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Diffstat (limited to 'arch/x86/kernel/cpu/common.c')
-rw-r--r--arch/x86/kernel/cpu/common.c18
1 files changed, 16 insertions, 2 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 80ab20d4fa39..4e456bd955bb 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -13,6 +13,7 @@
#include <asm/mtrr.h>
#include <asm/mce.h>
#include <asm/pat.h>
+#include <asm/asm.h>
#ifdef CONFIG_X86_LOCAL_APIC
#include <asm/mpspec.h>
#include <asm/apic.h>
@@ -334,11 +335,24 @@ static void __init early_cpu_detect(void)
get_cpu_vendor(c, 1);
+ early_get_cap(c);
+
if (c->x86_vendor != X86_VENDOR_UNKNOWN &&
cpu_devs[c->x86_vendor]->c_early_init)
cpu_devs[c->x86_vendor]->c_early_init(c);
+}
- early_get_cap(c);
+/*
+ * The NOPL instruction is supposed to exist on all CPUs with
+ * family >= 6; unfortunately, that's not true in practice because
+ * of early VIA chips and (more importantly) broken virtualizers that
+ * are not easy to detect. In the latter case it doesn't even *fail*
+ * reliably, so probing for it doesn't even work. Disable it completely
+ * unless we can find a reliable way to detect all the broken cases.
+ */
+static void __cpuinit detect_nopl(struct cpuinfo_x86 *c)
+{
+ clear_cpu_cap(c, X86_FEATURE_NOPL);
}
static void __cpuinit generic_identify(struct cpuinfo_x86 *c)
@@ -395,8 +409,8 @@ static void __cpuinit generic_identify(struct cpuinfo_x86 *c)
}
init_scattered_cpuid_features(c);
+ detect_nopl(c);
}
-
}
static void __cpuinit squash_the_stupid_serial_number(struct cpuinfo_x86 *c)