diff --git a/arch/x86/boot/pmjump.S b/arch/x86/boot/pmjump.S
index 26baeab3a4d4e68f2a0d222732998d696521a9ec..fa6bed1fac14862b86936f1bc45af5c9b64aa7cf 100644
--- a/arch/x86/boot/pmjump.S
+++ b/arch/x86/boot/pmjump.S
@@ -28,11 +28,13 @@
  * 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
 
 	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