From a449c7aa51e10c9bde0ea9bee4e682d6d067ebab Mon Sep 17 00:00:00 2001 From: Nadav Amit Date: Wed, 18 Jun 2014 17:19:24 +0300 Subject: [PATCH] KVM: x86: Hypercall handling does not considers opsize correctly Currently, the hypercall handling routine only considers LME as an indication to whether the guest uses 32/64-bit mode. This is incosistent with hyperv hypercalls handling and against the common sense of considering cs.l as well. This patch uses is_64_bit_mode instead of is_long_mode for that matter. In addition, the result is masked in respect to the guest execution mode. Last, it changes kvm_hv_hypercall to use is_64_bit_mode as well to simplify the code. Signed-off-by: Nadav Amit Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 451d6acea808..874607ae0583 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5669,7 +5669,6 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu) u64 param, ingpa, outgpa, ret; uint16_t code, rep_idx, rep_cnt, res = HV_STATUS_SUCCESS, rep_done = 0; bool fast, longmode; - int cs_db, cs_l; /* * hypercall generates UD from non zero cpl and real mode @@ -5680,8 +5679,7 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu) return 0; } - kvm_x86_ops->get_cs_db_l_bits(vcpu, &cs_db, &cs_l); - longmode = is_long_mode(vcpu) && cs_l == 1; + longmode = is_64_bit_mode(vcpu); if (!longmode) { param = ((u64)kvm_register_read(vcpu, VCPU_REGS_RDX) << 32) | @@ -5746,7 +5744,7 @@ static void kvm_pv_kick_cpu_op(struct kvm *kvm, unsigned long flags, int apicid) int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) { unsigned long nr, a0, a1, a2, a3, ret; - int r = 1; + int op_64_bit, r = 1; if (kvm_hv_hypercall_enabled(vcpu->kvm)) return kvm_hv_hypercall(vcpu); @@ -5759,7 +5757,8 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) trace_kvm_hypercall(nr, a0, a1, a2, a3); - if (!is_long_mode(vcpu)) { + op_64_bit = is_64_bit_mode(vcpu); + if (!op_64_bit) { nr &= 0xFFFFFFFF; a0 &= 0xFFFFFFFF; a1 &= 0xFFFFFFFF; @@ -5785,6 +5784,8 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) break; } out: + if (!op_64_bit) + ret = (u32)ret; kvm_register_write(vcpu, VCPU_REGS_RAX, ret); ++vcpu->stat.hypercalls; return r; -- 2.20.1