summaryrefslogtreecommitdiffstats
path: root/arch/x86/boot/pmjump.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/boot/pmjump.S')
-rw-r--r--arch/x86/boot/pmjump.S8
1 files changed, 5 insertions, 3 deletions
diff --git a/arch/x86/boot/pmjump.S b/arch/x86/boot/pmjump.S
index 2e559233725a..fa6bed1fac14 100644
--- a/arch/x86/boot/pmjump.S
+++ b/arch/x86/boot/pmjump.S
@@ -28,17 +28,19 @@
* void protected_mode_jump(u32 entrypoint, u32 bootparams);
*/
protected_mode_jump:
- xorl %ebx, %ebx # Flag to indicate this is a boot
movl %edx, %esi # Pointer to boot_params table
movl %eax, 2f # Patch ljmpl instruction
- jmp 1f # Short jump to flush instruction q.
-1:
movw $__BOOT_DS, %cx
+ xorl %ebx, %ebx # Per the 32-bit boot protocol
+ xorl %ebp, %ebp # Per the 32-bit boot protocol
+ xorl %edi, %edi # Per the 32-bit boot protocol
movl %cr0, %edx
orb $1, %dl # Protected mode (PE) bit
movl %edx, %cr0
+ jmp 1f # Short jump to serialize on 386/486
+1:
movw %cx, %ds
movw %cx, %es
OpenPOWER on IntegriCloud