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-rw-r--r--arch/x86/kernel/head_64.S8
-rw-r--r--arch/x86/kernel/verify_cpu.S12
2 files changed, 15 insertions, 5 deletions
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 7e5da2cbe59e..174fa035a09a 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -65,6 +65,9 @@ startup_64:
* tables and then reload them.
*/
+ /* Sanitize CPU configuration */
+ call verify_cpu
+
/*
* Compute the delta between the address I am compiled to run at and the
* address I am actually running at.
@@ -174,6 +177,9 @@ ENTRY(secondary_startup_64)
* after the boot processor executes this code.
*/
+ /* Sanitize CPU configuration */
+ call verify_cpu
+
movq $(init_level4_pgt - __START_KERNEL_map), %rax
1:
@@ -288,6 +294,8 @@ ENTRY(secondary_startup_64)
pushq %rax # target address in negative space
lretq
+#include "verify_cpu.S"
+
#ifdef CONFIG_HOTPLUG_CPU
/*
* Boot CPU0 entry point. It's called from play_dead(). Everything has been set
diff --git a/arch/x86/kernel/verify_cpu.S b/arch/x86/kernel/verify_cpu.S
index b9242bacbe59..4cf401f581e7 100644
--- a/arch/x86/kernel/verify_cpu.S
+++ b/arch/x86/kernel/verify_cpu.S
@@ -34,10 +34,11 @@
#include <asm/msr-index.h>
verify_cpu:
- pushfl # Save caller passed flags
- pushl $0 # Kill any dangerous flags
- popfl
+ pushf # Save caller passed flags
+ push $0 # Kill any dangerous flags
+ popf
+#ifndef __x86_64__
pushfl # standard way to check for cpuid
popl %eax
movl %eax,%ebx
@@ -48,6 +49,7 @@ verify_cpu:
popl %eax
cmpl %eax,%ebx
jz verify_cpu_no_longmode # cpu has no cpuid
+#endif
movl $0x0,%eax # See if cpuid 1 is implemented
cpuid
@@ -130,10 +132,10 @@ verify_cpu_sse_test:
jmp verify_cpu_sse_test # try again
verify_cpu_no_longmode:
- popfl # Restore caller passed flags
+ popf # Restore caller passed flags
movl $1,%eax
ret
verify_cpu_sse_ok:
- popfl # Restore caller passed flags
+ popf # Restore caller passed flags
xorl %eax, %eax
ret