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authorYinghai Lu <yinghai@kernel.org>2009-05-09 23:47:42 -0700
committerIngo Molnar <mingo@elte.hu>2009-05-11 10:57:24 +0200
commit3e0c373749d7eb5b354ac0b043f2b2cdf84eefef (patch)
tree473870b2f527ce227cb729db35dbe226ce95a7d1 /arch/x86
parent3969c52d4d2fef5a4b9e3ab0e51b3901e1cc8b83 (diff)
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 <hpa@linux.intel.com> Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Yinghai Lu <yinghai.lu@kernel.org> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/include/asm/cpufeature.h4
-rw-r--r--arch/x86/include/asm/processor.h3
-rw-r--r--arch/x86/kernel/cpu/common.c17
3 files changed, 16 insertions, 8 deletions
diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
index ccc1061b8b2..13cc6a503a0 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 c2cceae709c..fed93fec976 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 c4f667896c2..e7fd5c4935a 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);