Merge tag 'kvm-ppc-next-5.10-1' of...

Merge tag 'kvm-ppc-next-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD

PPC KVM update for 5.10

- Fix for running nested guests with in-kernel IRQ chip
- Fix race condition causing occasional host hard lockup
- Minor cleanups and bugfixes

arch/powerpc/include/asm/kvm_host.h

@@ -326,6 +326,7 @@ struct kvm_arch {
 #endif
 #ifdef CONFIG_KVM_XICS
 	struct kvmppc_xics *xics;
+	struct kvmppc_xics *xics_device;
 	struct kvmppc_xive *xive;    /* Current XIVE device in use */
 	struct {
 		struct kvmppc_xive *native;

arch/powerpc/kvm/book3s.c

@@ -558,12 +558,12 @@ int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 
 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 {
-	return -ENOTSUPP;
+	return -EOPNOTSUPP;
 }
 
 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 {
-	return -ENOTSUPP;
+	return -EOPNOTSUPP;
 }
 
 int kvmppc_get_one_reg(struct kvm_vcpu *vcpu, u64 id,
@@ -879,13 +879,15 @@ void kvmppc_core_destroy_vm(struct kvm *kvm)
 
 #ifdef CONFIG_KVM_XICS
 	/*
-	 * Free the XIVE devices which are not directly freed by the
+	 * Free the XIVE and XICS devices which are not directly freed by the
 	 * device 'release' method
 	 */
 	kfree(kvm->arch.xive_devices.native);
 	kvm->arch.xive_devices.native = NULL;
 	kfree(kvm->arch.xive_devices.xics_on_xive);
 	kvm->arch.xive_devices.xics_on_xive = NULL;
+	kfree(kvm->arch.xics_device);
+	kvm->arch.xics_device = NULL;
 #endif /* CONFIG_KVM_XICS */
 }
 

arch/powerpc/kvm/book3s_64_mmu_radix.c

@@ -347,7 +347,7 @@ static unsigned long kvmppc_radix_update_pte(struct kvm *kvm, pte_t *ptep,
 	return __radix_pte_update(ptep, clr, set);
 }
 
-void kvmppc_radix_set_pte_at(struct kvm *kvm, unsigned long addr,
+static void kvmppc_radix_set_pte_at(struct kvm *kvm, unsigned long addr,
 			     pte_t *ptep, pte_t pte)
 {
 	radix__set_pte_at(kvm->mm, addr, ptep, pte, 0);

arch/powerpc/kvm/book3s_64_vio.c

@@ -283,7 +283,7 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
 	struct kvmppc_spapr_tce_table *siter;
 	struct mm_struct *mm = kvm->mm;
 	unsigned long npages, size = args->size;
-	int ret = -ENOMEM;
+	int ret;
 
 	if (!args->size || args->page_shift < 12 || args->page_shift > 34 ||
 		(args->offset + args->size > (ULLONG_MAX >> args->page_shift)))
@@ -489,7 +489,7 @@ static long kvmppc_tce_iommu_unmap(struct kvm *kvm,
 	return ret;
 }
 
-long kvmppc_tce_iommu_do_map(struct kvm *kvm, struct iommu_table *tbl,
+static long kvmppc_tce_iommu_do_map(struct kvm *kvm, struct iommu_table *tbl,
 		unsigned long entry, unsigned long ua,
 		enum dma_data_direction dir)
 {

arch/powerpc/kvm/book3s_64_vio_hv.c

@@ -237,7 +237,7 @@ static long iommu_tce_xchg_no_kill_rm(struct mm_struct *mm,
 	return ret;
 }
 
-extern void iommu_tce_kill_rm(struct iommu_table *tbl,
+static void iommu_tce_kill_rm(struct iommu_table *tbl,
 		unsigned long entry, unsigned long pages)
 {
 	if (tbl->it_ops->tce_kill)

arch/powerpc/kvm/book3s_hv.c

@@ -3442,9 +3442,19 @@ static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu *vcpu, u64 time_limit,
 	unsigned long host_psscr = mfspr(SPRN_PSSCR);
 	unsigned long host_pidr = mfspr(SPRN_PID);
 
