diff options
| author | Ingo Molnar <mingo@elte.hu> | 2009-06-17 13:06:17 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-06-17 13:06:17 +0200 |
| commit | a3d06cc6aa3e765dc2bf98626f87272dcf641dca (patch) | |
| tree | aa3e49b58f08d6c0ea55cdca4fb5e6c8ba6ae333 /arch/x86/kernel/cpu/intel.c | |
| parent | 0990b1c65729012a63e0eeca93aaaafea4e9a064 (diff) | |
| parent | 65795efbd380a832ae508b04dba8f8e53f0b84d9 (diff) | |
Merge branch 'linus' into perfcounters/core
Conflicts:
arch/x86/include/asm/kmap_types.h
include/linux/mm.h
include/asm-generic/kmap_types.h
Merge reason: We crossed changes with kmap_types.h cleanups in mainline.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel/cpu/intel.c')
| -rw-r--r-- | arch/x86/kernel/cpu/intel.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index daed39ba261..3260ab04499 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -86,6 +86,29 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c) */ if (c->x86 == 6 && c->x86_model < 15) clear_cpu_cap(c, X86_FEATURE_PAT); + +#ifdef CONFIG_KMEMCHECK + /* + * P4s have a "fast strings" feature which causes single- + * stepping REP instructions to only generate a #DB on + * cache-line boundaries. + * + * Ingo Molnar reported a Pentium D (model 6) and a Xeon + * (model 2) with the same problem. + */ + if (c->x86 == 15) { + u64 misc_enable; + + 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); + } + } +#endif } #ifdef CONFIG_X86_32 |