Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
+29
-10
+10
arch/powerpc/kvm/book3s_64_mmu_hv.c
+10
arch/powerpc/kvm/book3s_64_mmu_hv.c
···
646
646
hnow_v = hpte_new_to_old_v(hnow_v, hnow_r);
647
647
hnow_r = hpte_new_to_old_r(hnow_r);
648
648
}
649
+
650
+
/*
651
+
* If the HPT is being resized, don't update the HPTE,
652
+
* instead let the guest retry after the resize operation is complete.
653
+
* The synchronization for hpte_setup_done test vs. set is provided
654
+
* by the HPTE lock.
655
+
*/
656
+
if (!kvm->arch.hpte_setup_done)
657
+
goto out_unlock;
658
+
649
659
if ((hnow_v & ~HPTE_V_HVLOCK) != hpte[0] || hnow_r != hpte[1] ||
650
660
rev->guest_rpte != hpte[2])
651
661
/* HPTE has been changed under us; let the guest retry */
+19
-10
arch/powerpc/kvm/book3s_hv.c
+19
-10
arch/powerpc/kvm/book3s_hv.c
···
2705
2705
* Hard-disable interrupts, and check resched flag and signals.
2706
2706
* If we need to reschedule or deliver a signal, clean up
2707
2707
* and return without going into the guest(s).
2708
+
* If the hpte_setup_done flag has been cleared, don't go into the
2709
+
* guest because that means a HPT resize operation is in progress.
2708
2710
*/
2709
2711
local_irq_disable();
2710
2712
hard_irq_disable();
2711
2713
if (lazy_irq_pending() || need_resched() ||
2712
-
recheck_signals(&core_info)) {
2714
+
recheck_signals(&core_info) ||
2715
+
(!kvm_is_radix(vc->kvm) && !vc->kvm->arch.hpte_setup_done)) {
2713
2716
local_irq_enable();
2714
2717
vc->vcore_state = VCORE_INACTIVE;
2715
2718
/* Unlock all except the primary vcore */
···
3081
3078
3082
3079
static int kvmppc_run_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
3083
3080
{
3084
-
int n_ceded, i;
3081
+
int n_ceded, i, r;
3085
3082
struct kvmppc_vcore *vc;
3086
3083
struct kvm_vcpu *v;
3087
3084
···
3135
3132
3136
3133
while (vcpu->arch.state == KVMPPC_VCPU_RUNNABLE &&
3137
3134
!signal_pending(current)) {
3135
+
/* See if the HPT and VRMA are ready to go */
3136
+
if (!kvm_is_radix(vcpu->kvm) &&
3137
+
!vcpu->kvm->arch.hpte_setup_done) {
3138
+
spin_unlock(&vc->lock);
3139
+
r = kvmppc_hv_setup_htab_rma(vcpu);
3140
+
spin_lock(&vc->lock);
3141
+
if (r) {
3142
+
kvm_run->exit_reason = KVM_EXIT_FAIL_ENTRY;
3143
+
kvm_run->fail_entry.hardware_entry_failure_reason = 0;
3144
+
vcpu->arch.ret = r;
3145
+
break;
3146
+
}
3147
+
}
3148
+
3138
3149
if (vc->vcore_state == VCORE_PREEMPT && vc->runner == NULL)
3139
3150
kvmppc_vcore_end_preempt(vc);
3140
3151
···
3266
3249
/* Order vcpus_running vs. hpte_setup_done, see kvmppc_alloc_reset_hpt */
3267
3250
smp_mb();
3268
3251
3269
-
/* On the first time here, set up HTAB and VRMA */
3270
-
if (!kvm_is_radix(vcpu->kvm) && !vcpu->kvm->arch.hpte_setup_done) {
3271
-
r = kvmppc_hv_setup_htab_rma(vcpu);
3272
-
if (r)
3273
-
goto out;
3274
-
}
3275
-
3276
3252
flush_all_to_thread(current);
3277
3253
3278
3254
/* Save userspace EBB and other register values */
···
3313
3303
}
3314
3304
mtspr(SPRN_VRSAVE, user_vrsave);
3315
3305
3316
-
out:
3317
3306
vcpu->arch.state = KVMPPC_VCPU_NOTREADY;
3318
3307
atomic_dec(&vcpu->kvm->arch.vcpus_running);
3319
3308
return r;