100644 --- a/arch/x86/boot/cpucheck.c +++ b/arch/x86/boot/cpucheck.c @@ -67,6 +67,13 @@ static int is_transmeta(void) cpu_vendor[2] == A32('M', 'x', '8', '6'); } +static int is_intel(void) +{ + return cpu_vendor[0] == A32('G', 'e', 'n', 'u') && + cpu_vendor[1] == A32('i', 'n', 'e', 'I') && + cpu_vendor[2] == A32('n', 't', 'e', 'l'); +} + /* Returns a bitmask of which words we have error bits in */ static int check_cpuflags(void) { @@ -153,6 +160,19 @@ int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr) asm("wrmsr" : : "a" (eax), "d" (edx), "c" (ecx)); err = check_cpuflags(); + } else if (err == 0x01 && + !(err_flags[0] & ~(1 << X86_FEATURE_PAE)) && + is_intel() && cpu.level == 6 && + (cpu.model == 9 || cpu.model == 13)) { + /* PAE is disabled on this Pentium M but can be forced */ + if (cmdline_find_option_bool("forcepae")) { + puts("WARNING: Forcing PAE in CPU flags\n"); + set_bit(X86_FEATURE_PAE, cpu.flags); + err = check_cpuflags(); + } + else { + puts("WARNING: PAE disabled. Use parameter 'forcepae' to enable at your own risk!\n"); + } } if (err_flags_ptr) diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index e099f9502ace..bc507d7640f8 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -217,9 +217,14 @@ #define X86_FEATURE_INVPCID (9*32+10) /* Invalidate Processor Context ID */ #define X86_FEATURE_RTM (9*32+11) /* Restricted Transactional Memory */ #define X86_FEATURE_MPX (9*32+14) /* Memory Protection Extension */ +#define X86_FEATURE_AVX512F (9*32+16) /* AVX-512 Foundation */ #define X86_FEATURE_RDSEED (9*32+18) /* The RDSEED instruction */ #define X86_FEATURE_ADX (9*32+19) /* The ADCX and ADOX instructions */ #define X86_FEATURE_SMAP (9*32+20) /* Supervisor Mode Access Prevention */ +#define X86_FEATURE_CLFLUSHOPT (9*32+23) /* CLFLUSHOPT instruction */ +#define X86_FEATURE_AVX512PF (9*32+26) /* AVX-512 Prefetch */ +#define X86_FEATURE_AVX512ER (9*32+27) /* AVX-512 Exponential and Reciprocal */ +#define X86_FEATURE_AVX512CD (9*32+28) /* AVX-512 Conflict Detection */ /* * BUG word(s) diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h index e139b13f2a33..de36f22eb0b9 100644 --- a/arch/x86/include/asm/msr.h +++ b/arch/x86/include/asm/msr.h @@ -214,6 +214,8 @@ do { \ struct msr *msrs_alloc(void); void msrs_free(struct msr *msrs); +int msr_set_bit(u32 msr, u8 bit); +int msr_clear_bit(u32 msr, u8 bit); #ifdef CONFIG_SMP int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h); diff --git a/arch/x86/include/asm/special_insns.h b/arch/x86/include/asm/special_insns.h index 645cad2c95ff..e820c080a4e9 100644 --- a/arch/x86/include/asm/special_insns.h +++ b/arch/x86/include/asm/special_insns.h @@ -191,6 +191,14 @@ static inline void clflush(volatile void *__p) asm volatile("clflush %0" : "+m" (*(volatile char __force *)__p)); } +static inline void clflushopt(volatile void *__p) +{ + alternative_io(".byte " __stringify(NOP_DS_PREFIX) "; clflush %P0", + ".byte 0x66; clflush %P0", + X86_FEATURE_CLFLUSHOPT, + "+m" (*(volatile char __force *)__p)); +} + #define nop() asm volatile ("nop") diff --git a/arch/x86/include/asm/xsave.h b/arch/x86/include/asm/xsave.h index 554738963b28..6c1d7411eb00 100644 --- a/arch/x86/include/asm/xsave.h +++ b/arch/x86/include/asm/xsave.h @@ -6,11 +6,14 @@ #define XSTATE_CPUID 0x0000000d -#define XSTATE_FP 0x1 -#define XSTATE_SSE 0x2 -#define XSTATE_YMM 0x4 -#define XSTATE_BNDREGS 0x8 -#define XSTATE_BNDCSR 0x10 +#define XSTATE_FP 0x1 +#define XSTATE_SSE 0x2 +#define XSTATE_YMM 0x4 +#define XSTATE_BNDREGS 0x8 +#define XSTATE_BNDCSR 0x10 +#define XSTATE_OPMASK 0x20 +#define XSTATE_ZMM_Hi256 0x40 +#define XSTATE_Hi16_ZMM 0x80 #define XSTATE_FPSSE (XSTATE_FP | XSTATE_SSE) @@ -23,7 +26,8 @@ #define XSAVE_YMM_OFFSET (XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET) /* Supported features which support lazy state saving */ -#define XSTATE_LAZY (XSTATE_FP | XSTATE_SSE | XSTATE_YMM) +#define XSTATE_LAZY (XSTATE_FP | XSTATE_SSE | XSTATE_YMM \ + | XSTATE_OPMASK | XSTATE_ZMM_Hi256 | XSTATE_Hi16_ZMM) /* Supported features which require eager state saving */ #define XSTATE_EAGER (XSTATE_BNDREGS | XSTATE_BNDCSR) diff --git a/arch/x86/include/uapi/asm/msr-index.h b/arch/x86/include/uapi/asm/msr-index.h index c19fc60ff062..4924f4be2b99 100644 --- a/arch/x86/include/uapi/asm/msr-index.h +++ b/arch/x86/include/uapi/asm/msr-index.h @@ -368,33 +368,58 @@ #define THERM_LOG_THRESHOLD1 (1 << 9) /* MISC_ENABLE bits: architectural */ -#define MSR_IA32_MISC_ENABLE_FAST_STRING (1ULL << 0) -#define MSR_IA32_MISC_ENABLE_TCC (1ULL << 1) -#define MSR_IA32_MISC_ENABLE_EMON (1ULL << 7) -#define MSR_IA32_MISC_ENABLE_BTS_UNAVAIL (1ULL << 11) -#define MSR_IA32_MISC_ENABLE_PEBS_UNAVAIL (1ULL << 12) -#define MSR_IA32_MISC_ENABLE_ENHANCED_SPEEDSTEP (1ULL << 16) -#define MSR_IA32_MISC_ENABLE_MWAIT (1ULL << 18) -#define MSR_IA32_MISC_ENABLE_LIMIT_CPUID (1ULL << 22) -#define MSR_IA32_MISC_ENABLE_XTPR_DISABLE (1ULL << 23) -#define MSR_IA32_MISC_ENABLE_XD_DISABLE (1ULL << 34) +#define MSR_IA32_MISC_ENABLE_FAST_STRING_BIT 0 +#define MSR_IA32_MISC_ENABLE_FAST_STRING (1ULL << MSR_IA32_MISC_ENABLE_FAST_STRING_BIT) +#define MSR_IA32_MISC_ENABLE_TCC_BIT 1 +#define MSR_IA32_MISC_ENABLE_TCC (1ULL << MSR_IA32_MISC_ENABLE_TCC_BIT) +#define MSR_IA32_MISC_ENABLE_EMON_BIT 7 +#define MSR_IA32_MISC_ENABLE_EMON (1ULL << MSR_IA32_MISC_ENABLE_EMON_BIT) +#define MSR_IA32_MISC_ENABLE_BTS_UNAVAIL_BIT 11 +#define MSR_IA32_MISC_ENABLE_BTS_UNAVAIL (1ULL << MSR_IA32_MISC_ENABLE_BTS_UNAVAIL_BIT) +#define MSR_IA32_MISC_ENABLE_PEBS_UNAVAIL_BIT 12 +#define MSR_IA32_MISC_ENABLE_PEBS_UNAVAIL (1ULL << MSR_IA32_MISC_ENABLE_PEBS_UNAVAIL_BIT) +#define MSR_IA32_MISC_ENABLE_ENHANCED_SPEEDSTEP_BIT 16 +#define MSR_IA32_MISC_ENABLE_ENHANCED_SPEEDSTEP (1ULL << MSR_IA32_MISC_ENABLE_ENHANCED_SPEEDSTEP_BIT) +#define MSR_IA32_MISC_ENABLE_MWAIT_BIT 18 +#define MSR_IA32_MISC_ENABLE_MWAIT (1ULL << MSR_IA32_MISC_ENABLE_MWAIT_BIT) +#define