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

H. Peter Anvin · H. Peter Anvin · commit d900329e20f4 · 2010-09-28T16:33:14.000-07:00
After uncapping the CPUID level, we need to also re-run the CPU
feature detection code.

This resolves kernel bugzilla 16322.

Reported-by: boris64 &lt;bugzilla.kernel.org@boris64.net&gt;
Cc: &lt;stable@kernel.org&gt; v2.6.29..2.6.35
LKML-Reference: &lt;tip-@git.kernel.org&gt;
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
@@ -545,7 +545,7 @@ 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;
diff --git a/arch/x86/kernel/cpu/cpu.h b/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 cpu_detect_cache_sizes(struct cpuinfo_x86 *c);
+extern void get_cpu_cap(struct cpuinfo_x86 *c);
 
 #endif
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
@@ -39,6 +39,7 @@ 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);
 		}
 	}
 

Original file line number	Diff line number	Diff line change
`@@ -545,7 +545,7 @@ void __cpuinit cpu_detect(struct cpuinfo_x86 *c)`
`545`	`545`	`}`
`546`	`546`	`}`
`547`	`547`
`548`		`-static void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)`
	`548`	`+void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)`
`549`	`549`	`{`
`550`	`550`	`u32 tfms, xlvl;`
`551`	`551`	`u32 ebx;`
Original file line number	Diff line number	Diff line change
`@@ -39,6 +39,7 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c)`
`39`	`39`	`misc_enable &= ~MSR_IA32_MISC_ENABLE_LIMIT_CPUID;`
`40`	`40`	`wrmsrl(MSR_IA32_MISC_ENABLE, misc_enable);`
`41`	`41`	`c->cpuid_level = cpuid_eax(0);`
	`42`	`+ get_cpu_cap(c);`
`42`	`43`	`}`
`43`	`44`	`}`
`44`	`45`