+	/*
+	 * P8 and P9 suppress the HDEC exception when LPCR[HDICE] = 0,
+	 * so set HDICE before writing HDEC.
+	 */
+	mtspr(SPRN_LPCR, vcpu->kvm->arch.host_lpcr | LPCR_HDICE);
+	isync();
+
 	hdec = time_limit - mftb();
-	if (hdec < 0)
+	if (hdec < 0) {
+		mtspr(SPRN_LPCR, vcpu->kvm->arch.host_lpcr);
+		isync();
 		return BOOK3S_INTERRUPT_HV_DECREMENTER;
+	}
 	mtspr(SPRN_HDEC, hdec);
 
 	if (vc->tb_offset) {
@@ -3558,7 +3568,7 @@ static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu *vcpu, u64 time_limit,
  * Virtual-mode guest entry for POWER9 and later when the host and
  * guest are both using the radix MMU.  The LPIDR has already been set.
  */
-int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
+static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 			 unsigned long lpcr)
 {
 	struct kvmppc_vcore *vc = vcpu->arch.vcore;
@@ -3572,7 +3582,7 @@ int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 
 	dec = mfspr(SPRN_DEC);
 	tb = mftb();
-	if (dec < 512)
+	if (dec < 0)
 		return BOOK3S_INTERRUPT_HV_DECREMENTER;
 	local_paca->kvm_hstate.dec_expires = dec + tb;
 	if (local_paca->kvm_hstate.dec_expires < time_limit)
@@ -5250,6 +5260,12 @@ static long kvm_arch_vm_ioctl_hv(struct file *filp,
 	case KVM_PPC_ALLOCATE_HTAB: {
 		u32 htab_order;
 
+		/* If we're a nested hypervisor, we currently only support radix */
+		if (kvmhv_on_pseries()) {
+			r = -EOPNOTSUPP;
+			break;
+		}
+
 		r = -EFAULT;
 		if (get_user(htab_order, (u32 __user *)argp))
 			break;

arch/powerpc/kvm/book3s_hv_interrupts.S

@@ -58,13 +58,16 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 	/*
 	 * Put whatever is in the decrementer into the
 	 * hypervisor decrementer.
+	 * Because of a hardware deviation in P8 and P9,
+	 * we need to set LPCR[HDICE] before writing HDEC.
 	 */
-BEGIN_FTR_SECTION
 	ld	r5, HSTATE_KVM_VCORE(r13)
 	ld	r6, VCORE_KVM(r5)
 	ld	r9, KVM_HOST_LPCR(r6)
-	andis.	r9, r9, LPCR_LD@h
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
+	ori	r8, r9, LPCR_HDICE
+	mtspr	SPRN_LPCR, r8
+	isync
+	andis.	r0, r9, LPCR_LD@h
 	mfspr	r8,SPRN_DEC
 	mftb	r7
 BEGIN_FTR_SECTION

arch/powerpc/kvm/book3s_hv_nested.c

@@ -569,7 +569,7 @@ static void kvmhv_update_ptbl_cache(struct kvm_nested_guest *gp)
 	kvmhv_set_nested_ptbl(gp);
 }
 
-struct kvm_nested_guest *kvmhv_alloc_nested(struct kvm *kvm, unsigned int lpid)
+static struct kvm_nested_guest *kvmhv_alloc_nested(struct kvm *kvm, unsigned int lpid)
 {
 	struct kvm_nested_guest *gp;
 	long shadow_lpid;

arch/powerpc/kvm/book3s_hv_rm_xics.c

@@ -764,7 +764,7 @@ int xics_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr)
 	return ics_rm_eoi(vcpu, irq);
 }
 
-unsigned long eoi_rc;
+static unsigned long eoi_rc;
 
 static void icp_eoi(struct irq_chip *c, u32 hwirq, __be32 xirr, bool *again)
 {

arch/powerpc/kvm/book3s_pr.c

@@ -569,7 +569,7 @@ static void kvmppc_set_msr_pr(struct kvm_vcpu *vcpu, u64 msr)
 #endif
 }
 
-void kvmppc_set_pvr_pr(struct kvm_vcpu *vcpu, u32 pvr)
+static void kvmppc_set_pvr_pr(struct kvm_vcpu *vcpu, u32 pvr)
 {
 	u32 host_pvr;
 

arch/powerpc/kvm/book3s_xics.c

@@ -1334,47 +1334,97 @@ static int xics_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
 	return -ENXIO;
 }
 
-static void kvmppc_xics_free(struct kvm_device *dev)
+/*
+ * Called when device fd is closed. kvm->lock is held.
+ */
+static void kvmppc_xics_release(struct kvm_device *dev)
 {
 	struct kvmppc_xics *xics = dev->private;
 	int i;
 	struct kvm *kvm = xics->kvm;
+	struct kvm_vcpu *vcpu;
+
+	pr_devel("Releasing xics device\n");
+
+	/*
+	 * 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
+	 * attribute set/get functions being executed concurrently,
+	 * and similarly, the connect_vcpu and set/clr_mapped
+	 * functions also cannot be being executed.
+	 */
 
 	debugfs_remove(xics->dentry);
 
