diff options
| author | Ingo Molnar <mingo@elte.hu> | 2010-04-30 09:56:41 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2010-04-30 09:56:44 +0200 |
| commit | 3ca50496c2677a2b3fdd3ede86660fd1433beac6 (patch) | |
| tree | 97a76d8479a8d8a96e04ed0694b8dbf89457bfcc /arch/x86/kernel/cpu/intel.c | |
| parent | 462b04e28a7ec1339c892117c3f20a40e55d0e83 (diff) | |
| parent | 66f41d4c5c8a5deed66fdcc84509376c9a0bf9d8 (diff) | |
Merge commit 'v2.6.34-rc6' into perf/core
Merge reason: update to the latest -rc.
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 | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index d72377c41c7..f5e5390d345 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -46,6 +46,27 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c) (c->x86 == 0x6 && c->x86_model >= 0x0e)) set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC); + /* + * Atom erratum AAE44/AAF40/AAG38/AAH41: + * + * A race condition between speculative fetches and invalidating + * a large page. This is worked around in microcode, but we + * need the microcode to have already been loaded... so if it is + * not, recommend a BIOS update and disable large pages. + */ + if (c->x86 == 6 && c->x86_model == 0x1c && c->x86_mask <= 2) { + u32 ucode, junk; + + wrmsr(MSR_IA32_UCODE_REV, 0, 0); + sync_core(); + rdmsr(MSR_IA32_UCODE_REV, junk, ucode); + + if (ucode < 0x20e) { + printk(KERN_WARNING "Atom PSE erratum detected, BIOS microcode update recommended\n"); + clear_cpu_cap(c, X86_FEATURE_PSE); + } + } + #ifdef CONFIG_X86_64 set_cpu_cap(c, X86_FEATURE_SYSENTER32); #else |