Merge branch 'kvm-ppc-next' of...

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

- Better machine check handling for HV KVM
- Ability to support guests with threads=2, 4 or 8 on POWER9
- Fix for a race that could cause delayed recognition of signals
- Fix for a bug where POWER9 guests could sleep with interrupts
  pending.

Documentation/virtual/kvm/api.txt

@@ -4131,6 +4131,34 @@ Parameters: none
 Allow use of adapter-interruption suppression.
 Returns: 0 on success; -EBUSY if a VCPU has already been created.
 
+7.11 KVM_CAP_PPC_SMT
+
+Architectures: ppc
+Parameters: vsmt_mode, flags
+
+Enabling this capability on a VM provides userspace with a way to set
+the desired virtual SMT mode (i.e. the number of virtual CPUs per
+virtual core).  The virtual SMT mode, vsmt_mode, must be a power of 2
+between 1 and 8.  On POWER8, vsmt_mode must also be no greater than
+the number of threads per subcore for the host.  Currently flags must
+be 0.  A successful call to enable this capability will result in
+vsmt_mode being returned when the KVM_CAP_PPC_SMT capability is
+subsequently queried for the VM.  This capability is only supported by
+HV KVM, and can only be set before any VCPUs have been created.
+The KVM_CAP_PPC_SMT_POSSIBLE capability indicates which virtual SMT
+modes are available.
+
+7.12 KVM_CAP_PPC_FWNMI
+
+Architectures: ppc
+Parameters: none
+
+With this capability a machine check exception in the guest address
+space will cause KVM to exit the guest with NMI exit reason. This
+enables QEMU to build error log and branch to guest kernel registered
+machine check handling routine. Without this capability KVM will
+branch to guests' 0x200 interrupt vector.
+
 8. Other capabilities.
 ----------------------
 
@@ -4292,3 +4320,12 @@ Currently the following bits are defined for the device_irq_level bitmap:
 Future versions of kvm may implement additional events. These will get
 indicated by returning a higher number from KVM_CHECK_EXTENSION and will be
 listed above.
+
+8.10 KVM_CAP_PPC_SMT_POSSIBLE
+
+Architectures: ppc
+
+Querying this capability returns a bitmap indicating the possible
+virtual SMT modes that can be set using KVM_CAP_PPC_SMT.  If bit N
+(counting from the right) is set, then a virtual SMT mode of 2^N is
+available.

arch/powerpc/include/asm/kvm_book3s.h

@@ -86,7 +86,6 @@ struct kvmppc_vcore {
 	u16 last_cpu;
 	u8 vcore_state;
 	u8 in_guest;
-	struct kvmppc_vcore *master_vcore;
 	struct kvm_vcpu *runnable_threads[MAX_SMT_THREADS];
 	struct list_head preempt_list;
 	spinlock_t lock;

arch/powerpc/include/asm/kvm_book3s_asm.h

@@ -81,7 +81,7 @@ struct kvm_split_mode {
 	u8		subcore_size;
 	u8		do_nap;
 	u8		napped[MAX_SMT_THREADS];
-	struct kvmppc_vcore *master_vcs[MAX_SUBCORES];
+	struct kvmppc_vcore *vc[MAX_SUBCORES];
 };
 
 /*

arch/powerpc/include/asm/kvm_host.h

@@ -35,6 +35,7 @@
 #include <asm/page.h>
 #include <asm/cacheflush.h>
 #include <asm/hvcall.h>
+#include <asm/mce.h>
 
 #define KVM_MAX_VCPUS		NR_CPUS
 #define KVM_MAX_VCORES		NR_CPUS
@@ -267,6 +268,8 @@ struct kvm_resize_hpt;
 