MSR_IA32_MISC_ENABLE_LIMIT_CPUID_BIT 22 +#define MSR_IA32_MISC_ENABLE_LIMIT_CPUID (1ULL << MSR_IA32_MISC_ENABLE_LIMIT_CPUID_BIT); +#define MSR_IA32_MISC_ENABLE_XTPR_DISABLE_BIT 23 +#define MSR_IA32_MISC_ENABLE_XTPR_DISABLE (1ULL << MSR_IA32_MISC_ENABLE_XTPR_DISABLE_BIT) +#define MSR_IA32_MISC_ENABLE_XD_DISABLE_BIT 34 +#define MSR_IA32_MISC_ENABLE_XD_DISABLE (1ULL << MSR_IA32_MISC_ENABLE_XD_DISABLE_BIT) /* MISC_ENABLE bits: model-specific, meaning may vary from core to core */ -#define MSR_IA32_MISC_ENABLE_X87_COMPAT (1ULL << 2) -#define MSR_IA32_MISC_ENABLE_TM1 (1ULL << 3) -#define MSR_IA32_MISC_ENABLE_SPLIT_LOCK_DISABLE (1ULL << 4) -#define MSR_IA32_MISC_ENABLE_L3CACHE_DISABLE (1ULL << 6) -#define MSR_IA32_MISC_ENABLE_SUPPRESS_LOCK (1ULL << 8) -#define MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE (1ULL << 9) -#define MSR_IA32_MISC_ENABLE_FERR (1ULL << 10) -#define MSR_IA32_MISC_ENABLE_FERR_MULTIPLEX (1ULL << 10) -#define MSR_IA32_MISC_ENABLE_TM2 (1ULL << 13) -#define MSR_IA32_MISC_ENABLE_ADJ_PREF_DISABLE (1ULL << 19) -#define MSR_IA32_MISC_ENABLE_SPEEDSTEP_LOCK (1ULL << 20) -#define MSR_IA32_MISC_ENABLE_L1D_CONTEXT (1ULL << 24) -#define MSR_IA32_MISC_ENABLE_DCU_PREF_DISABLE (1ULL << 37) -#define MSR_IA32_MISC_ENABLE_TURBO_DISABLE (1ULL << 38) -#define MSR_IA32_MISC_ENABLE_IP_PREF_DISABLE (1ULL << 39) +#define MSR_IA32_MISC_ENABLE_X87_COMPAT_BIT 2 +#define MSR_IA32_MISC_ENABLE_X87_COMPAT (1ULL << MSR_IA32_MISC_ENABLE_X87_COMPAT_BIT) +#define MSR_IA32_MISC_ENABLE_TM1_BIT 3 +#define MSR_IA32_MISC_ENABLE_TM1 (1ULL << MSR_IA32_MISC_ENABLE_TM1_BIT) +#define MSR_IA32_MISC_ENABLE_SPLIT_LOCK_DISABLE_BIT 4 +#define MSR_IA32_MISC_ENABLE_SPLIT_LOCK_DISABLE (1ULL << MSR_IA32_MISC_ENABLE_SPLIT_LOCK_DISABLE_BIT) +#define MSR_IA32_MISC_ENABLE_L3CACHE_DISABLE_BIT 6 +#define MSR_IA32_MISC_ENABLE_L3CACHE_DISABLE (1ULL << MSR_IA32_MISC_ENABLE_L3CACHE_DISABLE_BIT) +#define MSR_IA32_MISC_ENABLE_SUPPRESS_LOCK_BIT 8 +#define MSR_IA32_MISC_ENABLE_SUPPRESS_LOCK (1ULL << MSR_IA32_MISC_ENABLE_SUPPRESS_LOCK_BIT) +#define MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE_BIT 9 +#define MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE (1ULL << MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE_BIT) +#define MSR_IA32_MISC_ENABLE_FERR_BIT 10 +#define MSR_IA32_MISC_ENABLE_FERR (1ULL << MSR_IA32_MISC_ENABLE_FERR_BIT) +#define MSR_IA32_MISC_ENABLE_FERR_MULTIPLEX_BIT 10 +#define MSR_IA32_MISC_ENABLE_FERR_MULTIPLEX (1ULL << MSR_IA32_MISC_ENABLE_FERR_MULTIPLEX_BIT) +#define MSR_IA32_MISC_ENABLE_TM2_BIT 13 +#define MSR_IA32_MISC_ENABLE_TM2 (1ULL << MSR_IA32_MISC_ENABLE_TM2_BIT) +#define MSR_IA32_MISC_ENABLE_ADJ_PREF_DISABLE_BIT 19 +#define MSR_IA32_MISC_ENABLE_ADJ_PREF_DISABLE (1ULL << MSR_IA32_MISC_ENABLE_ADJ_PREF_DISABLE_BIT) +#define MSR_IA32_MISC_ENABLE_SPEEDSTEP_LOCK_BIT 20 +#define MSR_IA32_MISC_ENABLE_SPEEDSTEP_LOCK (1ULL << MSR_IA32_MISC_ENABLE_SPEEDSTEP_LOCK_BIT) +#define MSR_IA32_MISC_ENABLE_L1D_CONTEXT_BIT 