From: Andi Kleen commit d3f7eae182b04997be19343a23f7009170f4f7a5 upstream The Averatec 2370 and some other Turion laptop BIOS seems to program the ENABLE_C1E MSR inconsistently between cores. This confuses the lapic use heuristics because when C1E is enabled anywhere it seems to affect the complete chip. Use a global flag instead of a per cpu flag to handle this. If any CPU has C1E enabled disabled lapic use. Thanks to Cal Peake for debugging. Cc: tglx@linutronix.de Cc: Chuck Ebbert Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- arch/i386/kernel/apic.c | 10 ++++------ arch/i386/kernel/cpu/amd.c | 7 ++++++- include/asm-i386/apic.h | 2 ++ include/asm-i386/cpufeature.h | 2 +- 4 files changed, 13 insertions(+), 8 deletions(-) --- a/arch/i386/kernel/apic.c +++ b/arch/i386/kernel/apic.c @@ -61,8 +61,9 @@ static int enable_local_apic __initdata /* Local APIC timer verification ok */ static int local_apic_timer_verify_ok; -/* Disable local APIC timer from the kernel commandline or via dmi quirk */ -static int local_apic_timer_disabled; +/* Disable local APIC timer from the kernel commandline or via dmi quirk + or using CPU MSR check */ +int local_apic_timer_disabled; /* Local APIC timer works in C2 */ int local_apic_timer_c2_ok; EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok); @@ -367,12 +368,9 @@ void __init setup_boot_APIC_clock(void) long delta, deltapm; int pm_referenced = 0; - if (boot_cpu_has(X86_FEATURE_LAPIC_TIMER_BROKEN)) - local_apic_timer_disabled = 1; - /* * The local apic timer can be disabled via the kernel - * commandline or from the test above. Register the lapic + * commandline or from the CPU detection code. Register the lapic * timer as a dummy clock event source on SMP systems, so the * broadcast mechanism is used. On UP systems simply ignore it. */ --- a/arch/i386/kernel/cpu/amd.c +++ b/arch/i386/kernel/cpu/amd.c @@ -3,6 +3,7 @@ #include #include #include +#include #include "cpu.h" @@ -22,6 +23,7 @@ extern void vide(void); __asm__(".align 4\nvide: ret"); +#ifdef CONFIG_X86_LOCAL_APIC #define ENABLE_C1E_MASK 0x18000000 #define CPUID_PROCESSOR_SIGNATURE 1 #define CPUID_XFAM 0x0ff00000 @@ -52,6 +54,7 @@ static __cpuinit int amd_apic_timer_brok } return 0; } +#endif int force_mwait __cpuinitdata; @@ -275,8 +278,10 @@ static void __cpuinit init_amd(struct cp if (cpuid_eax(0x80000000) >= 0x80000006) num_cache_leaves = 3; +#ifdef CONFIG_X86_LOCAL_APIC if (amd_apic_timer_broken()) - set_bit(X86_FEATURE_LAPIC_TIMER_BROKEN, c->x86_capability); + local_apic_timer_disabled = 1; +#endif if (c->x86 == 0x10 && !force_mwait) clear_bit(X86_FEATURE_MWAIT, c->x86_capability); --- a/include/asm-i386/apic.h +++ b/include/asm-i386/apic.h @@ -116,6 +116,8 @@ extern void enable_NMI_through_LVT0 (voi extern int timer_over_8254; extern int local_apic_timer_c2_ok; +extern int local_apic_timer_disabled; + #else /* !CONFIG_X86_LOCAL_APIC */ static inline void lapic_shutdown(void) { } --- a/include/asm-i386/cpufeature.h +++ b/include/asm-i386/cpufeature.h @@ -79,7 +79,7 @@ #define X86_FEATURE_ARCH_PERFMON (3*32+11) /* Intel Architectural PerfMon */ #define X86_FEATURE_PEBS (3*32+12) /* Precise-Event Based Sampling */ #define X86_FEATURE_BTS (3*32+13) /* Branch Trace Store */ -#define X86_FEATURE_LAPIC_TIMER_BROKEN (3*32+ 14) /* lapic timer broken in C1 */ +/* 14 free */ #define X86_FEATURE_SYNC_RDTSC (3*32+15) /* RDTSC synchronizes the CPU */ /* Intel-defined CPU features, CPUID level 0x00000001 (ecx), word 4 */ -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/