diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_xive.c')
| -rw-r--r-- | arch/powerpc/kvm/book3s_xive.c | 28 |
1 files changed, 12 insertions, 16 deletions
diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c index 4953957333b7..f623451ec0a3 100644 --- a/arch/powerpc/kvm/book3s_xive.c +++ b/arch/powerpc/kvm/book3s_xive.c @@ -1859,21 +1859,10 @@ static void kvmppc_xive_release(struct kvm_device *dev) struct kvm *kvm = xive->kvm; struct kvm_vcpu *vcpu; int i; - int was_ready; pr_devel("Releasing xive device\n"); - debugfs_remove(xive->dentry); - /* - * Clearing mmu_ready temporarily while holding kvm->lock - * is a way of ensuring that no vcpus can enter the guest - * until we drop kvm->lock. Doing kick_all_cpus_sync() - * ensures that any vcpu executing inside the guest has - * exited the guest. Once kick_all_cpus_sync() has finished, - * we know that no vcpu can be executing the XIVE push or - * pull code, or executing a XICS hcall. - * * Since this is the device release function, we know that * userspace does not have any open fd referring to the * device. Therefore there can not be any of the device @@ -1881,9 +1870,8 @@ static void kvmppc_xive_release(struct kvm_device *dev) * and similarly, the connect_vcpu and set/clr_mapped * functions also cannot be being executed. */ - was_ready = kvm->arch.mmu_ready; - kvm->arch.mmu_ready = 0; - kick_all_cpus_sync(); + + debugfs_remove(xive->dentry); /* * We should clean up the vCPU interrupt presenters first. @@ -1892,12 +1880,22 @@ static void kvmppc_xive_release(struct kvm_device *dev) /* * Take vcpu->mutex to ensure that no one_reg get/set ioctl * (i.e. kvmppc_xive_[gs]et_icp) can be done concurrently. + * Holding the vcpu->mutex also means that the vcpu cannot + * be executing the KVM_RUN ioctl, and therefore it cannot + * be executing the XIVE push or pull code or accessing + * the XIVE MMIO regions. */ mutex_lock(&vcpu->mutex); kvmppc_xive_cleanup_vcpu(vcpu); mutex_unlock(&vcpu->mutex); } + /* + * Now that we have cleared vcpu->arch.xive_vcpu, vcpu->arch.irq_type + * and vcpu->arch.xive_esc_[vr]addr on each vcpu, we are safe + * against xive code getting called during vcpu execution or + * set/get one_reg operations. + */ kvm->arch.xive = NULL; /* Mask and free interrupts */ @@ -1911,8 +1909,6 @@ static void kvmppc_xive_release(struct kvm_device *dev) if (xive->vp_base != XIVE_INVALID_VP) xive_native_free_vp_block(xive->vp_base); - kvm->arch.mmu_ready = was_ready; - /* * A reference of the kvmppc_xive pointer is now kept under * the xive_devices struct of the machine for reuse. It is |