Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile

* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: (27 commits)
  arch/tile: support newer binutils assembler shift semantics
  arch/tile: fix deadlock bugs in rwlock implementation
  drivers/edac: provide support for tile architecture
  tile on-chip network driver: sync up with latest fixes
  arch/tile: support 4KB page size as well as 64KB
  arch/tile: add some more VMSPLIT options and use consistent naming
  arch/tile: fix some comments and whitespace
  arch/tile: export some additional module symbols
  arch/tile: enhance existing finv_buffer_remote() routine
  arch/tile: fix two bugs in the backtracer code
  arch/tile: use extended assembly to inline __mb_incoherent()
  arch/tile: use a cleaner technique to enable interrupt for cpu_idle()
  arch/tile: sync up with <arch/sim.h> and <arch/sim_def.h> changes
  arch/tile: fix reversed test of strict_strtol() return value
  arch/tile: avoid a simulator warning during bootup
  arch/tile: export <asm/hardwall.h> to userspace
  arch/tile: warn and retry if an IPI is not accepted by the target cpu
  arch/tile: stop disabling INTCTRL_1 interrupts during hypervisor downcalls
  arch/tile: fix __ndelay etc to work better
  arch/tile: bug fix: exec'ed task thought it was still single-stepping
  ...

Fix up trivial conflict in arch/tile/kernel/vmlinux.lds.S (percpu
alignment vs section naming convention fix)

13 files changed, 163 insertions, 154 deletions

diff --git a/arch/tile/kernel/entry.S b/arch/tile/kernel/entry.S
index fd8dc42..431e9ae 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 90e7c44..1a39b7c 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 5eed4a0..fffcfa6 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 128805e..0baa758 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 0d8b9e9..e00d717 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 5ad5e13..658752b2 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 e90eb53..b9cd962 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 f185736..3696b18 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 1eb3b39..84a729e 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 9575b37..a429310 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 0d54106b..dd81713 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 f2e156e..49a605b 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 c6ce378..38f64fa 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) = .;