24 +#define MSR_IA32_MISC_ENABLE_L1D_CONTEXT (1ULL << MSR_IA32_MISC_ENABLE_L1D_CONTEXT_BIT) +#define MSR_IA32_MISC_ENABLE_DCU_PREF_DISABLE_BIT 37 +#define MSR_IA32_MISC_ENABLE_DCU_PREF_DISABLE (1ULL << MSR_IA32_MISC_ENABLE_DCU_PREF_DISABLE_BIT) +#define MSR_IA32_MISC_ENABLE_TURBO_DISABLE_BIT 38 +#define MSR_IA32_MISC_ENABLE_TURBO_DISABLE (1ULL << MSR_IA32_MISC_ENABLE_TURBO_DISABLE_BIT) +#define MSR_IA32_MISC_ENABLE_IP_PREF_DISABLE_BIT 39 +#define MSR_IA32_MISC_ENABLE_IP_PREF_DISABLE (1ULL << MSR_IA32_MISC_ENABLE_IP_PREF_DISABLE_BIT) #define MSR_IA32_TSC_DEADLINE 0x000006E0 diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index c67ffa686064..ce8b8ff0e0ef 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -218,7 +218,7 @@ static void amd_k7_smp_check(struct cpuinfo_x86 *c) */ WARN_ONCE(1, "WARNING: This combination of AMD" " processors is not suitable for SMP.\n"); - add_taint(TAINT_UNSAFE_SMP, LOCKDEP_NOW_UNRELIABLE); + add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE); } static void init_amd_k7(struct cpuinfo_x86 *c) @@ -233,9 +233,7 @@ static void init_amd_k7(struct cpuinfo_x86 *c) if (c->x86_model >= 6 && c->x86_model <= 10) { if (!cpu_has(c, X86_FEATURE_XMM)) { printk(KERN_INFO "Enabling disabled K7/SSE Support.\n"); - rdmsr(MSR_K7_HWCR, l, h); - l &= ~0x00008000; - wrmsr(MSR_K7_HWCR, l, h); + msr_clear_bit(MSR_K7_HWCR, 15); set_cpu_cap(c, X86_FEATURE_XMM); } } @@ -509,14 +507,8 @@ static void early_init_amd(struct cpuinfo_x86 *c) #endif /* F16h erratum 793, CVE-2013-6885 */ - if (c->x86 == 0x16 && c->x86_model <= 0xf) { - u64 val; - - rdmsrl(MSR_AMD64_LS_CFG, val); - if (!(val & BIT(15))) - wrmsrl(MSR_AMD64_LS_CFG, val | BIT(15)); - } - + if (c->x86 == 0x16 && c->x86_model <= 0xf) + msr_set_bit(MSR_AMD64_LS_CFG, 15); } static const int amd_erratum_383[]; @@ -536,11 +528,8 @@ static void init_amd(struct cpuinfo_x86 *c) * Errata 63 for SH-B3 steppings * Errata 122 for all steppings (F+ have it disabled by default) */ - if (c->x86 == 0xf) { - rdmsrl(MSR_K7_HWCR, value); - value |= 1 << 6; - wrmsrl(MSR_K7_HWCR, value); - } + if (c->x86 == 0xf) + msr_set_bit(MSR_K7_HWCR, 6); #endif early_init_amd(c); @@ -623,14 +612,11 @@ static void init_amd(struct cpuinfo_x86 *c) (c->x86_model >= 0x10) && (c->x86_model <= 0x1f) && !cpu_has(c, X86_FEATURE_TOPOEXT)) { - if (!rdmsrl_safe(0xc0011005, &value)) { - value |= 1ULL << 54; - wrmsrl_safe(0xc0011005, value); + if (msr_set_bit(0xc0011005, 54) > 0) { rdmsrl(0xc0011005, value); - if (value & (1ULL << 54)) { + if (value & BIT_64(54)) { set_cpu_cap(c, X86_FEATURE_TOPOEXT); - printk(KERN_INFO FW_INFO "CPU: Re-enabling " - "disabled Topology Extensions Support\n"); + pr_info(FW_INFO "CPU: Re-enabling disabled Topology Extensions Support.