From 3e0c373749d7eb5b354ac0b043f2b2cdf84eefef Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Sat, 9 May 2009 23:47:42 -0700 Subject: [PATCH] x86: clean up and fix setup_clear/force_cpu_cap handling setup_force_cpu_cap() only have one user (Xen guest code), but it should not reuse cleared_cpu_cpus, otherwise it will have problems on SMP. Need to have a separate cpu_cpus_set array too, for forced-on flags, beyond the forced-off flags. Also need to setup handling before all cpus caps are combined. [ Impact: fix the forced-set CPU feature flag logic ] Cc: H. Peter Anvin Cc: Jeremy Fitzhardinge Cc: Rusty Russell Signed-off-by: Yinghai Lu LKML-Reference: Signed-off-by: Ingo Molnar --- arch/x86/include/asm/cpufeature.h | 4 ++-- arch/x86/include/asm/processor.h | 3 ++- arch/x86/kernel/cpu/common.c | 17 ++++++++++++----- 3 files changed, 16 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index ccc1061b8b25..13cc6a503a02 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -192,11 +192,11 @@ extern const char * const x86_power_flags[32]; #define clear_cpu_cap(c, bit) clear_bit(bit, (unsigned long *)((c)->x86_capability)) #define setup_clear_cpu_cap(bit) do { \ clear_cpu_cap(&boot_cpu_data, bit); \ - set_bit(bit, (unsigned long *)cleared_cpu_caps); \ + set_bit(bit, (unsigned long *)cpu_caps_cleared); \ } while (0) #define setup_force_cpu_cap(bit) do { \ set_cpu_cap(&boot_cpu_data, bit); \ - clear_bit(bit, (unsigned long *)cleared_cpu_caps); \ + set_bit(bit, (unsigned long *)cpu_caps_set); \ } while (0) #define cpu_has_fpu boot_cpu_has(X86_FEATURE_FPU) diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index c2cceae709c8..fed93fec9764 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -135,7 +135,8 @@ extern struct cpuinfo_x86 boot_cpu_data; extern struct cpuinfo_x86 new_cpu_data; extern struct tss_struct doublefault_tss; -extern __u32 cleared_cpu_caps[NCAPINTS]; +extern __u32 cpu_caps_cleared[NCAPINTS]; +extern __u32 cpu_caps_set[NCAPINTS]; #ifdef CONFIG_SMP DECLARE_PER_CPU_SHARED_ALIGNED(struct cpuinfo_x86, cpu_info); diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index c4f667896c28..e7fd5c4935a3 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -292,7 +292,8 @@ static const char *__cpuinit table_lookup_model(struct cpuinfo_x86 *c) return NULL; /* Not found */ } -__u32 cleared_cpu_caps[NCAPINTS] __cpuinitdata; +__u32 cpu_caps_cleared[NCAPINTS] __cpuinitdata; +__u32 cpu_caps_set[NCAPINTS] __cpuinitdata; void load_percpu_segment(int cpu) { @@ -806,6 +807,16 @@ static void __cpuinit identify_cpu(struct cpuinfo_x86 *c) #endif init_hypervisor(c); + + /* + * Clear/Set all flags overriden by options, need do it + * before following smp all cpus cap AND. + */ + for (i = 0; i < NCAPINTS; i++) { + c->x86_capability[i] &= ~cpu_caps_cleared[i]; + c->x86_capability[i] |= cpu_caps_set[i]; + } + /* * On SMP, boot_cpu_data holds the common feature set between * all CPUs; so make sure that we indicate which features are @@ -818,10 +829,6 @@ static void __cpuinit identify_cpu(struct cpuinfo_x86 *c) boot_cpu_data.x86_capability[i] &= c->x86_capability[i]; } - /* Clear all flags overriden by options */ - for (i = 0; i < NCAPINTS; i++) - c->x86_capability[i] &= ~cleared_cpu_caps[i]; - #ifdef CONFIG_X86_MCE /* Init Machine Check Exception if available. */ mcheck_init(c); -- GitLab