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Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/kernel/cpu/common.c3
-rw-r--r--arch/x86/kernel/head_64.S8
-rw-r--r--arch/x86/kernel/setup.c8
-rw-r--r--arch/x86/kernel/verify_cpu.S12
4 files changed, 24 insertions, 7 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 564140155c36..81e0fe48b9b0 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -280,10 +280,9 @@ __setup("nosmap", setup_disable_smap);
static __always_inline void setup_smap(struct cpuinfo_x86 *c)
{
- unsigned long eflags;
+ unsigned long eflags = native_save_fl();
/* This should have been cleared long ago */
- raw_local_save_flags(eflags);
BUG_ON(eflags & X86_EFLAGS_AC);
if (cpu_has(c, X86_FEATURE_SMAP)) {
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index f2a9a2aa98f3..3280489905a8 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/setup.c b/arch/x86/kernel/setup.c
index a3627ade4b15..e4baa389ee50 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -1156,6 +1156,14 @@ void __init setup_arch(char **cmdline_p)
clone_pgd_range(initial_page_table + KERNEL_PGD_BOUNDARY,
swapper_pg_dir + KERNEL_PGD_BOUNDARY,
KERNEL_PGD_PTRS);
+
+ /*
+ * sync back low identity map too. It is used for example
+ * in the 32-bit EFI stub.
+ */
+ clone_pgd_range(initial_page_table,
+ swapper_pg_dir + KERNEL_PGD_BOUNDARY,
+ min(KERNEL_PGD_PTRS, KERNEL_PGD_BOUNDARY));
#endif
tboot_probe();
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