Commit dcab9753 authored by H. Peter Anvin's avatar H. Peter Anvin Committed by Greg Kroah-Hartman

x86 setup: add a near jump to serialize %cr0 on 386/486

patch 7ed19290 in mainline.

The 386 and 486 needs a jump immediately after setting %cr0 in order
to serialize the pipeline.
Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 0fe8f9b2
......@@ -31,14 +31,14 @@ 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
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
......
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