 struct kvm_arch {
 	unsigned int lpid;
+	unsigned int smt_mode;		/* # vcpus per virtual core */
+	unsigned int emul_smt_mode;	/* emualted SMT mode, on P9 */
 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
 	unsigned int tlb_sets;
 	struct kvm_hpt_info hpt;
@@ -285,6 +288,7 @@ struct kvm_arch {
 	cpumask_t need_tlb_flush;
 	cpumask_t cpu_in_guest;
 	u8 radix;
+	u8 fwnmi_enabled;
 	pgd_t *pgtable;
 	u64 process_table;
 	struct dentry *debugfs_dir;
@@ -566,6 +570,7 @@ struct kvm_vcpu_arch {
 	ulong wort;
 	ulong tid;
 	ulong psscr;
+	ulong hfscr;
 	ulong shadow_srr1;
 #endif
 	u32 vrsave; /* also USPRG0 */
@@ -579,7 +584,7 @@ struct kvm_vcpu_arch {
 	ulong mcsrr0;
 	ulong mcsrr1;
 	ulong mcsr;
-	u32 dec;
+	ulong dec;
 #ifdef CONFIG_BOOKE
 	u32 decar;
 #endif
@@ -710,6 +715,7 @@ struct kvm_vcpu_arch {
 	unsigned long pending_exceptions;
 	u8 ceded;
 	u8 prodded;
+	u8 doorbell_request;
 	u32 last_inst;
 
 	struct swait_queue_head *wqp;
@@ -722,6 +728,7 @@ struct kvm_vcpu_arch {
 	int prev_cpu;
 	bool timer_running;
 	wait_queue_head_t cpu_run;
+	struct machine_check_event mce_evt; /* Valid if trap == 0x200 */
 
 	struct kvm_vcpu_arch_shared *shared;
 #if defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_KVM_BOOK3S_PR_POSSIBLE)

arch/powerpc/include/asm/kvm_ppc.h

@@ -315,6 +315,8 @@ struct kvmppc_ops {
 					struct irq_bypass_producer *);
 	int (*configure_mmu)(struct kvm *kvm, struct kvm_ppc_mmuv3_cfg *cfg);
 	int (*get_rmmu_info)(struct kvm *kvm, struct kvm_ppc_rmmu_info *info);
+	int (*set_smt_mode)(struct kvm *kvm, unsigned long mode,
+			    unsigned long flags);
 };
 
 extern struct kvmppc_ops *kvmppc_hv_ops;

arch/powerpc/include/asm/ppc-opcode.h

@@ -103,6 +103,8 @@
 #define OP_31_XOP_STBUX     247
 #define OP_31_XOP_LHZX      279
 #define OP_31_XOP_LHZUX     311
+#define OP_31_XOP_MSGSNDP   142
+#define OP_31_XOP_MSGCLRP   174
 #define OP_31_XOP_MFSPR     339
 #define OP_31_XOP_LWAX      341
 #define OP_31_XOP_LHAX      343

arch/powerpc/include/uapi/asm/kvm.h

@@ -60,6 +60,12 @@ struct kvm_regs {
 
 #define KVM_SREGS_E_FSL_PIDn	(1 << 0) /* PID1/PID2 */
 
+/* flags for kvm_run.flags */
+#define KVM_RUN_PPC_NMI_DISP_MASK		(3 << 0)
+#define   KVM_RUN_PPC_NMI_DISP_FULLY_RECOV	(1 << 0)
+#define   KVM_RUN_PPC_NMI_DISP_LIMITED_RECOV	(2 << 0)
+#define   KVM_RUN_PPC_NMI_DISP_NOT_RECOV	(3 << 0)
+
 /*
  * Feature bits indicate which sections of the sregs struct are valid,
  * both in KVM_GET_SREGS and KVM_SET_SREGS.  On KVM_SET_SREGS, registers

