4 files changed, 22 insertions, 16 deletions

diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c
index 81e5ab6542d8..426e5d91b63a 100644
--- a/arch/x86/kernel/acpi/sleep.c
+++ b/arch/x86/kernel/acpi/sleep.c
@@ -86,7 +86,7 @@ int acpi_save_state_mem(void)
 #endif /* !CONFIG_64BIT */
 
         header->pmode_cr0 = read_cr0();
-        header->pmode_cr4 = read_cr4();
+        header->pmode_cr4 = read_cr4_safe();
         header->realmode_flags = acpi_realmode_flags;
         header->real_magic = 0x12345678;
 
diff --git a/arch/x86/kernel/efi_32.c b/arch/x86/kernel/efi_32.c
index 4b63c8e1f13b..5cab48ee61a4 100644
--- a/arch/x86/kernel/efi_32.c
+++ b/arch/x86/kernel/efi_32.c
@@ -53,7 +53,7 @@ void efi_call_phys_prelog(void)
          * directory. If I have PAE, I just need to duplicate one entry in
          * page directory.
          */
-        cr4 = read_cr4();
+        cr4 = read_cr4_safe();
 
         if (cr4 & X86_CR4_PAE) {
                 efi_bak_pg_dir_pointer[0].pgd =
@@ -91,7 +91,7 @@ void efi_call_phys_epilog(void)
         gdt_descr.size = GDT_SIZE - 1;
         load_gdt(&gdt_descr);
 
-        cr4 = read_cr4();
+        cr4 = read_cr4_safe();
 
         if (cr4 & X86_CR4_PAE) {
                 swapper_pg_dir[pgd_index(0)].pgd =
diff --git a/arch/x86/power/cpu_32.c b/arch/x86/power/cpu_32.c
index 7dc5d5cf50a2..d3e083dea720 100644
--- a/arch/x86/power/cpu_32.c
+++ b/arch/x86/power/cpu_32.c
@@ -45,7 +45,7 @@ static void __save_processor_state(struct saved_context *ctxt)
         ctxt->cr0 = read_cr0();
         ctxt->cr2 = read_cr2();
         ctxt->cr3 = read_cr3();
-        ctxt->cr4 = read_cr4();
+        ctxt->cr4 = read_cr4_safe();
 }
 
 /* Needed by apm.c */
@@ -98,7 +98,9 @@ static void __restore_processor_state(struct saved_context *ctxt)
         /*
          * control registers
          */
-        write_cr4(ctxt->cr4);
+        /* cr4 was introduced in the Pentium CPU */
+        if (ctxt->cr4)
+                write_cr4(ctxt->cr4);
         write_cr3(ctxt->cr3);
         write_cr2(ctxt->cr2);
         write_cr0(ctxt->cr0);
diff --git a/arch/x86/power/hibernate_asm_32.S b/arch/x86/power/hibernate_asm_32.S
index b95aa6cfe3cb..4fc7e872c85e 100644
--- a/arch/x86/power/hibernate_asm_32.S
+++ b/arch/x86/power/hibernate_asm_32.S
@@ -28,9 +28,9 @@ ENTRY(swsusp_arch_suspend)
         ret
 
 ENTRY(restore_image)
-        movl    resume_pg_dir, %ecx
-        subl    $__PAGE_OFFSET, %ecx
-        movl    %ecx, %cr3
+        movl    resume_pg_dir, %eax
+        subl    $__PAGE_OFFSET, %eax
+        movl    %eax, %cr3
 
         movl    restore_pblist, %edx
         .p2align 4,,7
@@ -52,17 +52,21 @@ copy_loop:
 
 done:
         /* go back to the original page tables */
-        movl    $swapper_pg_dir, %ecx
-        subl    $__PAGE_OFFSET, %ecx
-        movl    %ecx, %cr3
+        movl    $swapper_pg_dir, %eax
+        subl    $__PAGE_OFFSET, %eax
+        movl    %eax, %cr3
         /* Flush TLB, including "global" things (vmalloc) */
-        movl    mmu_cr4_features, %eax
-        movl    %eax, %edx
+        movl    mmu_cr4_features, %ecx
+        jecxz   1f      # cr4 Pentium and higher, skip if zero
+        movl    %ecx, %edx
         andl    $~(1<<7), %edx;  # PGE
         movl    %edx, %cr4;  # turn off PGE
-        movl    %cr3, %ecx;  # flush TLB
-        movl    %ecx, %cr3
-        movl    %eax, %cr4;  # turn PGE back on
+1:
+        movl    %cr3, %eax;  # flush TLB
+        movl    %eax, %cr3
+        jecxz   1f      # cr4 Pentium and higher, skip if zero
+        movl    %ecx, %cr4;  # turn PGE back on
+1:
 
         movl saved_context_esp, %esp
         movl saved_context_ebp, %ebp