From f20d2752980c144c82649eb18746ef0c29f508dd Mon Sep 17 00:00:00 2001 From: Jes Sorensen Date: Tue, 20 May 2008 13:13:50 +0200 Subject: [PATCH] KVM: ia64: fix zero extending for mmio ld1/2/4 emulation in KVM Only copy in the data actually requested by the instruction emulation and zero pad the destination register first. This avoids the problem where emulated mmio access got garbled data from ld2.acq instructions in the vga console driver. Signed-off-by: Jes Sorensen Acked-by: Xiantao Zhang Signed-off-by: Avi Kivity --- arch/ia64/kvm/mmio.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/ia64/kvm/mmio.c b/arch/ia64/kvm/mmio.c index 351bf70da46..7f1a858bc69 100644 --- a/arch/ia64/kvm/mmio.c +++ b/arch/ia64/kvm/mmio.c @@ -159,7 +159,8 @@ static void mmio_access(struct kvm_vcpu *vcpu, u64 src_pa, u64 *dest, if (p->u.ioreq.state == STATE_IORESP_READY) { if (dir == IOREQ_READ) - *dest = p->u.ioreq.data; + /* it's necessary to ensure zero extending */ + *dest = p->u.ioreq.data & (~0UL >> (64-(s*8))); } else panic_vm(vcpu); out: -- 2.41.1