13 files changed, 163 insertions, 154 deletions

diff --git a/arch/tile/kernel/entry.S b/arch/tile/kernel/entry.S
index fd8dc42abdcb..431e9ae60488 100644
--- a/arch/tile/kernel/entry.S
+++ b/arch/tile/kernel/entry.S
@@ -38,12 +38,6 @@ STD_ENTRY(kernel_execve)
         jrp lr
         STD_ENDPROC(kernel_execve)
 
-/* Delay a fixed number of cycles. */
-STD_ENTRY(__delay)
-        { addi r0, r0, -1; bnzt r0, . }
-        jrp lr
-        STD_ENDPROC(__delay)
-
 /*
  * We don't run this function directly, but instead copy it to a page
  * we map into every user process.  See vdso_setup().
@@ -97,23 +91,17 @@ STD_ENTRY(smp_nap)
 
 /*
  * Enable interrupts racelessly and then nap until interrupted.
+ * Architecturally, we are guaranteed that enabling interrupts via
+ * mtspr to INTERRUPT_CRITICAL_SECTION only interrupts at the next PC.
  * This function's _cpu_idle_nap address is special; see intvec.S.
  * When interrupted at _cpu_idle_nap, we bump the PC forward 8, and
  * as a result return to the function that called _cpu_idle().
  */
 STD_ENTRY(_cpu_idle)
-        {
-         lnk r0
-         movei r1, KERNEL_PL
-        }
-        {
-         addli r0, r0, _cpu_idle_nap - .
-         mtspr INTERRUPT_CRITICAL_SECTION, r1
-        }
+        movei r1, 1
+        mtspr INTERRUPT_CRITICAL_SECTION, r1
         IRQ_ENABLE(r2, r3)             /* unmask, but still with ICS set */
-        mtspr SPR_EX_CONTEXT_K_1, r1   /* Kernel PL, ICS clear */
-        mtspr SPR_EX_CONTEXT_K_0, r0
-        iret
+        mtspr INTERRUPT_CRITICAL_SECTION, zero
         .global _cpu_idle_nap
 _cpu_idle_nap:
         nap
diff --git a/arch/tile/kernel/head_32.S b/arch/tile/kernel/head_32.S
index 90e7c4435693..1a39b7c1c87e 100644
--- a/arch/tile/kernel/head_32.S
+++ b/arch/tile/kernel/head_32.S
@@ -133,7 +133,7 @@ ENTRY(_start)
         }
         ENDPROC(_start)
 
-.section ".bss.page_aligned","w"
+__PAGE_ALIGNED_BSS
         .align PAGE_SIZE
 ENTRY(empty_zero_page)
         .fill PAGE_SIZE,1,0
@@ -145,10 +145,10 @@ ENTRY(empty_zero_page)
         .endif
         .word HV_PTE_PAGE | HV_PTE_DIRTY | HV_PTE_PRESENT | HV_PTE_ACCESSED | \
               (HV_PTE_MODE_CACHE_NO_L3 << HV_PTE_INDEX_MODE)
-        .word (\bits1) | (HV_CPA_TO_PFN(\cpa) << HV_PTE_INDEX_PFN)
+        .word (\bits1) | (HV_CPA_TO_PFN(\cpa) << (HV_PTE_INDEX_PFN - 32))
         .endm
 
-.section ".data.page_aligned","wa"
+__PAGE_ALIGNED_DATA
         .align PAGE_SIZE
 ENTRY(swapper_pg_dir)
         /*
@@ -158,12 +158,14 @@ ENTRY(swapper_pg_dir)
          */
         .set addr, 0
         .rept (MEM_USER_INTRPT - PAGE_OFFSET) >> PGDIR_SHIFT
-        PTE addr + PAGE_OFFSET, addr, HV_PTE_READABLE | HV_PTE_WRITABLE
+        PTE addr + PAGE_OFFSET, addr, (1 << (HV_PTE_INDEX_READABLE - 32)) | \
+                                      (1 << (HV_PTE_INDEX_WRITABLE - 32))
         .set addr, addr + PGDIR_SIZE
         .endr
 
