diff options
| author | Jan Kiszka <jan.kiszka@siemens.com> | 2014-06-30 10:54:17 +0200 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2014-07-09 18:09:55 +0200 |
| commit | 9bf418335e24da995ea682a028926d7e1036be6f (patch) | |
| tree | 2744a9564a101286b60272ff7eff4c216326d19c /arch/x86/kvm/svm.c | |
| parent | 62baf44cad3bc6b37115cc21e4228fe53d4f3474 (diff) | |
| download | linux-9bf418335e24da995ea682a028926d7e1036be6f.tar.bz2 | |
KVM: nSVM: Fix IOIO bitmap evaluation
First, kvm_read_guest returns 0 on success. And then we need to take the
access size into account when testing the bitmap: intercept if any of
bits corresponding to the access is set.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/svm.c')
| -rw-r--r-- | arch/x86/kvm/svm.c | 19 |
1 files changed, 12 insertions, 7 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index c79766e1f1e0..3483ac978c76 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -2116,22 +2116,27 @@ static void nested_svm_unmap(struct page *page) static int nested_svm_intercept_ioio(struct vcpu_svm *svm) { - unsigned port; - u8 val, bit; + unsigned port, size, iopm_len; + u16 val, mask; + u8 start_bit; u64 gpa; if (!(svm->nested.intercept & (1ULL << INTERCEPT_IOIO_PROT))) return NESTED_EXIT_HOST; port = svm->vmcb->control.exit_info_1 >> 16; + size = (svm->vmcb->control.exit_info_1 & SVM_IOIO_SIZE_MASK) >> + SVM_IOIO_SIZE_SHIFT; gpa = svm->nested.vmcb_iopm + (port / 8); - bit = port % 8; - val = 0; + start_bit = port % 8; + iopm_len = (start_bit + size > 8) ? 2 : 1; + mask = (0xf >> (4 - size)) << start_bit; + val = 0; - if (kvm_read_guest(svm->vcpu.kvm, gpa, &val, 1)) - val &= (1 << bit); + if (kvm_read_guest(svm->vcpu.kvm, gpa, &val, iopm_len)) + return NESTED_EXIT_DONE; - return val ? NESTED_EXIT_DONE : NESTED_EXIT_HOST; + return (val & mask) ? NESTED_EXIT_DONE : NESTED_EXIT_HOST; } static int nested_svm_exit_handled_msr(struct vcpu_svm *svm) |