Commit 15b00f32 authored Nov 19, 2007 by Jan Kiszka Committed by Avi Kivity Jan 30, 2008

KVM: VMX: Force seg.base == (seg.sel << 4) in real mode

Ensure that segment.base == segment.selector << 4 when entering the real
mode on Intel so that the CPU will not bark at us.  This fixes some old
protected mode demo from http://www.x86.org/articles/pmbasics/tspec_a1_doc.htm

.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

parent 54f1585a

drivers/kvm/vmx.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -1165,7 +1165,8 @@ static void fix_rmode_seg(int seg, struct kvm_save_segment *save)
		save->base = vmcs_readl(sf->base);
		save->limit = vmcs_read32(sf->limit);
		save->ar = vmcs_read32(sf->ar_bytes);
		vmcs_write16(sf->selector, vmcs_readl(sf->base) >> 4);
		vmcs_write16(sf->selector, save->base >> 4);
		vmcs_write32(sf->base, save->base & 0xfffff);
		vmcs_write32(sf->limit, 0xffff);
		vmcs_write32(sf->ar_bytes, 0xf3);
		}

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