         /* The true text VAs are mapped as VA = PA + MEM_SV_INTRPT */
-        PTE MEM_SV_INTRPT, 0, HV_PTE_READABLE | HV_PTE_EXECUTABLE
+        PTE MEM_SV_INTRPT, 0, (1 << (HV_PTE_INDEX_READABLE - 32)) | \
+                              (1 << (HV_PTE_INDEX_EXECUTABLE - 32))
         .org swapper_pg_dir + HV_L1_SIZE
         END(swapper_pg_dir)
 
@@ -176,6 +178,7 @@ ENTRY(swapper_pg_dir)
         __INITDATA
         .align CHIP_L2_LINE_SIZE()
 ENTRY(swapper_pgprot)
-        PTE     0, 0, HV_PTE_READABLE | HV_PTE_WRITABLE, 1
+        PTE     0, 0, (1 << (HV_PTE_INDEX_READABLE - 32)) | \
+                      (1 << (HV_PTE_INDEX_WRITABLE - 32)), 1
         .align CHIP_L2_LINE_SIZE()
         END(swapper_pgprot)
diff --git a/arch/tile/kernel/intvec_32.S b/arch/tile/kernel/intvec_32.S
index 5eed4a02bf62..fffcfa6b3a62 100644
--- a/arch/tile/kernel/intvec_32.S
+++ b/arch/tile/kernel/intvec_32.S
@@ -32,10 +32,6 @@
 # error "No support for kernel preemption currently"
 #endif
 
-#if INT_INTCTRL_K < 32 || INT_INTCTRL_K >= 48
-# error INT_INTCTRL_K coded to set high interrupt mask
-#endif
-
 #define PTREGS_PTR(reg, ptreg) addli reg, sp, C_ABI_SAVE_AREA_SIZE + (ptreg)
 
 #define PTREGS_OFFSET_SYSCALL PTREGS_OFFSET_REG(TREG_SYSCALL_NR)
@@ -1199,46 +1195,6 @@ STD_ENTRY(interrupt_return)
         STD_ENDPROC(interrupt_return)
 
         /*
-         * This interrupt variant clears the INT_INTCTRL_K interrupt mask bit
-         * before returning, so we can properly get more downcalls.
-         */
-        .pushsection .text.handle_interrupt_downcall,"ax"
-handle_interrupt_downcall:
-        finish_interrupt_save handle_interrupt_downcall
-        check_single_stepping normal, .Ldispatch_downcall
-.Ldispatch_downcall:
-
-        /* Clear INTCTRL_K from the set of interrupts we ever enable. */
-        GET_INTERRUPTS_ENABLED_MASK_PTR(r30)
-        {
-         addi   r30, r30, 4
-         movei  r31, INT_MASK(INT_INTCTRL_K)
-        }
-        {
-         lw     r20, r30
-         nor    r21, r31, zero
-        }
-        and     r20, r20, r21
-        sw      r30, r20
-
-        {
-         jalr   r0
-         PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
-        }
-        FEEDBACK_REENTER(handle_interrupt_downcall)
-
-        /* Allow INTCTRL_K to be enabled next time we enable interrupts. */
-        lw      r20, r30
-        or      r20, r20, r31
-        sw      r30, r20
-
-        {
-         movei  r30, 0   /* not an NMI */
-         j      interrupt_return
-        }
-        STD_ENDPROC(handle_interrupt_downcall)
-
-        /*
          * Some interrupts don't check for single stepping
          */
         .pushsection .text.handle_interrupt_no_single_step,"ax"
@@ -1600,7 +1556,10 @@ STD_ENTRY(_sys_clone)
         .align 64
         /* Align much later jump on the start of a cache line. */
 #if !ATOMIC_LOCKS_FOUND_VIA_TABLE()
-        nop; nop
+        nop
+#if PAGE_SIZE >= 0x10000
+        nop
+#endif
 #endif
 ENTRY(sys_cmpxchg)
 
@@ -1628,9 +1587,13 @@ ENTRY(sys_cmpxchg)
          * about aliasing among multiple mappings of the same physical page,
          * and we ignore the low 3 bits so we have one lock that covers
          * both a cmpxchg64() and a cmpxchg() on either its low or high word.
-         * NOTE: this code must match __atomic_hashed_lock() in lib/atomic.c.
+         * NOTE: this must match __atomic_hashed_lock() in lib/atomic_32.c.
          */
 
+#if (PAGE_OFFSET & 0xffff) != 0
+# error Code here assumes PAGE_OFFSET can be loaded with just hi16()
+#endif
+
 #if ATOMIC_LOCKS_FOUND_VIA_TABLE()
         {
          /* Check for unaligned input. */
@@ -1723,11 +1686,14 @@ ENTRY(sys_cmpxchg)
          lw     r26, r0
         }
         {
-         /* atomic_locks is page aligned so this suffices to get its addr. */
-         auli   r21, zero, hi16(atomic_locks)
+         auli   r21, zero, ha16(atomic_locks)
 
          bbns   r23, .Lcmpxchg_badaddr
         }
+#if PAGE_SIZE < 0x10000
+        /* atomic_locks is page-aligned so for big pages we don't need this. */
+        addli   r21, r21, lo16(atomic_locks)
+#endif
         {
          /*
           * Insert the hash bits into the page-aligned pointer.
@@ -1762,7 +1728,7 @@ ENTRY(sys_cmpxchg)
 
         /*
          * Perform the actual cmpxchg or atomic_update.
-         * Note that __futex_mark_unlocked() in uClibc relies on
+         * Note that the system <arch/atomic.h> header relies on
          * atomic_update() to always perform an "mf", so don't make
          * it optional or conditional without modifying that code.
          */
@@ -2014,17 +1980,17 @@ int_unalign:
 #endif
         int_hand     INT_INTCTRL_0, INTCTRL_0, bad_intr
         int_hand     INT_MESSAGE_RCV_DWNCL, MESSAGE_RCV_DWNCL, \
-                     hv_message_intr, handle_interrupt_downcall
+                     hv_message_intr
         int_hand     INT_DEV_INTR_DWNCL, DEV_INTR_DWNCL, \
-                     tile_dev_intr, handle_interrupt_downcall
+                     tile_dev_intr
         int_hand     INT_I_ASID, I_ASID, bad_intr
         int_hand     INT_D_ASID, D_ASID, bad_intr
         int_hand     INT_DMATLB_MISS_DWNCL, DMATLB_MISS_DWNCL, \
-                     do_page_fault, handle_interrupt_downcall
+                     do_page_fault
         int_hand     INT_SNITLB_MISS_DWNCL, SNITLB_MISS_DWNCL, \
-                     do_page_fault, handle_interrupt_downcall
+                     do_page_fault
         int_hand     INT_DMATLB_ACCESS_DWNCL, DMATLB_ACCESS_DWNCL, \
-                     do_page_fault, handle_interrupt_downcall
+                     do_page_fault
         int_hand     INT_SN_CPL, SN_CPL, bad_intr
         int_hand     INT_DOUBLE_FAULT, DOUBLE_FAULT, do_trap
 #if CHIP_HAS_AUX_PERF_COUNTERS()
diff --git a/arch/tile/kernel/irq.c b/arch/tile/kernel/irq.c
index 128805ef8f2c..0baa7580121f 100644
--- a/arch/tile/kernel/irq.c
+++ b/arch/tile/kernel/irq.c
@@ -176,43 +176,43 @@ void disable_percpu_irq(unsigned int irq)
 EXPORT_SYMBOL(disable_percpu_irq);
 
 /* Mask an interrupt. */
-static void tile_irq_chip_mask(unsigned int irq)
+static void tile_irq_chip_mask(struct irq_data *d)
 {
-        mask_irqs(1UL << irq);
+        mask_irqs(1UL << d->irq);
 }
 
 /* Unmask an interrupt. */
-static void tile_irq_chip_unmask(unsigned int irq)
+static void tile_irq_chip_unmask(struct irq_data *d)
 {
-        unmask_irqs(1UL << irq);
+        unmask_irqs(1UL << d->irq);
 }
 
 /*
  * Clear an interrupt before processing it so that any new assertions
  * will trigger another irq.
  */
-static void tile_irq_chip_ack(unsigned int irq)
+static void tile_irq_chip_ack(struct irq_data *d)
 {
-        if ((unsigned long)get_irq_chip_data(irq) != IS_HW_CLEARED)
-                clear_irqs(1UL << irq);
+        if ((unsigned long)irq_data_get_irq_chip_data(d) != IS_HW_CLEARED)
+                clear_irqs(1UL << d->irq);
 }
 
 /*
  * For per-cpu interrupts, we need to avoid unmasking any interrupts
  * that we disabled via disable_percpu_irq().
  */
-static void tile_irq_chip_eoi(unsigned int irq)
+static void tile_irq_chip_eoi(struct irq_data *d)
 {
-        if (!(__get_cpu_var(irq_disable_mask) & (1UL << irq)))
-                unmask_irqs(1UL << irq);
+        if (!(__get_cpu_var(irq_disable_mask) & (1UL << d->irq)))
+                unmask_irqs(1UL << d->irq);
 }
 
 static struct irq_chip tile_irq_chip = {
         .name = "tile_irq_chip",
-        .ack = tile_irq_chip_ack,
-        .eoi = tile_irq_chip_eoi,
-        .mask = tile_irq_chip_mask,
-        .unmask = tile_irq_chip_unmask,
+        .irq_ack = tile_irq_chip_ack,
+        .irq_eoi = tile_irq_chip_eoi,
+        .irq_mask = tile_irq_chip_mask,
+        .irq_unmask = tile_irq_chip_unmask,
 };
 
 void __init init_IRQ(void)
@@ -277,8 +277,10 @@ int show_interrupts(struct seq_file *p, void *v)
         }
 
         if (i < NR_IRQS) {
-                raw_spin_lock_irqsave(&irq_desc[i].lock, flags);
-                action = irq_desc[i].action;
+                struct irq_desc *desc = irq_to_desc(i);
+
+                raw_spin_lock_irqsave(&desc->lock, flags);
+                action = desc->action;
                 if (!action)
                         goto skip;
                 seq_printf(p, "%3d: ", i);
@@ -288,7 +290,7 @@ int show_interrupts(struct seq_file *p, void *v)
                 for_each_online_cpu(j)
                         seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 #endif
-                seq_printf(p, " %14s", irq_desc[i].chip->name);
+                seq_printf(p, " %14s", get_irq_desc_chip(desc)->name);
                 seq_printf(p, "  %s", action->name);
 
                 for (action = action->next; action; action = action->next)
@@ -296,7 +298,7 @@ int show_interrupts(struct seq_file *p, void *v)
 
                 seq_putc(p, '\n');
 skip:
-                raw_spin_unlock_irqrestore(&irq_desc[i].lock, flags);
+                raw_spin_unlock_irqrestore(&desc->lock, flags);
         }
         return 0;
 }
diff --git a/arch/tile/kernel/machine_kexec.c b/arch/tile/kernel/machine_kexec.c
index 0d8b9e933487..e00d7179989e 100644
--- a/arch/tile/kernel/machine_kexec.c
+++ b/arch/tile/kernel/machine_kexec.c
@@ -240,8 +240,11 @@ static void setup_quasi_va_is_pa(void)
         pte = hv_pte(_PAGE_KERNEL | _PAGE_HUGE_PAGE);
         pte = hv_pte_set_mode(pte, HV_PTE_MODE_CACHE_NO_L3);
 
-        for (i = 0; i < pgd_index(PAGE_OFFSET); i++)
-                pgtable[i] = pfn_pte(i << (HPAGE_SHIFT - PAGE_SHIFT), pte);
+        for (i = 0; i < pgd_index(PAGE_OFFSET); i++) {
+                unsigned long pfn = i << (HPAGE_SHIFT - PAGE_SHIFT);
+                if (pfn_valid(pfn))
+                        __set_pte(&pgtable[i], pfn_pte(pfn, pte));
+        }
 }
 
 
diff --git a/arch/tile/kernel/pci-dma.c b/arch/tile/kernel/pci-dma.c
index 5ad5e13b0fa6..658752b2835e 100644
--- a/arch/tile/kernel/pci-dma.c
+++ b/arch/tile/kernel/pci-dma.c
@@ -86,6 +86,21 @@ EXPORT_SYMBOL(dma_free_coherent);
  * can count on nothing having been touched.
  */
 
+/* Flush a PA range from cache page by page. */
+static void __dma_map_pa_range(dma_addr_t dma_addr, size_t size)
+{
+        struct page *page = pfn_to_page(PFN_DOWN(dma_addr));
+        size_t bytesleft = PAGE_SIZE - (dma_addr & (PAGE_SIZE - 1));
+
+        while ((ssize_t)size > 0) {
+                /* Flush the page. */
+                homecache_flush_cache(page++, 0);
+
+                /* Figure out if we need to continue on the next page. */
+                size -= bytesleft;
+                bytesleft = PAGE_SIZE;
+        }
+}
 
 /*
  * dma_map_single can be passed any memory address, and there appear
@@ -97,26 +112,12 @@ EXPORT_SYMBOL(dma_free_coherent);
 dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size,
                enum dma_data_direction direction)
 {
-        struct page *page;
-        dma_addr_t dma_addr;
-        int thispage;
+        dma_addr_t dma_addr = __pa(ptr);
 
         BUG_ON(!valid_dma_direction(direction));
         WARN_ON(size == 0);
 
-        dma_addr = __pa(ptr);
-
-        /* We might have been handed a buffer that wraps a page boundary */
-        while ((int)size > 0) {
-                /* The amount to flush that's on this page */
-                thispage = PAGE_SIZE - ((unsigned long)ptr & (PAGE_SIZE - 1));
-                thispage = min((int)thispage, (int)size);
-                /* Is this valid for any page we could be handed? */
-                page = pfn_to_page(kaddr_to_pfn(ptr));
-                homecache_flush_cache(page, 0);
-                ptr += thispage;
-                size -= thispage;
-        }
+        __dma_map_pa_range(dma_addr, size);
 
         return dma_addr;
 }
@@ -140,10 +141,8 @@ int dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents,
         WARN_ON(nents == 0 || sglist->length == 0);
 
         for_each_sg(sglist, sg, nents, i) {
-                struct page *page;
                 sg->dma_address = sg_phys(sg);
-                page = pfn_to_page(sg->dma_address >> PAGE_SHIFT);
-                homecache_flush_cache(page, 0);
+                __dma_map_pa_range(sg->dma_address, sg->length);
         }
 
         return nents;
@@ -163,6 +162,7 @@ dma_addr_t dma_map_page(struct device *dev, struct page *page,
 {
         BUG_ON(!valid_dma_direction(direction));
 
+        BUG_ON(offset + size > PAGE_SIZE);
         homecache_flush_cache(page, 0);
 
         return page_to_pa(page) + offset;
diff --git a/arch/tile/kernel/process.c b/arch/tile/kernel/process.c
index e90eb53173b0..b9cd962e1d30 100644
--- a/arch/tile/kernel/process.c
+++ b/arch/tile/kernel/process.c
@@ -165,7 +165,7 @@ void free_thread_info(struct thread_info *info)
                 kfree(step_state);
         }
 
-        free_page((unsigned long)info);
+        free_pages((unsigned long)info, THREAD_SIZE_ORDER);
 }
 
 static void save_arch_state(struct thread_struct *t);
@@ -574,6 +574,8 @@ SYSCALL_DEFINE4(execve, const char __user *, path,
                 goto out;
         error = do_execve(filename, argv, envp, regs);
         putname(filename);
+        if (error == 0)
+                single_step_execve();
 out:
         return error;
 }
@@ -593,6 +595,8 @@ long compat_sys_execve(const char __user *path,
                 goto out;
         error = compat_do_execve(filename, argv, envp, regs);
         putname(filename);
+        if (error == 0)
+                single_step_execve();
 out:
         return error;
 }
diff --git a/arch/tile/kernel/setup.c b/arch/tile/kernel/setup.c
index f18573643ed1..3696b1832566 100644
--- a/arch/tile/kernel/setup.c
+++ b/arch/tile/kernel/setup.c
@@ -59,6 +59,8 @@ unsigned long __initdata node_memmap_pfn[MAX_NUMNODES];
 unsigned long __initdata node_percpu_pfn[MAX_NUMNODES];
 unsigned long __initdata node_free_pfn[MAX_NUMNODES];
 
+static unsigned long __initdata node_percpu[MAX_NUMNODES];
+
 #ifdef CONFIG_HIGHMEM
 /* Page frame index of end of lowmem on each controller. */
 unsigned long __cpuinitdata node_lowmem_end_pfn[MAX_NUMNODES];
@@ -554,7 +556,6 @@ static void __init setup_bootmem_allocator(void)
                 reserve_bootmem(crashk_res.start,
                         crashk_res.end - crashk_res.start + 1, 0);
 #endif
-
 }
 
 void *__init alloc_remap(int nid, unsigned long size)
@@ -568,11 +569,13 @@ void *__init alloc_remap(int nid, unsigned long size)
 
 static int __init percpu_size(void)
 {
-        int size = ALIGN(__per_cpu_end - __per_cpu_start, PAGE_SIZE);
-#ifdef CONFIG_MODULES
-        if (size < PERCPU_ENOUGH_ROOM)
-                size = PERCPU_ENOUGH_ROOM;
-#endif
+        int size = __per_cpu_end - __per_cpu_start;
+        size += PERCPU_MODULE_RESERVE;
+        size += PERCPU_DYNAMIC_EARLY_SIZE;
+        if (size < PCPU_MIN_UNIT_SIZE)
+                size = PCPU_MIN_UNIT_SIZE;
+        size = roundup(size, PAGE_SIZE);
+
         /* In several places we assume the per-cpu data fits on a huge page. */
         BUG_ON(kdata_huge && size > HPAGE_SIZE);
         return size;
@@ -589,7 +592,6 @@ static inline unsigned long alloc_bootmem_pfn(int size, unsigned long goal)
 static void __init zone_sizes_init(void)
 {
         unsigned long zones_size[MAX_NR_ZONES] = { 0 };
-        unsigned long node_percpu[MAX_NUMNODES] = { 0 };
         int size = percpu_size();
         int num_cpus = smp_height * smp_width;
         int i;
@@ -674,7 +676,7 @@ static void __init zone_sizes_init(void)
                 NODE_DATA(i)->bdata = NODE_DATA(0)->bdata;
 
                 free_area_init_node(i, zones_size, start, NULL);
-                printk(KERN_DEBUG "  DMA zone: %ld per-cpu pages\n",
+                printk(KERN_DEBUG "  Normal zone: %ld per-cpu pages\n",
                        PFN_UP(node_percpu[i]));
 
                 /* Track the type of memory on each node */
@@ -1312,6 +1314,8 @@ static void *__init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
 
         BUG_ON(size % PAGE_SIZE != 0);
         pfn_offset[nid] += size / PAGE_SIZE;
+        BUG_ON(node_percpu[nid] < size);
+        node_percpu[nid] -= size;
         if (percpu_pfn[cpu] == 0)
                 percpu_pfn[cpu] = pfn;
         return pfn_to_kaddr(pfn);
diff --git a/arch/tile/kernel/single_step.c b/arch/tile/kernel/single_step.c
index 1eb3b39e36c7..84a729e06ec4 100644
--- a/arch/tile/kernel/single_step.c
+++ b/arch/tile/kernel/single_step.c
@@ -56,7 +56,7 @@ enum mem_op {
         MEMOP_STORE_POSTINCR
 };
 
-static inline tile_bundle_bits set_BrOff_X1(tile_bundle_bits n, int32_t offset)
+static inline tile_bundle_bits set_BrOff_X1(tile_bundle_bits n, s32 offset)
 {
         tile_bundle_bits result;
 
@@ -254,6 +254,18 @@ P("\n");
         return bundle;
 }
 
+/*
+ * Called after execve() has started the new image.  This allows us
+ * to reset the info state.  Note that the the mmap'ed memory, if there
+ * was any, has already been unmapped by the exec.
+ */
+void single_step_execve(void)
+{
+        struct thread_info *ti = current_thread_info();
+        kfree(ti->step_state);
+        ti->step_state = NULL;
+}
+
 /**
  * single_step_once() - entry point when single stepping has been triggered.
  * @regs: The machine register state
@@ -373,7 +385,7 @@ void single_step_once(struct pt_regs *regs)
                 /* branches */
                 case BRANCH_OPCODE_X1:
                 {
-                        int32_t offset = signExtend17(get_BrOff_X1(bundle));
+                        s32 offset = signExtend17(get_BrOff_X1(bundle));
 
                         /*
                          * For branches, we use a rewriting trick to let the
@@ -731,4 +743,9 @@ void single_step_once(struct pt_regs *regs)
         __insn_mtspr(SPR_SINGLE_STEP_EN_K_K, 1 << USER_PL);
 }
 
+void single_step_execve(void)
+{
+        /* Nothing */
+}
+
 #endif /* !__tilegx__ */
diff --git a/arch/tile/kernel/smp.c b/arch/tile/kernel/smp.c
index 9575b37a8b75..a4293102ef81 100644
--- a/arch/tile/kernel/smp.c
+++ b/arch/tile/kernel/smp.c
@@ -36,6 +36,22 @@ static unsigned long __iomem *ipi_mappings[NR_CPUS];
 /* Set by smp_send_stop() to avoid recursive panics. */
 static int stopping_cpus;
 
+static void __send_IPI_many(HV_Recipient *recip, int nrecip, int tag)
+{
+        int sent = 0;
+        while (sent < nrecip) {
+                int rc = hv_send_message(recip, nrecip,
+                                         (HV_VirtAddr)&tag, sizeof(tag));
+                if (rc < 0) {
+                        if (!stopping_cpus)  /* avoid recursive panic */
+                                panic("hv_send_message returned %d", rc);
+                        break;
+                }
+                WARN_ONCE(rc == 0, "hv_send_message() returned zero\n");
+                sent += rc;
+        }
+}
+
 void send_IPI_single(int cpu, int tag)
 {
         HV_Recipient recip = {
@@ -43,14 +59,13 @@ void send_IPI_single(int cpu, int tag)
                 .x = cpu % smp_width,
                 .state = HV_TO_BE_SENT
         };
-        int rc = hv_send_message(&recip, 1, (HV_VirtAddr)&tag, sizeof(tag));
-        BUG_ON(rc <= 0);
+        __send_IPI_many(&recip, 1, tag);
 }
 
 void send_IPI_many(const struct cpumask *mask, int tag)
 {
         HV_Recipient recip[NR_CPUS];
-        int cpu, sent;
+        int cpu;
         int nrecip = 0;
         int my_cpu = smp_processor_id();
         for_each_cpu(cpu, mask) {
@@ -61,17 +76,7 @@ void send_IPI_many(const struct cpumask *mask, int tag)
                 r->x = cpu % smp_width;
                 r->state = HV_TO_BE_SENT;
         }
-        sent = 0;
-        while (sent < nrecip) {
-                int rc = hv_send_message(recip, nrecip,
-                                         (HV_VirtAddr)&tag, sizeof(tag));
-                if (rc <= 0) {
-                        if (!stopping_cpus)  /* avoid recursive panic */
-                                panic("hv_send_message returned %d", rc);
-                        break;
-                }
-                sent += rc;
-        }
+        __send_IPI_many(recip, nrecip, tag);
 }
 
 void send_IPI_allbutself(int tag)
diff --git a/arch/tile/kernel/stack.c b/arch/tile/kernel/stack.c
index 0d54106be3d6..dd81713a90dc 100644
--- a/arch/tile/kernel/stack.c
+++ b/arch/tile/kernel/stack.c
@@ -44,13 +44,6 @@ static int in_kernel_stack(struct KBacktraceIterator *kbt, VirtualAddress sp)
         return sp >= kstack_base && sp < kstack_base + THREAD_SIZE;
 }
 
-/* Is address in the specified kernel code? */
-static int in_kernel_text(VirtualAddress address)
-{
-        return (address >= MEM_SV_INTRPT &&
-                address < MEM_SV_INTRPT + HPAGE_SIZE);
-}
-
 /* Is address valid for reading? */
 static int valid_address(struct KBacktraceIterator *kbt, VirtualAddress address)
 {
@@ -63,6 +56,23 @@ static int valid_address(struct KBacktraceIterator *kbt, VirtualAddress address)
         if (l1_pgtable == NULL)
                 return 0;       /* can't read user space in other tasks */
 
+#ifdef CONFIG_64BIT
+        /* Find the real l1_pgtable by looking in the l0_pgtable. */
+        pte = l1_pgtable[HV_L0_INDEX(address)];
+        if (!hv_pte_get_present(pte))
+                return 0;
+        pfn = hv_pte_get_pfn(pte);
+        if (pte_huge(pte)) {
+                if (!pfn_valid(pfn)) {
+                        pr_err("L0 huge page has bad pfn %#lx\n", pfn);
+                        return 0;
+                }
+                return hv_pte_get_present(pte) && hv_pte_get_readable(pte);
+        }
+        page = pfn_to_page(pfn);
+        BUG_ON(PageHighMem(page));  /* No HIGHMEM on 64-bit. */
+        l1_pgtable = (HV_PTE *)pfn_to_kaddr(pfn);
+#endif
         pte = l1_pgtable[HV_L1_INDEX(address)];
         if (!hv_pte_get_present(pte))
                 return 0;
@@ -92,7 +102,7 @@ static bool read_memory_func(void *result, VirtualAddress address,
 {
         int retval;
         struct KBacktraceIterator *kbt = (struct KBacktraceIterator *)vkbt;
-        if (in_kernel_text(address)) {
+        if (__kernel_text_address(address)) {
                 /* OK to read kernel code. */
         } else if (address >= PAGE_OFFSET) {
                 /* We only tolerate kernel-space reads of this task's stack */
@@ -132,7 +142,7 @@ static struct pt_regs *valid_fault_handler(struct KBacktraceIterator* kbt)
                 }
         }
         if (EX1_PL(p->ex1) == KERNEL_PL &&
-            in_kernel_text(p->pc) &&
+            __kernel_text_address(p->pc) &&
             in_kernel_stack(kbt, p->sp) &&
             p->sp >= sp) {
                 if (kbt->verbose)
diff --git a/arch/tile/kernel/time.c b/arch/tile/kernel/time.c
index f2e156e44692..49a605be94c5 100644
--- a/arch/tile/kernel/time.c
+++ b/arch/tile/kernel/time.c
@@ -224,3 +224,13 @@ int setup_profiling_timer(unsigned int multiplier)
 {
         return -EINVAL;
 }
+
+/*
+ * Use the tile timer to convert nsecs to core clock cycles, relying
+ * on it having the same frequency as SPR_CYCLE.
+ */
+cycles_t ns2cycles(unsigned long nsecs)
+{
+        struct clock_event_device *dev = &__get_cpu_var(tile_timer);
+        return ((u64)nsecs * dev->mult) >> dev->shift;
+}
diff --git a/arch/tile/kernel/vmlinux.lds.S b/arch/tile/kernel/vmlinux.lds.S
index c6ce378e0678..38f64fafdc10 100644
--- a/arch/tile/kernel/vmlinux.lds.S
+++ b/arch/tile/kernel/vmlinux.lds.S
@@ -59,10 +59,7 @@ SECTIONS
 
   . = ALIGN(PAGE_SIZE);
   VMLINUX_SYMBOL(_sinitdata) = .;
-  .init.page : AT (ADDR(.init.page) - LOAD_OFFSET) {
-    *(.init.page)
-  } :data =0
-  INIT_DATA_SECTION(16)
+  INIT_DATA_SECTION(16) :data =0
   PERCPU(L2_CACHE_BYTES, PAGE_SIZE)
   . = ALIGN(PAGE_SIZE);
   VMLINUX_SYMBOL(_einitdata) = .;