From 8e5780fdeef7dc490b3f0b3a62704593721fa4f3 Mon Sep 17 00:00:00 2001 From: Fenghua Yu Date: Thu, 20 Feb 2014 13:24:50 -0800 Subject: x86, AVX-512: AVX-512 Feature Detection AVX-512 is an extention of AVX2. Its spec can be found at: http://download-software.intel.com/sites/default/files/managed/71/2e/319433-017.pdf This patch detects AVX-512 features by CPUID. Signed-off-by: Fenghua Yu Link: http://lkml.kernel.org/r/1392931491-33237-1-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin Cc: # hw enabling diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index e099f95..5f12968 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -217,9 +217,13 @@ #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_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) -- cgit v0.10.2 From c2bc11f10a39527cd1bb252097b5525664560956 Mon Sep 17 00:00:00 2001 From: Fenghua Yu Date: Thu, 20 Feb 2014 13:24:51 -0800 Subject: x86, AVX-512: Enable AVX-512 States Context Switch This patch enables Opmask, ZMM_Hi256, and Hi16_ZMM AVX-512 states for xstate context switch. Signed-off-by: Fenghua Yu Link: http://lkml.kernel.org/r/1392931491-33237-2-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin Cc: # hw enabling diff --git a/arch/x86/include/asm/xsave.h b/arch/x86/include/asm/xsave.h index 5547389..6c1d741 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) -- cgit v0.10.2 From 171699f7630c92d0a928f83e5fb3aeabe35398c0 Mon Sep 17 00:00:00 2001 From: Ross Zwisler Date: Wed, 26 Feb 2014 12:06:49 -0700 Subject: x86: Add support for the clflushopt instruction Add support for the new clflushopt instruction. This instruction was announced in the document "Intel Architecture Instruction Set Extensions Programming Reference" with Ref # 319433-018. http://download-software.intel.com/sites/default/files/managed/50/1a/319433-018.pdf [ hpa: changed the feature flag to simply X86_FEATURE_CLFLUSHOPT - if that is what we want to report in /proc/cpuinfo anyway... ] Signed-off-by: Ross Zwisler Link: http://lkml.kernel.org/r/1393441612-19729-2-git-send-email-ross.zwisler@linux.intel.com Signed-off-by: H. Peter Anvin diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index 5f12968..bc507d7 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -221,6 +221,7 @@ #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 */ diff --git a/arch/x86/include/asm/special_insns.h b/arch/x86/include/asm/special_insns.h index 645cad2..e820c08 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") -- cgit v0.10.2 From 8b80fd8b45458a7d0b726d454c51c5219e0fb2ee Mon Sep 17 00:00:00 2001 From: Ross Zwisler Date: Wed, 26 Feb 2014 12:06:50 -0700 Subject: x86: Use clflushopt in clflush_cache_range If clflushopt is available on the system, use it instead of clflush in clflush_cache_range. Signed-off-by: Ross Zwisler Link: http://lkml.kernel.org/r/1393441612-19729-3-git-send-email-ross.zwisler@linux.intel.com Signed-off-by: H. Peter Anvin diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index b3b19f4..b1c4672 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(); } -- cgit v0.10.2 From 2a0c772f1967565d5b71a98012e74d5a7bddc1c4 Mon Sep 17 00:00:00 2001 From: Ross Zwisler Date: Wed, 26 Feb 2014 12:06:51 -0700 Subject: x86: Use clflushopt in drm_clflush_page If clflushopt is available on the system, use it instead of clflush in drm_clflush_page. Signed-off-by: Ross Zwisler Link: http://lkml.kernel.org/r/1393441612-19729-4-git-send-email-ross.zwisler@linux.intel.com Signed-off-by: H. Peter Anvin diff --git a/drivers/gpu/drm/drm_cache.c b/drivers/gpu/drm/drm_cache.c index bb8f580..c518fb6 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); } -- cgit v0.10.2 From 2a0788dc9bc46789ec98aea0f30c6fb420196b12 Mon Sep 17 00:00:00 2001 From: Ross Zwisler Date: Wed, 26 Feb 2014 12:06:52 -0700 Subject: x86: Use clflushopt in drm_clflush_virt_range If clflushopt is available on the system, use it instead of clflush in drm_clflush_virt_range. Signed-off-by: Ross Zwisler Link: http://lkml.kernel.org/r/1393441612-19729-5-git-send-email-ross.zwisler@linux.intel.com Signed-off-by: H. Peter Anvin diff --git a/drivers/gpu/drm/drm_cache.c b/drivers/gpu/drm/drm_cache.c index c518fb6..534cb89 100644 --- a/drivers/gpu/drm/drm_cache.c +++ b/drivers/gpu/drm/drm_cache.c @@ -139,7 +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; } -- cgit v0.10.2 From 22085a66c2fab6cf9b9393c056a3600a6b4735de Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Sun, 9 Mar 2014 18:05:23 +0100 Subject: x86: Add another set of MSR accessor functions We very often need to set or clear a bit in an MSR as a result of doing some sort of a hardware configuration. Add generic versions of that repeated functionality in order to save us a bunch of duplicated code in the early CPU vendor detection/config code. Signed-off-by: Borislav Petkov Link: http://lkml.kernel.org/r/1394384725-10796-2-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h index e139b13..de36f22 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/lib/msr.c b/arch/x86/lib/msr.c index 8f8eebd..db9db44 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); +} -- cgit v0.10.2 From 8f86a7373a1c8ee52d3cc64adf7f2ace13fd24ed Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Sun, 9 Mar 2014 18:05:24 +0100 Subject: x86, AMD: Convert to the new bit access MSR accessors ... and save us a bunch of code. Signed-off-by: Borislav Petkov Link: http://lkml.kernel.org/r/1394384725-10796-3-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index c67ffa6..b85e43a 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.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); -- cgit v0.10.2 From c0a639ad0bc6b178b46996bd1f821a04643e2bde Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Sun, 9 Mar 2014 18:05:25 +0100 Subject: x86, Intel: Convert to the new bit access MSR accessors ... and save some lines of code. Signed-off-by: Borislav Petkov Link: http://lkml.kernel.org/r/1394384725-10796-4-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin diff --git a/arch/x86/include/uapi/asm/msr-index.h b/arch/x86/include/uapi/asm/msr-index.h index c19fc60..045e6db 100644 --- a/arch/x86/include/uapi/asm/msr-index.h +++ b/arch/x86/include/uapi/asm/msr-index.h @@ -368,14 +368,16 @@ #define THERM_LOG_THRESHOLD1 (1 << 9) /* MISC_ENABLE bits: architectural */ -#define MSR_IA32_MISC_ENABLE_FAST_STRING (1ULL << 0) +#define MSR_BIT_FAST_STRING 0 +#define MSR_IA32_MISC_ENABLE_FAST_STRING (1ULL << MSR_BIT_FAST_STRING) #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_BIT_LIMIT_CPUID 22 +#define MSR_IA32_MISC_ENABLE_LIMIT_CPUID (1ULL << MSR_BIT_LIMIT_CPUID); #define MSR_IA32_MISC_ENABLE_XTPR_DISABLE (1ULL << 23) #define MSR_IA32_MISC_ENABLE_XD_DISABLE (1ULL << 34) @@ -385,7 +387,8 @@ #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_BIT_PRF_DIS 9 +#define MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE (1ULL << MSR_BIT_PRF_DIS) #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) diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 5cd9bfa..44ca631 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -31,11 +31,7 @@ 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_BIT_LIMIT_CPUID) > 0) { c->cpuid_level = cpuid_eax(0); get_cpu_cap(c); } @@ -129,16 +125,9 @@ 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_BIT_FAST_STRING) > 0) + pr_info("kmemcheck: Disabling fast string operations\n"); #endif /* @@ -197,8 +186,6 @@ static void intel_smp_check(struct cpuinfo_x86 *c) 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 @@ -229,12 +216,9 @@ static void intel_workarounds(struct cpuinfo_x86 *c) * 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_BIT_PRF_DIS) > 0) { + pr_info("CPU: C0 stepping P4 Xeon detected.