[PATCH 4.14 45/47] KVM: SVM: Truncate GPR value for DR and CR accesses in !64-bit mode
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-06-08 18:35:41
Also in:
lkml
From: Sean Christopherson <seanjc@google.com>
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 <seanjc@google.com>
Message-Id: [off-list ref]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[sudip: manual backport to old file]
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/x86/kvm/svm.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c@@ -3532,7 +3532,7 @@ static int cr_interception(struct vcpu_s err = 0; if (cr >= 16) { /* mov to cr */ cr -= 16; - val = kvm_register_read(&svm->vcpu, reg); + val = kvm_register_readl(&svm->vcpu, reg); switch (cr) { case 0: if (!check_selective_cr0_intercepted(svm, val))
@@ -3577,7 +3577,7 @@ static int cr_interception(struct vcpu_s kvm_queue_exception(&svm->vcpu, UD_VECTOR); return 1; } - kvm_register_write(&svm->vcpu, reg, val); + kvm_register_writel(&svm->vcpu, reg, val); } return kvm_complete_insn_gp(&svm->vcpu, err); }
@@ -3607,13 +3607,13 @@ static int dr_interception(struct vcpu_s 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);