arch/powerpc/kernel/asm-offsets.c

@@ -485,6 +485,7 @@ int main(void)
 	OFFSET(KVM_ENABLED_HCALLS, kvm, arch.enabled_hcalls);
 	OFFSET(KVM_VRMA_SLB_V, kvm, arch.vrma_slb_v);
 	OFFSET(KVM_RADIX, kvm, arch.radix);
+	OFFSET(KVM_FWNMI, kvm, arch.fwnmi_enabled);
 	OFFSET(VCPU_DSISR, kvm_vcpu, arch.shregs.dsisr);
 	OFFSET(VCPU_DAR, kvm_vcpu, arch.shregs.dar);
 	OFFSET(VCPU_VPA, kvm_vcpu, arch.vpa.pinned_addr);
@@ -513,6 +514,7 @@ int main(void)
 	OFFSET(VCPU_PENDING_EXC, kvm_vcpu, arch.pending_exceptions);
 	OFFSET(VCPU_CEDED, kvm_vcpu, arch.ceded);
 	OFFSET(VCPU_PRODDED, kvm_vcpu, arch.prodded);
+	OFFSET(VCPU_DBELL_REQ, kvm_vcpu, arch.doorbell_request);
 	OFFSET(VCPU_MMCR, kvm_vcpu, arch.mmcr);
 	OFFSET(VCPU_PMC, kvm_vcpu, arch.pmc);
 	OFFSET(VCPU_SPMC, kvm_vcpu, arch.spmc);
@@ -542,6 +544,7 @@ int main(void)
 	OFFSET(VCPU_WORT, kvm_vcpu, arch.wort);
 	OFFSET(VCPU_TID, kvm_vcpu, arch.tid);
 	OFFSET(VCPU_PSSCR, kvm_vcpu, arch.psscr);
+	OFFSET(VCPU_HFSCR, kvm_vcpu, arch.hfscr);
 	OFFSET(VCORE_ENTRY_EXIT, kvmppc_vcore, entry_exit_map);
 	OFFSET(VCORE_IN_GUEST, kvmppc_vcore, in_guest);
 	OFFSET(VCORE_NAPPING_THREADS, kvmppc_vcore, napping_threads);

arch/powerpc/kernel/mce.c

@@ -405,6 +405,7 @@ void machine_check_print_event_info(struct machine_check_event *evt,
 		break;
 	}
 }
+EXPORT_SYMBOL_GPL(machine_check_print_event_info);
 
 uint64_t get_mce_fault_addr(struct machine_check_event *evt)
 {

arch/powerpc/kvm/book3s_hv_builtin.c

@@ -307,7 +307,7 @@ void kvmhv_commence_exit(int trap)
 		return;
 
 	for (i = 0; i < MAX_SUBCORES; ++i) {
-		vc = sip->master_vcs[i];
+		vc = sip->vc[i];
 		if (!vc)
 			break;
 		do {

arch/powerpc/kvm/book3s_hv_interrupts.S

@@ -61,13 +61,6 @@ BEGIN_FTR_SECTION
 	std	r3, HSTATE_DABR(r13)
 END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 
-	/* Hard-disable interrupts */
-	mfmsr   r10
-	std	r10, HSTATE_HOST_MSR(r13)
-	rldicl  r10,r10,48,1
-	rotldi  r10,r10,16
-	mtmsrd  r10,1
-
 	/* Save host PMU registers */
 BEGIN_FTR_SECTION
 	/* Work around P8 PMAE bug */
@@ -121,10 +114,20 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	 * Put whatever is in the decrementer into the
 	 * hypervisor decrementer.
 	 */
+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)
 	mfspr	r8,SPRN_DEC
 	mftb	r7
-	mtspr	SPRN_HDEC,r8
+BEGIN_FTR_SECTION
+	/* On POWER9, don't sign-extend if host LPCR[LD] bit is set */
+	bne	32f
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	extsw	r8,r8
+32:	mtspr	SPRN_HDEC,r8
 	add	r8,r8,r7
 	std	r8,HSTATE_DECEXP(r13)
 
@@ -143,6 +146,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	 *
 	 * R1       = host R1
 	 * R2       = host R2
+	 * R3       = trap number on this thread
 	 * R12      = exit handler id
 	 * R13      = PACA
 	 */

arch/powerpc/kvm/book3s_hv_ras.c

@@ -130,12 +130,28 @@ static long kvmppc_realmode_mc_power7(struct kvm_vcpu *vcpu)
 
 out:
 	/*
+	 * For guest that supports FWNMI capability, hook the MCE event into
+	 * vcpu structure. We are going to exit the guest with KVM_EXIT_NMI
+	 * exit reason. On our way to exit we will pull this event from vcpu
+	 * structure and print it from thread 0 of the core/subcore.
+	 *
+	 * For guest that does not support FWNMI capability (old QEMU):
 	 * We are now going enter guest either through machine check
 	 * interrupt (for unhandled errors) or will continue from
 	 * current HSRR0 (for handled errors) in guest. Hence
 	 * queue up the event so that we can log it from host console later.
 	 */
-	machine_check_queue_event();
+	if (vcpu->kvm->arch.fwnmi_enabled) {
+		/*
+		 * Hook up the mce event on to vcpu structure.
+		 * First clear the old event.
+		 */
+		memset(&vcpu->arch.mce_evt, 0, sizeof(vcpu->arch.mce_evt));
+		if (get_mce_event(&mce_evt, MCE_EVENT_RELEASE)) {
+			vcpu->arch.mce_evt = mce_evt;
+		}
+	} else
+		machine_check_queue_event();
 
 	return handled;
 }

arch/powerpc/kvm/emulate.c

@@ -39,7 +39,7 @@ void kvmppc_emulate_dec(struct kvm_vcpu *vcpu)
 	unsigned long dec_nsec;
 	unsigned long long dec_time;
 