\n"); + pr_info("CPU: Disabling hardware prefetching (Errata 037)\n"); } } -- cgit v0.10.2 From 0b131be8d4125b32eb5b94e84f4f9dee6a0ef797 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Thu, 13 Mar 2014 15:40:52 -0700 Subject: x86, intel: Make MSR_IA32_MISC_ENABLE bit constants systematic Replace somewhat arbitrary constants for bits in MSR_IA32_MISC_ENABLE with verbose but systematic ones. Add _BIT defines for all the rest of them, too. Signed-off-by: H. Peter Anvin diff --git a/arch/x86/include/uapi/asm/msr-index.h b/arch/x86/include/uapi/asm/msr-index.h index 045e6db..4924f4b 100644 --- a/arch/x86/include/uapi/asm/msr-index.h +++ b/arch/x86/include/uapi/asm/msr-index.h @@ -368,36 +368,58 @@ #define THERM_LOG_THRESHOLD1 (1 << 9) /* MISC_ENABLE bits: architectural */ -#define MSR_BIT_FAST_STRING 0 -#define MSR_IA32_MISC_ENABLE_FAST_STRING (1ULL << MSR_BIT_FAST_STRING) -#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_BIT_LIMIT_CPUID 22 -#define MSR_IA32_MISC_ENABLE_LIMIT_CPUID (1ULL << MSR_BIT_LIMIT_CPUID); -#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_BIT_PRF_DIS 9 -#define MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE (1ULL << MSR_BIT_PRF_DIS) -#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/intel.c b/arch/x86/kernel/cpu/intel.c index 44ca631..34bbb55 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -31,7 +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)) { - if (msr_clear_bit(MSR_IA32_MISC_ENABLE, MSR_BIT_LIMIT_CPUID) > 0) { + 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); } @@ -126,7 +127,8 @@ static void early_init_intel(struct cpuinfo_x86 *c) * (model 2) with the same problem. */ if (c->x86 == 15) - if (msr_clear_bit(MSR_IA32_MISC_ENABLE, MSR_BIT_FAST_STRING) > 0) + 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 @@ -216,7 +218,9 @@ static void intel_workarounds(struct cpuinfo_x86 *c) * Hardware prefetcher may cause stale data to be loaded into the cache. */ if ((c->x86 == 15) && (c->x86_model == 1) && (c->x86_mask == 1)) { - if (msr_set_bit(MSR_IA32_MISC_ENABLE, MSR_BIT_PRF_DIS) > 0) { + 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"); } -- cgit v0.10.2 From 8c90487cdc64847b4fdd812ab3047f426fec4d13 Mon Sep 17 00:00:00 2001 From: Dave Jones Date: Wed, 26 Feb 2014 10:49:49 -0500 Subject: Rename TAINT_UNSAFE_SMP to TAINT_CPU_OUT_OF_SPEC Rename TAINT_UNSAFE_SMP to TAINT_CPU_OUT_OF_SPEC, so we can repurpose the flag to encompass a wider range of pushing the CPU beyond its warrany. Signed-off-by: Dave Jones Link: http://lkml.kernel.org/r/20140226154949.GA770@redhat.com Signed-off-by: H. Peter Anvin diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index b85e43a..ce8b8ff 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) diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 196d1ea..08fb024 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 d24fcf2..ca2c1ad 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 6d63003..2270cfd 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', ' ' }, -- cgit v0.10.2 From 69f2366c9456d0ce784cf5aba87ee77eeadc1d5e Mon Sep 17 00:00:00 2001 From: Chris Bainbridge Date: Fri, 7 Mar 2014 18:40:42 +0700 Subject: x86, cpu: Add forcepae parameter for booting PAE kernels on PAE-disabled Pentium M Many Pentium M systems disable PAE but may have a functionally usable PAE implementation. This adds the "forcepae" parameter which bypasses the boot check for PAE, and sets the CPU as being PAE capable. Using this parameter will taint the kernel with TAINT_CPU_OUT_OF_SPEC. Signed-off-by: Chris Bainbridge Link: http://lkml.kernel.org/r/20140307114040.GA4997@localhost Acked-by: Borislav Petkov Signed-off-by: H. Peter Anvin diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 7116fda..06600cc 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 100a9a1..f0d0b20 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/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 34bbb55..897d620 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -186,6 +186,14 @@ 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) { #ifdef CONFIG_X86_F00F_BUG @@ -214,6 +222,17 @@ static void intel_workarounds(struct cpuinfo_x86 *c) 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. */ -- cgit v0.10.2