\n"); } } } @@ -709,19 +695,12 @@ static void init_amd(struct cpuinfo_x86 *c) * Disable GART TLB Walk Errors on Fam10h. We do this here * because this is always needed when GART is enabled, even in a * kernel which has no MCE support built in. - * BIOS should disable GartTlbWlk Errors themself. If - * it doesn't do it here as suggested by the BKDG. + * BIOS should disable GartTlbWlk Errors already. If + * it doesn't, do it here as suggested by the BKDG. * * Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012 */ - u64 mask; - int err; - - err = rdmsrl_safe(MSR_AMD64_MCx_MASK(4), &mask); - if (err == 0) { - mask |= (1 << 10); - wrmsrl_safe(MSR_AMD64_MCx_MASK(4), mask); - } + msr_set_bit(MSR_AMD64_MCx_MASK(4), 10); /* * On family 10h BIOS may not have properly enabled WC+ support, @@ -733,10 +712,7 @@ static void init_amd(struct cpuinfo_x86 *c) * NOTE: we want to use the _safe accessors so as not to #GP kvm * guests on older kvm hosts. */ - - rdmsrl_safe(MSR_AMD64_BU_CFG2, &value); - value &= ~(1ULL << 24); - wrmsrl_safe(MSR_AMD64_BU_CFG2, value); + msr_clear_bit(MSR_AMD64_BU_CFG2, 24); if (cpu_has_amd_erratum(c, amd_erratum_383)) set_cpu_bug(c, X86_BUG_AMD_TLB_MMATCH); diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 5cd9bfabd645..897d6201ef10 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -31,11 +31,8 @@ static void early_init_intel(struct cpuinfo_x86 *c) /* Unmask CPUID levels if masked: */ if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) { - rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable); - - if (misc_enable & MSR_IA32_MISC_ENABLE_LIMIT_CPUID) { - misc_enable &= ~MSR_IA32_MISC_ENABLE_LIMIT_CPUID; - wrmsrl(MSR_IA32_MISC_ENABLE, misc_enable); + if (msr_clear_bit(MSR_IA32_MISC_ENABLE, + MSR_IA32_MISC_ENABLE_LIMIT_CPUID_BIT) > 0) { c->cpuid_level = cpuid_eax(0); get_cpu_cap(c); } @@ -129,16 +126,10 @@ static void early_init_intel(struct cpuinfo_x86 *c) * Ingo Molnar reported a Pentium D (model 6) and a Xeon * (model 2) with the same problem. */ - if (c->x86 == 15) { - rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable); - - if (misc_enable & MSR_IA32_MISC_ENABLE_FAST_STRING) { - printk(KERN_INFO "kmemcheck: Disabling fast string operations\n"); - - misc_enable &= ~MSR_IA32_MISC_ENABLE_FAST_STRING; - wrmsrl(MSR_IA32_MISC_ENABLE, misc_enable); - } - } + if (c->x86 == 15) + if (msr_clear_bit(MSR_IA32_MISC_ENABLE, + MSR_IA32_MISC_ENABLE_FAST_STRING_BIT) > 0) + pr_info("kmemcheck: Disabling fast string operations\n"); #endif /* @@ -195,10 +186,16 @@ static void intel_smp_check(struct cpuinfo_x86 *c) } } +static int forcepae; +static int __init forcepae_setup(char *__unused) +{ + forcepae = 1; + return 1; +} +__setup("forcepae", forcepae_setup); + static void intel_workarounds(struct cpuinfo_x86 *c) { - unsigned long lo, hi; - #ifdef CONFIG_X86_F00F_BUG /* * All current models of Pentium and Pentium with MMX technology CPUs @@ -224,17 +221,27 @@ static void intel_workarounds(struct cpuinfo_x86 *c) if ((c->x86<<8 | c->x86_model<<4 | c->x86_mask) < 0x633) clear_cpu_cap(c, X86_FEATURE_SEP); + /* + * PAE CPUID issue: many Pentium M report no PAE but may have a + * functionally usable PAE implementation. + * Forcefully enable PAE if kernel parameter "forcepae" is present. + */ + if (forcepae) { + printk(KERN_WARNING "PAE forced!