x86, cpu: After uncapping CPUID, re-run CPU feature detection

commit d900329e upstream.

After uncapping the CPUID level, we need to also re-run the CPU
feature detection code.

This resolves kernel bugzilla 16322.
Reported-by: boris64 <bugzilla.kernel.org@boris64.net>
LKML-Reference: <tip-@git.kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

arch/x86/kernel/cpu/common.c

@@ -540,7 +540,7 @@ void __cpuinit cpu_detect(struct cpuinfo_x86 *c)
 	}
 }
 
-static void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
+void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
 {
 	u32 tfms, xlvl;
 	u32 ebx;

arch/x86/kernel/cpu/cpu.h

@@ -33,5 +33,6 @@ extern const struct cpu_dev *const __x86_cpu_dev_start[],
 			    *const __x86_cpu_dev_end[];
 
 extern void display_cacheinfo(struct cpuinfo_x86 *c);
+extern void get_cpu_cap(struct cpuinfo_x86 *c);
 
 #endif

arch/x86/kernel/cpu/intel.c

@@ -40,6 +40,7 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c)
 			misc_enable &= ~MSR_IA32_MISC_ENABLE_LIMIT_CPUID;
 			wrmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
 			c->cpuid_level = cpuid_eax(0);
+			get_cpu_cap(c);
 		}
 	}