+	/*
+	 * We should clean up the vCPU interrupt presenters first.
+	 */
+	kvm_for_each_vcpu(i, vcpu, kvm) {
+		/*
+		 * Take vcpu->mutex to ensure that no one_reg get/set ioctl
+		 * (i.e. kvmppc_xics_[gs]et_icp) can be done concurrently.
+		 * Holding the vcpu->mutex also means that execution is
+		 * excluded for the vcpu until the ICP was freed. When the vcpu
+		 * can execute again, vcpu->arch.icp and vcpu->arch.irq_type
+		 * have been cleared and the vcpu will not be going into the
+		 * XICS code anymore.
+		 */
+		mutex_lock(&vcpu->mutex);
+		kvmppc_xics_free_icp(vcpu);
+		mutex_unlock(&vcpu->mutex);
+	}
+
 	if (kvm)
 		kvm->arch.xics = NULL;
 
-	for (i = 0; i <= xics->max_icsid; i++)
+	for (i = 0; i <= xics->max_icsid; i++) {
 		kfree(xics->ics[i]);
-	kfree(xics);
+		xics->ics[i] = NULL;
+	}
+	/*
+	 * A reference of the kvmppc_xics pointer is now kept under
+	 * the xics_device pointer of the machine for reuse. It is
+	 * freed when the VM is destroyed for now until we fix all the
+	 * execution paths.
+	 */
 	kfree(dev);
 }
 
+static struct kvmppc_xics *kvmppc_xics_get_device(struct kvm *kvm)
+{
+	struct kvmppc_xics **kvm_xics_device = &kvm->arch.xics_device;
+	struct kvmppc_xics *xics = *kvm_xics_device;
+
+	if (!xics) {
+		xics = kzalloc(sizeof(*xics), GFP_KERNEL);
+		*kvm_xics_device = xics;
+	} else {
+		memset(xics, 0, sizeof(*xics));
+	}
+
+	return xics;
+}
+
 static int kvmppc_xics_create(struct kvm_device *dev, u32 type)
 {
 	struct kvmppc_xics *xics;
 	struct kvm *kvm = dev->kvm;
-	int ret = 0;
 
-	xics = kzalloc(sizeof(*xics), GFP_KERNEL);
+	pr_devel("Creating xics for partition\n");
+
+	/* Already there ? */
+	if (kvm->arch.xics)
+		return -EEXIST;
+
+	xics = kvmppc_xics_get_device(kvm);
 	if (!xics)
 		return -ENOMEM;
 
 	dev->private = xics;
 	xics->dev = dev;
 	xics->kvm = kvm;
-
-	/* Already there ? */
-	if (kvm->arch.xics)
-		ret = -EEXIST;
-	else
-		kvm->arch.xics = xics;
-
-	if (ret) {
-		kfree(xics);
-		return ret;
-	}
+	kvm->arch.xics = xics;
 
 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
 	if (cpu_has_feature(CPU_FTR_ARCH_206) &&
@@ -1399,7 +1449,7 @@ struct kvm_device_ops kvm_xics_ops = {
 	.name = "kvm-xics",
 	.create = kvmppc_xics_create,
 	.init = kvmppc_xics_init,
-	.destroy = kvmppc_xics_free,
+	.release = kvmppc_xics_release,
 	.set_attr = xics_set_attr,
 	.get_attr = xics_get_attr,
 	.has_attr = xics_has_attr,
@@ -1415,7 +1465,7 @@ int kvmppc_xics_connect_vcpu(struct kvm_device *dev, struct kvm_vcpu *vcpu,
 		return -EPERM;
 	if (xics->kvm != vcpu->kvm)
 		return -EPERM;
-	if (vcpu->arch.irq_type)
+	if (vcpu->arch.irq_type != KVMPPC_IRQ_DEFAULT)
 		return -EBUSY;
 
 	r = kvmppc_xics_create_icp(vcpu, xcpu);

arch/powerpc/kvm/book3s_xive_native.c

@@ -1227,17 +1227,7 @@ static int xive_native_debug_show(struct seq_file *m, void *private)
 	return 0;
 }
 
-static int xive_native_debug_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, xive_native_debug_show, inode->i_private);
-}
-
-static const struct file_operations xive_native_debug_fops = {
-	.open = xive_native_debug_open,
-	.read = seq_read,
-	.llseek = seq_lseek,
-	.release = single_release,
-};
+DEFINE_SHOW_ATTRIBUTE(xive_native_debug);
 
 static void xive_native_debugfs_init(struct kvmppc_xive *xive)
 {

arch/powerpc/kvm/booke.c

@@ -1747,12 +1747,12 @@ int kvmppc_set_one_reg(struct kvm_vcpu *vcpu, u64 id,
 
 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 {
-	return -ENOTSUPP;
+	return -EOPNOTSUPP;
 }
 
 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 {
-	return -ENOTSUPP;
+	return -EOPNOTSUPP;
 }
 
 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
@@ -1773,7 +1773,7 @@ void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
 
 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
 {
-	return -ENOTSUPP;
+	return -EOPNOTSUPP;
 }
 
 void kvmppc_core_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot)