Merge tag 'powerpc-4.3-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:

- Revert "Use the POWER8 Micro Partition Prefetch Engine in KVM HV on
POWER8" from Paul
- Handle irq_happened flag correctly in off-line loop from Paul
- Validate rtas.entry before calling enter_rtas() from Vasant

* tag 'powerpc-4.3-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/rtas: Validate rtas.entry before calling enter_rtas()
powerpc/powernv: Handle irq_happened flag correctly in off-line loop
powerpc: Revert "Use the POWER8 Micro Partition Prefetch Engine in KVM HV on POWER8"

arch/powerpc/include/asm/cache.h

···
 
 #ifdef __KERNEL__
 
-#include <asm/reg.h>
 
 /* bytes per L1 cache line */
 #if defined(CONFIG_8xx) || defined(CONFIG_403GCX)
···
 };
 
 extern struct ppc64_caches ppc64_caches;
-
-static inline void logmpp(u64 x)
-{
-	asm volatile(PPC_LOGMPP(R1) : : "r" (x));
-}
-
 #endif /* __powerpc64__ && ! __ASSEMBLY__ */
 
 #if defined(__ASSEMBLY__)

arch/powerpc/include/asm/kvm_host.h

···
 	u32 arch_compat;
 	ulong pcr;
 	ulong dpdes;		/* doorbell state (POWER8) */
-	void *mpp_buffer; /* Micro Partition Prefetch buffer */
-	bool mpp_buffer_is_valid;
 	ulong conferring_threads;
 };
 

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

···
 #define PPC_INST_ISEL			0x7c00001e
 #define PPC_INST_ISEL_MASK		0xfc00003e
 #define PPC_INST_LDARX			0x7c0000a8
-#define PPC_INST_LOGMPP			0x7c0007e4
 #define PPC_INST_LSWI			0x7c0004aa
 #define PPC_INST_LSWX			0x7c00042a
 #define PPC_INST_LWARX			0x7c000028
···
 #define __PPC_EH(eh)	0
 #endif
 
-/* POWER8 Micro Partition Prefetch (MPP) parameters */
-/* Address mask is common for LOGMPP instruction and MPPR SPR */
-#define PPC_MPPE_ADDRESS_MASK 0xffffffffc000ULL
-
-/* Bits 60 and 61 of MPP SPR should be set to one of the following */
-/* Aborting the fetch is indeed setting 00 in the table size bits */
-#define PPC_MPPR_FETCH_ABORT (0x0ULL << 60)
-#define PPC_MPPR_FETCH_WHOLE_TABLE (0x2ULL << 60)
-
-/* Bits 54 and 55 of register for LOGMPP instruction should be set to: */
-#define PPC_LOGMPP_LOG_L2 (0x02ULL << 54)
-#define PPC_LOGMPP_LOG_L2L3 (0x01ULL << 54)
-#define PPC_LOGMPP_LOG_ABORT (0x03ULL << 54)
-
 /* Deal with instructions that older assemblers aren't aware of */
 #define	PPC_DCBAL(a, b)		stringify_in_c(.long PPC_INST_DCBAL | \
 					__PPC_RA(a) | __PPC_RB(b))
···
 #define PPC_LDARX(t, a, b, eh)	stringify_in_c(.long PPC_INST_LDARX | \
 					___PPC_RT(t) | ___PPC_RA(a) | \
 					___PPC_RB(b) | __PPC_EH(eh))
-#define PPC_LOGMPP(b)		stringify_in_c(.long PPC_INST_LOGMPP | \
-					__PPC_RB(b))
 #define PPC_LWARX(t, a, b, eh)	stringify_in_c(.long PPC_INST_LWARX | \
 					___PPC_RT(t) | ___PPC_RA(a) | \
 					___PPC_RB(b) | __PPC_EH(eh))

arch/powerpc/include/asm/reg.h

···
 #define   CTRL_TE	0x00c00000	/* thread enable */
 #define   CTRL_RUNLATCH	0x1
 #define SPRN_DAWR	0xB4
-#define SPRN_MPPR	0xB8	/* Micro Partition Prefetch Register */
 #define SPRN_RPR	0xBA	/* Relative Priority Register */
 #define SPRN_CIABR	0xBB
 #define   CIABR_PRIV		0x3

arch/powerpc/kernel/rtas.c

···
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
 
+	if (!rtas.entry)
+		return -EINVAL;
+
 	if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0)
 		return -EFAULT;
 

arch/powerpc/kvm/book3s_hv.c

···
 
 #include <asm/reg.h>
 #include <asm/cputable.h>
-#include <asm/cache.h>
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
 #include <asm/uaccess.h>
···
 #define TB_NIL	(~(u64)0)
 
 static DECLARE_BITMAP(default_enabled_hcalls, MAX_HCALL_OPCODE/4 + 1);
-
-#if defined(CONFIG_PPC_64K_PAGES)
-#define MPP_BUFFER_ORDER	0
-#elif defined(CONFIG_PPC_4K_PAGES)
-#define MPP_BUFFER_ORDER	3
-#endif
 
 static int dynamic_mt_modes = 6;
 module_param(dynamic_mt_modes, int, S_IRUGO | S_IWUSR);
···
 	vcore->kvm = kvm;
 	INIT_LIST_HEAD(&vcore->preempt_list);
 