\n"); + set_cpu_cap(c, X86_FEATURE_PAE); + add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE); + } + /* * P4 Xeon errata 037 workaround. * Hardware prefetcher may cause stale data to be loaded into the cache. */ if ((c->x86 == 15) && (c->x86_model == 1) && (c->x86_mask == 1)) { - rdmsr(MSR_IA32_MISC_ENABLE, lo, hi); - if ((lo & MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE) == 0) { - printk (KERN_INFO "CPU: C0 stepping P4 Xeon detected.\n"); - printk (KERN_INFO "CPU: Disabling hardware prefetching (Errata 037)\n"); - lo |= MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE; - wrmsr(MSR_IA32_MISC_ENABLE, lo, hi); + if (msr_set_bit(MSR_IA32_MISC_ENABLE, + MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE_BIT) + > 0) { + pr_info("CPU: C0 stepping P4 Xeon detected.\n"); + pr_info("CPU: Disabling hardware prefetching (Errata 037)\n"); } } diff --git a/arch/x86/lib/msr.c b/arch/x86/lib/msr.c index 8f8eebdca7d4..db9db446b71a 100644 --- a/arch/x86/lib/msr.c +++ b/arch/x86/lib/msr.c @@ -8,7 +8,7 @@ struct msr *msrs_alloc(void) msrs = alloc_percpu(struct msr); if (!msrs) { - pr_warning("%s: error allocating msrs\n", __func__); + pr_warn("%s: error allocating msrs\n", __func__); return NULL; } @@ -21,3 +21,90 @@ void msrs_free(struct msr *msrs) free_percpu(msrs); } EXPORT_SYMBOL(msrs_free); + +/** + * Read an MSR with error handling + * + * @msr: MSR to read + * @m: value to read into + * + * It returns read data only on success, otherwise it doesn't change the output + * argument @m. + * + */ +int msr_read(u32 msr, struct msr *m) +{ + int err; + u64 val; + + err = rdmsrl_safe(msr, &val); + if (!err) + m->q = val; + + return err; +} + +/** + * Write an MSR with error handling + * + * @msr: MSR to write + * @m: value to write + */ +int msr_write(u32 msr, struct msr *m) +{ + return wrmsrl_safe(msr, m->q); +} + +static inline int __flip_bit(u32 msr, u8 bit, bool set) +{ + struct msr m, m1; + int err = -EINVAL; + + if (bit > 63) + return err; + + err = msr_read(msr, &m); + if (err) + return err; + + m1 = m; + if (set) + m1.q |= BIT_64(bit); + else + m1.q &= ~BIT_64(bit); + + if (m1.q == m.q) + return 0; + + err = msr_write(msr, &m); + if (err) + return err; + + return 1; +} + +/** + * Set @bit in a MSR @msr. + * + * Retval: + * < 0: An error was encountered. + * = 0: Bit was already set. + * > 0: Hardware accepted the MSR write. + */ +int msr_set_bit(u32 msr, u8 bit) +{ + return __flip_bit(msr, bit, true); +} + +/** + * Clear @bit in a MSR @msr. + * + * Retval: + * < 0: An error was encountered. + * = 0: Bit was already cleared. + * > 0: Hardware accepted the MSR write. + */ +int msr_clear_bit(u32 msr, u8 bit) +{ + return __flip_bit(msr, bit, false); +} diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index ba957c9b677c..cf125b301b69 