From 066941bd4eeb159307a5d7d795100d0887c00442 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Wed, 21 Jan 2009 15:04:32 -0800 Subject: x86: unmask CPUID levels on Intel CPUs Impact: Fixes crashes with misconfigured BIOSes on XSAVE hardware Avuton Olrich reported early boot crashes with v2.6.28 and bisected it down to dc1e35c6e95e8923cf1d3510438b63c600fee1e2 ("x86, xsave: enable xsave/xrstor on cpus with xsave support"). If the CPUID limit bit in MSR_IA32_MISC_ENABLE is set, clear it to make all CPUID information available. This is required for some features to work, in particular XSAVE. Reported-and-bisected-by: Avuton Olrich Tested-by: Avuton Olrich Signed-off-by: H. Peter Anvin --- arch/x86/kernel/cpu/intel.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'arch/x86/kernel/cpu/intel.c') diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 8ea6929e974c..43c1dcf0bec7 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -29,6 +29,16 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c) { + u64 misc_enable; + + /* Unmask CPUID levels if masked */ + if (!rdmsrl_safe(MSR_IA32_MISC_ENABLE, &misc_enable) && + (misc_enable & MSR_IA32_MISC_ENABLE_LIMIT_CPUID)) { + misc_enable &= ~MSR_IA32_MISC_ENABLE_LIMIT_CPUID; + wrmsrl(MSR_IA32_MISC_ENABLE, misc_enable); + c->cpuid_level = cpuid_eax(0); + } + if ((c->x86 == 0xf && c->x86_model >= 0x03) || (c->x86 == 0x6 && c->x86_model >= 0x0e)) set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC); -- cgit v1.2.3 From 75a048119e76540d73132cfc8e0fa0c0a8bb6c83 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Thu, 22 Jan 2009 16:17:05 -0800 Subject: x86: handle PAT more like other CPU features Impact: Cleanup When PAT was originally introduced, it was handled specially for a few reasons: - PAT bugs are hard to track down, so we wanted to maintain a whitelist of CPUs. - The i386 and x86-64 CPUID code was not yet unified. Both of these are now obsolete, so handle PAT like any other features, including ordinary feature blacklisting due to known bugs. Signed-off-by: H. Peter Anvin --- arch/x86/kernel/cpu/intel.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'arch/x86/kernel/cpu/intel.c') diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 8ea6929e974c..20ce03acf04b 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -50,6 +50,18 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c) set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC); } + /* + * There is a known erratum on Pentium III and Core Solo + * and Core Duo CPUs. + * " Page with PAT set to WC while associated MTRR is UC + * may consolidate to UC " + * Because of this erratum, it is better to stick with + * setting WC in MTRR rather than using PAT on these CPUs. + * + * Enable PAT WC only on P4, Core 2 or later CPUs. + */ + if (c->x86 == 6 && c->x86_model < 15) + clear_cpu_cap(c, X86_FEATURE_PAT); } #ifdef CONFIG_X86_32 -- cgit v1.2.3 From 99fb4d349db7e7dacb2099c5cc320a9e2d31c1ef Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Mon, 26 Jan 2009 04:30:41 +0100 Subject: x86: unmask CPUID levels on Intel CPUs, fix Impact: fix boot hang on pre-model-15 Intel CPUs rdmsrl_safe() does not work in very early bootup code yet, because we dont have the pagefault handler installed yet so exception section does not get parsed. rdmsr_safe() will just crash and hang the bootup. So limit the MSR_IA32_MISC_ENABLE MSR read to those CPU types that support it. Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/intel.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) (limited to 'arch/x86/kernel/cpu/intel.c') diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 43c1dcf0bec7..549f2ada55f5 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -29,14 +29,17 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c) { - u64 misc_enable; - - /* Unmask CPUID levels if masked */ - if (!rdmsrl_safe(MSR_IA32_MISC_ENABLE, &misc_enable) && - (misc_enable & MSR_IA32_MISC_ENABLE_LIMIT_CPUID)) { - misc_enable &= ~MSR_IA32_MISC_ENABLE_LIMIT_CPUID; - wrmsrl(MSR_IA32_MISC_ENABLE, misc_enable); - c->cpuid_level = cpuid_eax(0); + /* Unmask CPUID levels if masked: */ + if (c->x86 == 6 && c->x86_model >= 15) { + u64 misc_enable; + + 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); + c->cpuid_level = cpuid_eax(0); + } } if ((c->x86 == 0xf && c->x86_model >= 0x03) || -- cgit v1.2.3 From 30a0fb947a68ad3ab8a7184e3b3d79dce10e3688 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Mon, 26 Jan 2009 09:40:58 -0800 Subject: x86: correct the CPUID pattern for MSR_IA32_MISC_ENABLE availability Impact: re-enable CPUID unmasking on affected processors As far as I am capable of discerning from the documentation, MSR_IA32_MISC_ENABLE should be available for all family 0xf CPUs, as well as family 6 for model >= 0xd (newer Pentium M). The documentation on this isn't ideal, so we need to be on the lookout for errors, still. Signed-off-by: H. Peter Anvin --- arch/x86/kernel/cpu/intel.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/kernel/cpu/intel.c') diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 549f2ada55f5..430e5c38a544 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -30,7 +30,7 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c) { /* Unmask CPUID levels if masked: */ - if (c->x86 == 6 && c->x86_model >= 15) { + if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) { u64 misc_enable; rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable); -- cgit v1.2.3 From 1dcdd3d15ecea0c22a09d4d001a39d425fceff2c Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Wed, 28 Jan 2009 17:55:37 +0100 Subject: x86: remove mach_apic.h Spread mach_apic.h definitions into genapic.h. (with some knock-on effects on smp.h and apic.h.) Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/intel.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/kernel/cpu/intel.c') diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 5deefae9064d..1cef0aa5e5dc 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -24,7 +24,7 @@ #ifdef CONFIG_X86_LOCAL_APIC #include #include -#include +#include #endif static void __cpuinit early_init_intel(struct cpuinfo_x86 *c) -- cgit v1.2.3 From e736ad548db152776de61d7a26805cfae77ce5ce Mon Sep 17 00:00:00 2001 From: "Pallipadi, Venkatesh" Date: Fri, 6 Feb 2009 16:52:05 -0800 Subject: x86: add clflush before monitor for Intel 7400 series For Intel 7400 series CPUs, the recommendation is to use a clflush on the monitored address just before monitor and mwait pair [1]. This clflush makes sure that there are no false wakeups from mwait when the monitored address was recently written to. [1] "MONITOR/MWAIT Recommendations for Intel Xeon Processor 7400 series" section in specification update document of 7400 series http://download.intel.com/design/xeon/specupdt/32033601.pdf Signed-off-by: Venkatesh Pallipadi Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/intel.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'arch/x86/kernel/cpu/intel.c') diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 430e5c38a544..24ff26a38ade 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -291,6 +291,9 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c) ds_init_intel(c); } + if (c->x86 == 6 && c->x86_model == 29 && cpu_has_clflush) + set_cpu_cap(c, X86_FEATURE_CLFLUSH_MONITOR); + #ifdef CONFIG_X86_64 if (c->x86 == 15) c->x86_cache_alignment = c->x86_clflush_size * 2; -- cgit v1.2.3 From 7b6aa335ca1a845c2262ec7a595b4521bca0f79d Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Tue, 17 Feb 2009 13:58:15 +0100 Subject: x86, apic: remove genapic.h Impact: cleanup Remove genapic.h and remove all references to it. Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/intel.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/kernel/cpu/intel.c') diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 1f137a87d4bd..290f92e2b7c6 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -24,7 +24,7 @@ #ifdef CONFIG_X86_LOCAL_APIC #include #include -#include +#include #endif static void __cpuinit early_init_intel(struct cpuinfo_x86 *c) -- cgit v1.2.3 From e641f5f525acb163ba71d92de79c9c7366deae03 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Tue, 17 Feb 2009 14:02:01 +0100 Subject: x86, apic: remove duplicate asm/apic.h inclusions Impact: cleanup Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/intel.c | 1 - 1 file changed, 1 deletion(-) (limited to 'arch/x86/kernel/cpu/intel.c') diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 290f92e2b7c6..7aeef1d327b1 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -24,7 +24,6 @@ #ifdef CONFIG_X86_LOCAL_APIC #include #include -#include #endif static void __cpuinit early_init_intel(struct cpuinfo_x86 *c) -- cgit v1.2.3 From ecab22aa6dc9d42ca52de2cad0854b4c6bd85ac9 Mon Sep 17 00:00:00 2001 From: Vegard Nossum Date: Fri, 20 Feb 2009 11:56:38 +0100 Subject: x86: use symbolic constants for MSR_IA32_MISC_ENABLE bits Impact: Cleanup. No functional changes. Signed-off-by: Vegard Nossum Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/intel.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/x86/kernel/cpu/intel.c') diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 1f137a87d4bd..c8ff69a46681 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -147,10 +147,10 @@ static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c) */ if ((c->x86 == 15) && (c->x86_model == 1) && (c->x86_mask == 1)) { rdmsr(MSR_IA32_MISC_ENABLE, lo, hi); - if ((lo & (1<<9)) == 0) { + 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 |= (1<<9); /* Disable hw prefetching */ + lo |= MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE; wrmsr (MSR_IA32_MISC_ENABLE, lo, hi); } } -- cgit v1.2.3 From 1f442d70c84aa798e243e721eba728a98434cd86 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Sat, 7 Mar 2009 23:46:26 -0800 Subject: x86: remove smp_apply_quirks()/smp_checks() Impact: cleanup and code size reduction on 64-bit This code is only applied to Intel Pentium and AMD K7 32-bit cpus. Move those checks to intel_init()/amd_init() for 32-bit so 64-bit will not build this code. Also change to use cpu_index check to see if we need to emit warning. Signed-off-by: Yinghai Lu LKML-Reference: <49B377D2.8030108@kernel.org> Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/intel.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'arch/x86/kernel/cpu/intel.c') diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 25c559ba8d54..191117f1ad51 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -13,6 +13,7 @@ #include #include #include +#include #ifdef CONFIG_X86_64 #include @@ -110,6 +111,28 @@ static void __cpuinit trap_init_f00f_bug(void) } #endif +static void __cpuinit intel_smp_check(struct cpuinfo_x86 *c) +{ +#ifdef CONFIG_SMP + /* calling is from identify_secondary_cpu() ? */ + if (c->cpu_index == boot_cpu_id) + return; + + /* + * Mask B, Pentium, but not Pentium MMX + */ + if (c->x86 == 5 && + c->x86_mask >= 1 && c->x86_mask <= 4 && + c->x86_model <= 3) { + /* + * Remember we have B step Pentia with bugs + */ + WARN_ONCE(1, "WARNING: SMP operation may be unreliable" + "with B stepping processors.\n"); + } +#endif +} + static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c) { unsigned long lo, hi; @@ -186,6 +209,8 @@ static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c) #ifdef CONFIG_X86_NUMAQ numaq_tsc_disable(); #endif + + intel_smp_check(c); } #else static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c) -- cgit v1.2.3