>From 193d4aab68376c85d4bcf59ff96e248b9f84836f Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Wed, 21 Apr 2021 19:21:22 -0700 Subject: [PATCH] KVM: SVM: Truncate GPR value for DR and CR accesses in !64-bit mode commit 0884335a2e653b8a045083aa1d57ce74269ac81d upstream. Drop bits 63:32 on loads/stores to/from DRs and CRs when the vCPU is not in 64-bit mode. The APM states bits 63:32 are dropped for both DRs and CRs: In 64-bit mode, the operand size is fixed at 64 bits without the need for a REX prefix. In non-64-bit mode, the operand size is fixed at 32 bits and the upper 32 bits of the destination are forced to 0. Fixes: 7ff76d58a9dc ("KVM: SVM: enhance MOV CR intercept handler") Fixes: cae3797a4639 ("KVM: SVM: enhance mov DR intercept handler") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson Message-Id: <20210422022128.3464144-4-seanjc@google.com> Signed-off-by: Paolo Bonzini Signed-off-by: Sudip Mukherjee --- arch/x86/kvm/svm/svm.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 9d4eb114613c..41d44fb5f753 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -2362,7 +2362,7 @@ static int cr_interception(struct vcpu_svm *svm) err = 0; if (cr >= 16) { /* mov to cr */ cr -= 16; - val = kvm_register_read(&svm->vcpu, reg); + val = kvm_register_readl(&svm->vcpu, reg); trace_kvm_cr_write(cr, val); switch (cr) { case 0: @@ -2408,7 +2408,7 @@ static int cr_interception(struct vcpu_svm *svm) kvm_queue_exception(&svm->vcpu, UD_VECTOR); return 1; } - kvm_register_write(&svm->vcpu, reg, val); + kvm_register_writel(&svm->vcpu, reg, val); trace_kvm_cr_read(cr, val); } return kvm_complete_insn_gp(&svm->vcpu, err); @@ -2439,13 +2439,13 @@ static int dr_interception(struct vcpu_svm *svm) if (dr >= 16) { /* mov to DRn */ if (!kvm_require_dr(&svm->vcpu, dr - 16)) return 1; - val = kvm_register_read(&svm->vcpu, reg); + val = kvm_register_readl(&svm->vcpu, reg); kvm_set_dr(&svm->vcpu, dr - 16, val); } else { if (!kvm_require_dr(&svm->vcpu, dr)) return 1; kvm_get_dr(&svm->vcpu, dr, &val); - kvm_register_write(&svm->vcpu, reg, val); + kvm_register_writel(&svm->vcpu, reg, val); } return kvm_skip_emulated_instruction(&svm->vcpu); -- 2.30.2