-	pr_debug("mtDEC: %x\n", vcpu->arch.dec);
+	pr_debug("mtDEC: %lx\n", vcpu->arch.dec);
 	hrtimer_try_to_cancel(&vcpu->arch.dec_timer);
 
 #ifdef CONFIG_PPC_BOOK3S
@@ -109,7 +109,7 @@ static int kvmppc_emulate_mtspr(struct kvm_vcpu *vcpu, int sprn, int rs)
 	case SPRN_TBWU: break;
 
 	case SPRN_DEC:
-		vcpu->arch.dec = spr_val;
+		vcpu->arch.dec = (u32) spr_val;
 		kvmppc_emulate_dec(vcpu);
 		break;
 

arch/powerpc/kvm/powerpc.c

@@ -553,13 +553,28 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
 	case KVM_CAP_PPC_SMT:
 		r = 0;
-		if (hv_enabled) {
+		if (kvm) {
+			if (kvm->arch.emul_smt_mode > 1)
+				r = kvm->arch.emul_smt_mode;
+			else
+				r = kvm->arch.smt_mode;
+		} else if (hv_enabled) {
 			if (cpu_has_feature(CPU_FTR_ARCH_300))
 				r = 1;
 			else
 				r = threads_per_subcore;
 		}
 		break;
+	case KVM_CAP_PPC_SMT_POSSIBLE:
+		r = 1;
+		if (hv_enabled) {
+			if (!cpu_has_feature(CPU_FTR_ARCH_300))
+				r = ((threads_per_subcore << 1) - 1);
+			else
+				/* P9 can emulate dbells, so allow any mode */
+				r = 8 | 4 | 2 | 1;
+		}
+		break;
 	case KVM_CAP_PPC_RMA:
 		r = 0;
 		break;
@@ -617,6 +632,11 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 		/* Disable this on POWER9 until code handles new HPTE format */
 		r = !!hv_enabled && !cpu_has_feature(CPU_FTR_ARCH_300);
 		break;
+#endif
+#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+	case KVM_CAP_PPC_FWNMI:
+		r = hv_enabled;
+		break;
 #endif
 	case KVM_CAP_PPC_HTM:
 		r = cpu_has_feature(CPU_FTR_TM_COMP) &&
@@ -1537,6 +1557,15 @@ static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
 		break;
 	}
 #endif /* CONFIG_KVM_XICS */
+#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+	case KVM_CAP_PPC_FWNMI:
+		r = -EINVAL;
+		if (!is_kvmppc_hv_enabled(vcpu->kvm))
+			break;
+		r = 0;
+		vcpu->kvm->arch.fwnmi_enabled = true;
+		break;
+#endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
 	default:
 		r = -EINVAL;
 		break;
@@ -1711,6 +1740,15 @@ static int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
 		r = 0;
 		break;
 	}
+	case KVM_CAP_PPC_SMT: {
+		unsigned long mode = cap->args[0];
+		unsigned long flags = cap->args[1];
+
+		r = -EINVAL;
+		if (kvm->arch.kvm_ops->set_smt_mode)
+			r = kvm->arch.kvm_ops->set_smt_mode(kvm, mode, flags);
+		break;
+	}
 #endif
 	default:
 		r = -EINVAL;

include/uapi/linux/kvm.h

@@ -925,6 +925,8 @@ struct kvm_ppc_resize_hpt {
 #define KVM_CAP_X86_GUEST_MWAIT 143
 #define KVM_CAP_ARM_USER_IRQ 144
 #define KVM_CAP_S390_CMMA_MIGRATION 145
+#define KVM_CAP_PPC_FWNMI 146
+#define KVM_CAP_PPC_SMT_POSSIBLE 147
 
 #ifdef KVM_CAP_IRQ_ROUTING