diff options
| author | Alexander Graf <agraf@suse.de> | 2011-08-08 16:07:16 +0200 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2011-09-25 19:52:20 +0300 |
| commit | 317a8fa304f8ba3cd8b67b0f5f38e366e8c3cf1d (patch) | |
| tree | 874c27833a8dbaddce52f5313c7c6af41143369d /arch/powerpc | |
| parent | 9432ba6015371f186926cd62e2395718217a17a1 (diff) | |
KVM: PPC: Check privilege level on SPRs
We have 3 privilege levels: problem state, supervisor state and hypervisor
state. Each of them can access different SPRs, so we need to check on every
SPR if it's accessible in the respective mode.
Signed-off-by: Alexander Graf <agraf@suse.de>
Diffstat (limited to 'arch/powerpc')
| -rw-r--r-- | arch/powerpc/kvm/book3s_emulate.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_emulate.c b/arch/powerpc/kvm/book3s_emulate.c index 466846557089..bf0ddcd98bcc 100644 --- a/arch/powerpc/kvm/book3s_emulate.c +++ b/arch/powerpc/kvm/book3s_emulate.c @@ -63,6 +63,25 @@ * function pointers, so let's just disable the define. */ #undef mfsrin +enum priv_level { + PRIV_PROBLEM = 0, + PRIV_SUPER = 1, + PRIV_HYPER = 2, +}; + +static bool spr_allowed(struct kvm_vcpu *vcpu, enum priv_level level) +{ + /* PAPR VMs only access supervisor SPRs */ + if (vcpu->arch.papr_enabled && (level > PRIV_SUPER)) + return false; + + /* Limit user space to its own small SPR set */ + if ((vcpu->arch.shared->msr & MSR_PR) && level > PRIV_PROBLEM) + return false; + + return true; +} + int kvmppc_core_emulate_op(struct kvm_run *run, struct kvm_vcpu *vcpu, unsigned int inst, int *advance) { @@ -296,6 +315,8 @@ int kvmppc_core_emulate_mtspr(struct kvm_vcpu *vcpu, int sprn, int rs) switch (sprn) { case SPRN_SDR1: + if (!spr_allowed(vcpu, PRIV_HYPER)) + goto unprivileged; to_book3s(vcpu)->sdr1 = spr_val; break; case SPRN_DSISR: @@ -390,6 +411,7 @@ int kvmppc_core_emulate_mtspr(struct kvm_vcpu *vcpu, int sprn, int rs) case SPRN_PMC4_GEKKO: case SPRN_WPAR_GEKKO: break; +unprivileged: default: printk(KERN_INFO "KVM: invalid SPR write: %d\n", sprn); #ifndef DEBUG_SPR @@ -421,6 +443,8 @@ int kvmppc_core_emulate_mfspr(struct kvm_vcpu *vcpu, int sprn, int rt) break; } case SPRN_SDR1: + if (!spr_allowed(vcpu, PRIV_HYPER)) + goto unprivileged; kvmppc_set_gpr(vcpu, rt, to_book3s(vcpu)->sdr1); break; case SPRN_DSISR: @@ -476,6 +500,7 @@ int kvmppc_core_emulate_mfspr(struct kvm_vcpu *vcpu, int sprn, int rt) kvmppc_set_gpr(vcpu, rt, 0); break; default: +unprivileged: printk(KERN_INFO "KVM: invalid SPR read: %d\n", sprn); #ifndef DEBUG_SPR emulated = EMULATE_FAIL; |