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -126,8 +126,8 @@ within(unsigned long addr, unsigned long start, unsigned long end) * @vaddr: virtual start address * @size: number of bytes to flush * - * clflush is an unordered instruction which needs fencing with mfence - * to avoid ordering issues. + * clflushopt is an unordered instruction which needs fencing with mfence or + * sfence to avoid ordering issues. */ void clflush_cache_range(void *vaddr, unsigned int size) { @@ -136,11 +136,11 @@ void clflush_cache_range(void *vaddr, unsigned int size) mb(); for (; vaddr < vend; vaddr += boot_cpu_data.x86_clflush_size) - clflush(vaddr); + clflushopt(vaddr); /* * Flush any possible final partial cacheline: */ - clflush(vend); + clflushopt(vend); mb(); } diff --git a/drivers/gpu/drm/drm_cache.c b/drivers/gpu/drm/drm_cache.c index bb8f58012189..534cb89b160d 100644 --- a/drivers/gpu/drm/drm_cache.c +++ b/drivers/gpu/drm/drm_cache.c @@ -32,6 +32,12 @@ #include #if defined(CONFIG_X86) + +/* + * clflushopt is an unordered instruction which needs fencing with mfence or + * sfence to avoid ordering issues. For drm_clflush_page this fencing happens + * in the caller. + */ static void drm_clflush_page(struct page *page) { @@ -44,7 +50,7 @@ drm_clflush_page(struct page *page) page_virtual = kmap_atomic(page); for (i = 0; i < PAGE_SIZE; i += size) - clflush(page_virtual + i); + clflushopt(page_virtual + i); kunmap_atomic(page_virtual); } @@ -133,7 +139,7 @@ drm_clflush_virt_range(char *addr, unsigned long length) mb(); for (; addr < end; addr += boot_cpu_data.x86_clflush_size) clflush(addr); - clflush(end - 1); + clflushopt(end - 1); mb(); return; } diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 196d1ea86df0..08fb02477641 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -458,7 +458,7 @@ extern enum system_states { #define TAINT_PROPRIETARY_MODULE 0 #define TAINT_FORCED_MODULE 1 -#define TAINT_UNSAFE_SMP 2 +#define TAINT_CPU_OUT_OF_SPEC 2 #define TAINT_FORCED_RMMOD 3 #define TAINT_MACHINE_CHECK 4 #define TAINT_BAD_PAGE 5 diff --git a/kernel/module.c b/kernel/module.c index d24fcf29cb64..ca2c1aded7ee 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1015,7 +1015,7 @@ static size_t module_flags_taint(struct module *mod, char *buf) buf[l++] = 'C'; /* * TAINT_FORCED_RMMOD: could be added. - * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't + * TAINT_CPU_OUT_OF_SPEC, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't * apply to modules. */ return l; diff --git a/kernel/panic.c b/kernel/panic.c index 6d6300375090..2270cfd1d6be 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -199,7 +199,7 @@ struct tnt { static const struct tnt tnts[] = { { TAINT_PROPRIETARY_MODULE, 'P', 'G' }, { TAINT_FORCED_MODULE, 'F', ' ' }, - { TAINT_UNSAFE_SMP, 'S', ' ' }, + { TAINT_CPU_OUT_OF_SPEC, 'S', ' ' }, { TAINT_FORCED_RMMOD, 'R', ' ' }, { TAINT_MACHINE_CHECK, 'M', ' ' }, { TAINT_BAD_PAGE, 'B', ' ' },