-	vcore->mpp_buffer_is_valid = false;
-
-	if (cpu_has_feature(CPU_FTR_ARCH_207S))
-		vcore->mpp_buffer = (void *)__get_free_pages(
-			GFP_KERNEL|__GFP_ZERO,
-			MPP_BUFFER_ORDER);
-
 	return vcore;
 }
 
···
 		}
 	}
 	return 1;
-}
-
-static void kvmppc_start_saving_l2_cache(struct kvmppc_vcore *vc)
-{
-	phys_addr_t phy_addr, mpp_addr;
-
-	phy_addr = (phys_addr_t)virt_to_phys(vc->mpp_buffer);
-	mpp_addr = phy_addr & PPC_MPPE_ADDRESS_MASK;
-
-	mtspr(SPRN_MPPR, mpp_addr | PPC_MPPR_FETCH_ABORT);
-	logmpp(mpp_addr | PPC_LOGMPP_LOG_L2);
-
-	vc->mpp_buffer_is_valid = true;
-}
-
-static void kvmppc_start_restoring_l2_cache(const struct kvmppc_vcore *vc)
-{
-	phys_addr_t phy_addr, mpp_addr;
-
-	phy_addr = virt_to_phys(vc->mpp_buffer);
-	mpp_addr = phy_addr & PPC_MPPE_ADDRESS_MASK;
-
-	/* We must abort any in-progress save operations to ensure
-	 * the table is valid so that prefetch engine knows when to
-	 * stop prefetching. */
-	logmpp(mpp_addr | PPC_LOGMPP_LOG_ABORT);
-	mtspr(SPRN_MPPR, mpp_addr | PPC_MPPR_FETCH_WHOLE_TABLE);
 }
 
 /*
···
 
 	srcu_idx = srcu_read_lock(&vc->kvm->srcu);
 
-	if (vc->mpp_buffer_is_valid)
-		kvmppc_start_restoring_l2_cache(vc);
-
 	__kvmppc_vcore_entry();
-
-	if (vc->mpp_buffer)
-		kvmppc_start_saving_l2_cache(vc);
 
 	srcu_read_unlock(&vc->kvm->srcu, srcu_idx);
 
···
 {
 	long int i;
 
-	for (i = 0; i < KVM_MAX_VCORES; ++i) {
-		if (kvm->arch.vcores[i] && kvm->arch.vcores[i]->mpp_buffer) {
-			struct kvmppc_vcore *vc = kvm->arch.vcores[i];
-			free_pages((unsigned long)vc->mpp_buffer,
-				   MPP_BUFFER_ORDER);
-		}
+	for (i = 0; i < KVM_MAX_VCORES; ++i)
 		kfree(kvm->arch.vcores[i]);
-	}
 	kvm->arch.online_vcores = 0;
 }
 

arch/powerpc/platforms/powernv/smp.c

···
 	 * so clear LPCR:PECE1. We keep PECE2 enabled.
 	 */
 	mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) & ~(u64)LPCR_PECE1);
+
+	/*
+	 * Hard-disable interrupts, and then clear irq_happened flags
+	 * that we can safely ignore while off-line, since they
+	 * are for things for which we do no processing when off-line
+	 * (or in the case of HMI, all the processing we need to do
+	 * is done in lower-level real-mode code).
+	 */
+	hard_irq_disable();
+	local_paca->irq_happened &= ~(PACA_IRQ_DEC | PACA_IRQ_HMI);
+
 	while (!generic_check_cpu_restart(cpu)) {
+		/*
+		 * Clear IPI flag, since we don't handle IPIs while
+		 * offline, except for those when changing micro-threading
+		 * mode, which are handled explicitly below, and those
+		 * for coming online, which are handled via
+		 * generic_check_cpu_restart() calls.
+		 */
+		kvmppc_set_host_ipi(cpu, 0);
 
 		ppc64_runlatch_off();
 
···
 		 * having finished executing in a KVM guest, then srr1
 		 * contains 0.
 		 */
-		if ((srr1 & wmask) == SRR1_WAKEEE) {
+		if (((srr1 & wmask) == SRR1_WAKEEE) ||
+		    (local_paca->irq_happened & PACA_IRQ_EE)) {
 			icp_native_flush_interrupt();
-			local_paca->irq_happened &= PACA_IRQ_HARD_DIS;
-			smp_mb();
 		} else if ((srr1 & wmask) == SRR1_WAKEHDBELL) {
 			unsigned long msg = PPC_DBELL_TYPE(PPC_DBELL_SERVER);
 			asm volatile(PPC_MSGCLR(%0) : : "r" (msg));
-			kvmppc_set_host_ipi(cpu, 0);
 		}
+		local_paca->irq_happened &= ~(PACA_IRQ_EE | PACA_IRQ_DBELL);
+		smp_mb();
 
 		if (cpu_core_split_required())
 			continue;
 
-		if (!generic_check_cpu_restart(cpu))
+		if (srr1 && !generic_check_cpu_restart(cpu))
 			DBG("CPU%d Unexpected exit while offline !\n", cpu);
 	}
 	mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) | LPCR_PECE1);