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"

7 files changed, 28 insertions, 86 deletions

diff --git a/arch/powerpc/include/asm/cache.h b/arch/powerpc/include/asm/cache.h
index 0dc42c5082b7..5f8229e24fe6 100644
--- a/arch/powerpc/include/asm/cache.h
+++ b/arch/powerpc/include/asm/cache.h
@@ -3,7 +3,6 @@
 
 #ifdef __KERNEL__
 
-#include <asm/reg.h>
 
 /* bytes per L1 cache line */
 #if defined(CONFIG_8xx) || defined(CONFIG_403GCX)
@@ -40,12 +39,6 @@ struct ppc64_caches {
 };
 
 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__)
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 827a38d7a9db..887c259556df 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -297,8 +297,6 @@ struct kvmppc_vcore {
         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;
 };
 
diff --git a/arch/powerpc/include/asm/ppc-opcode.h b/arch/powerpc/include/asm/ppc-opcode.h
index 790f5d1d9a46..7ab04fc59e24 100644
--- a/arch/powerpc/include/asm/ppc-opcode.h
+++ b/arch/powerpc/include/asm/ppc-opcode.h
@@ -141,7 +141,6 @@
 #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
@@ -285,20 +284,6 @@
 #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))
@@ -307,8 +292,6 @@
 #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))
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index aa1cc5f015ee..a908ada8e0a5 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -226,7 +226,6 @@
 #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
diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c
index 84bf934cf748..5a753fae8265 100644
--- a/arch/powerpc/kernel/rtas.c
+++ b/arch/powerpc/kernel/rtas.c
@@ -1043,6 +1043,9 @@ asmlinkage int ppc_rtas(struct rtas_args __user *uargs)
         if (!capable(CAP_SYS_ADMIN))
                 return -EPERM;
 
+        if (!rtas.entry)
+                return -EINVAL;
+
         if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0)
                 return -EFAULT;
 
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 228049786888..9c26c5a96ea2 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -36,7 +36,6 @@
 
 #include <asm/reg.h>
 #include <asm/cputable.h>
-#include <asm/cache.h>
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
 #include <asm/uaccess.h>
@@ -75,12 +74,6 @@
 
 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);
 MODULE_PARM_DESC(dynamic_mt_modes, "Set of allowed dynamic micro-threading modes: 0 (= none), 2, 4, or 6 (= 2 or 4)");
@@ -1455,13 +1448,6 @@ static struct kvmppc_vcore *kvmppc_vcore_create(struct kvm *kvm, int core)
         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;
 }
 
@@ -1894,33 +1880,6 @@ static int on_primary_thread(void)
         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);
-}
-
 /*
  * A list of virtual cores for each physical CPU.
  * These are vcores that could run but their runner VCPU tasks are
@@ -2471,14 +2430,8 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
 
         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);
 
         spin_lock(&vc->lock);
@@ -3073,14 +3026,8 @@ static void kvmppc_free_vcores(struct kvm *kvm)
 {
         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;
 }
 
diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/powernv/smp.c
index 8f70ba681a78..ca264833ee64 100644
--- a/arch/powerpc/platforms/powernv/smp.c
+++ b/arch/powerpc/platforms/powernv/smp.c
@@ -171,7 +171,26 @@ static void pnv_smp_cpu_kill_self(void)
          * 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();
 
@@ -196,20 +215,20 @@ static void pnv_smp_cpu_kill_self(void)
                  * 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);