diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-11-10 12:24:42 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-11-10 12:24:42 -0800 |
commit | 5cf2360ba6eceee13ac2e72f4c21fdd31613f59b (patch) | |
tree | 751abdc68ebb4fa9a26201df26a20fb040fa60d1 | |
parent | a579e949378eab7b992d2bf942b655ca407f2948 (diff) | |
parent | d850a255d5b961fbe085f06ddd116910378b78f1 (diff) | |
download | linux-stable-5cf2360ba6eceee13ac2e72f4c21fdd31613f59b.tar.gz linux-stable-5cf2360ba6eceee13ac2e72f4c21fdd31613f59b.tar.bz2 linux-stable-5cf2360ba6eceee13ac2e72f4c21fdd31613f59b.zip |
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fix from Radim Krčmář:
"Fix PPC HV host crash that can occur as a result of resizing the guest
hashed page table"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: PPC: Book3S HV: Fix exclusion between HPT resizing and other HPT updates
-rw-r--r-- | arch/powerpc/kvm/book3s_64_mmu_hv.c | 10 | ||||
-rw-r--r-- | arch/powerpc/kvm/book3s_hv.c | 29 |
2 files changed, 29 insertions, 10 deletions
diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index 7c62967d672c..59247af5fd45 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -646,6 +646,16 @@ int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu, hnow_v = hpte_new_to_old_v(hnow_v, hnow_r); hnow_r = hpte_new_to_old_r(hnow_r); } + + /* + * If the HPT is being resized, don't update the HPTE, + * instead let the guest retry after the resize operation is complete. + * The synchronization for hpte_setup_done test vs. set is provided + * by the HPTE lock. + */ + if (!kvm->arch.hpte_setup_done) + goto out_unlock; + if ((hnow_v & ~HPTE_V_HVLOCK) != hpte[0] || hnow_r != hpte[1] || rev->guest_rpte != hpte[2]) /* HPTE has been changed under us; let the guest retry */ diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 73bf1ebfa78f..8d43cf205d34 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -2705,11 +2705,14 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) * Hard-disable interrupts, and check resched flag and signals. * If we need to reschedule or deliver a signal, clean up * and return without going into the guest(s). + * If the hpte_setup_done flag has been cleared, don't go into the + * guest because that means a HPT resize operation is in progress. */ local_irq_disable(); hard_irq_disable(); if (lazy_irq_pending() || need_resched() || - recheck_signals(&core_info)) { + recheck_signals(&core_info) || + (!kvm_is_radix(vc->kvm) && !vc->kvm->arch.hpte_setup_done)) { local_irq_enable(); vc->vcore_state = VCORE_INACTIVE; /* Unlock all except the primary vcore */ @@ -3078,7 +3081,7 @@ out: static int kvmppc_run_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) { - int n_ceded, i; + int n_ceded, i, r; struct kvmppc_vcore *vc; struct kvm_vcpu *v; @@ -3132,6 +3135,20 @@ static int kvmppc_run_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) while (vcpu->arch.state == KVMPPC_VCPU_RUNNABLE && !signal_pending(current)) { + /* See if the HPT and VRMA are ready to go */ + if (!kvm_is_radix(vcpu->kvm) && + !vcpu->kvm->arch.hpte_setup_done) { + spin_unlock(&vc->lock); + r = kvmppc_hv_setup_htab_rma(vcpu); + spin_lock(&vc->lock); + if (r) { + kvm_run->exit_reason = KVM_EXIT_FAIL_ENTRY; + kvm_run->fail_entry.hardware_entry_failure_reason = 0; + vcpu->arch.ret = r; + break; + } + } + if (vc->vcore_state == VCORE_PREEMPT && vc->runner == NULL) kvmppc_vcore_end_preempt(vc); @@ -3249,13 +3266,6 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu) /* Order vcpus_running vs. hpte_setup_done, see kvmppc_alloc_reset_hpt */ smp_mb(); - /* On the first time here, set up HTAB and VRMA */ - if (!kvm_is_radix(vcpu->kvm) && !vcpu->kvm->arch.hpte_setup_done) { - r = kvmppc_hv_setup_htab_rma(vcpu); - if (r) - goto out; - } - flush_all_to_thread(current); /* Save userspace EBB and other register values */ @@ -3303,7 +3313,6 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu) } mtspr(SPRN_VRSAVE, user_vrsave); - out: vcpu->arch.state = KVMPPC_VCPU_NOTREADY; atomic_dec(&vcpu->kvm->arch.vcpus_running); return r; |