[PATCH 2/2] x86: detect scattered cpuid features earlier

Colin King colin.king at canonical.com
Wed Oct 6 14:46:05 UTC 2010

From: Jacob Pan <jacob.jun.pan at linux.intel.com>

BugLink: http://bugs.launchpad.net/bugs/615153

Some extra CPU features such as ARAT is needed in early boot so
that x86_init function pointers can be set up properly.
At start_kernel() level, this patch moves init_scattered_cpuid_features()
from check_bugs() to setup_arch() -> early_cpu_init() which is earlier than
platform specific x86_init layer setup. Suggested by HPA.

Signed-off-by: Jacob Pan <jacob.jun.pan at linux.intel.com>
LKML-Reference: <1274295685-6774-2-git-send-email-jacob.jun.pan at linux.intel.com>
Acked-by: Thomas Gleixner <tglx at linutronix.de>
Signed-off-by: H. Peter Anvin <hpa at linux.intel.com>
Signed-off-by: Colin Ian King <colin.king at canonical.com>
 arch/x86/kernel/cpu/common.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 8962fc7..2743295 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -576,6 +576,7 @@ void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
 	if (c->extended_cpuid_level >= 0x80000007)
 		c->x86_power = cpuid_edx(0x80000007);
+	init_scattered_cpuid_features(c);
 static void __cpuinit identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
@@ -731,7 +732,6 @@ static void __cpuinit generic_identify(struct cpuinfo_x86 *c)
 	get_model_name(c); /* Default name */
-	init_scattered_cpuid_features(c);

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