Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "A bit on the largish side due to a series of fixes for a regression in
  the x86 vector management which was introduced in 4.3.  This work was
  started in December already, but it took some time to fix all corner
  cases and a couple of older bugs in that area which were detected
  while at it

  Aside of that a few platform updates for intel-mid, quark and UV and
  two fixes for in the mm code:
   - Use proper types for pgprot values to avoid truncation
   - Prevent a size truncation in the pageattr code when setting page
     attributes for large mappings"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
  x86/mm/pat: Avoid truncation when converting cpa->numpages to address
  x86/mm: Fix types used in pgprot cacheability flags translations
  x86/platform/quark: Print boundaries correctly
  x86/platform/UV: Remove EFI memmap quirk for UV2+
  x86/platform/intel-mid: Join string and fix SoC name
  x86/platform/intel-mid: Enable 64-bit build
  x86/irq: Plug vector cleanup race
  x86/irq: Call irq_force_move_complete with irq descriptor
  x86/irq: Remove outgoing CPU from vector cleanup mask
  x86/irq: Remove the cpumask allocation from send_cleanup_vector()
  x86/irq: Clear move_in_progress before sending cleanup IPI
  x86/irq: Remove offline cpus from vector cleanup
  x86/irq: Get rid of code duplication
  x86/irq: Copy vectormask instead of an AND operation
  x86/irq: Check vector allocation early
  x86/irq: Reorganize the search in assign_irq_vector
  x86/irq: Reorganize the return path in assign_irq_vector
  x86/irq: Do not use apic_chip_data.old_domain as temporary buffer
  x86/irq: Validate that irq descriptor is still active
  x86/irq: Fix a race in x86_vector_free_irqs()
  ...

12 files changed, 209 insertions, 103 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 330e738..9af2e63 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -509,11 +509,10 @@ config X86_INTEL_CE
 
 config X86_INTEL_MID
 	bool "Intel MID platform support"
-	depends on X86_32
 	depends on X86_EXTENDED_PLATFORM
 	depends on X86_PLATFORM_DEVICES
 	depends on PCI
-	depends on PCI_GOANY
+	depends on X86_64 || (PCI_GOANY && X86_32)
 	depends on X86_IO_APIC
 	select SFI
 	select I2C
diff --git a/arch/x86/include/asm/irq.h b/arch/x86/include/asm/irq.h
index 881b476..e7de5c9 100644
--- a/arch/x86/include/asm/irq.h
+++ b/arch/x86/include/asm/irq.h
@@ -23,11 +23,13 @@ extern void irq_ctx_init(int cpu);
 
 #define __ARCH_HAS_DO_SOFTIRQ
 
+struct irq_desc;
+
 #ifdef CONFIG_HOTPLUG_CPU
 #include <linux/cpumask.h>
 extern int check_irq_vectors_for_cpu_disable(void);
 extern void fixup_irqs(void);
-extern void irq_force_complete_move(int);
+extern void irq_force_complete_move(struct irq_desc *desc);
 #endif
 
 #ifdef CONFIG_HAVE_KVM
@@ -37,7 +39,6 @@ extern void kvm_set_posted_intr_wakeup_handler(void (*handler)(void));
 extern void (*x86_platform_ipi_callback)(void);
 extern void native_init_IRQ(void);
 
-struct irq_desc;
 extern bool handle_irq(struct irq_desc *desc, struct pt_regs *regs);
 
 extern __visible unsigned int do_IRQ(struct pt_regs *regs);
diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h
index 04c27a0..4432ab7 100644
--- a/arch/x86/include/asm/pgtable_types.h
+++ b/arch/x86/include/asm/pgtable_types.h
@@ -366,20 +366,18 @@ static inline enum page_cache_mode pgprot2cachemode(pgprot_t pgprot)
 }
 static inline pgprot_t pgprot_4k_2_large(pgprot_t pgprot)
 {
+	pgprotval_t val = pgprot_val(pgprot);
 	pgprot_t new;
-	unsigned long val;
 
-	val = pgprot_val(pgprot);
 	pgprot_val(new) = (val & ~(_PAGE_PAT | _PAGE_PAT_LARGE)) |
 		((val & _PAGE_PAT) << (_PAGE_BIT_PAT_LARGE - _PAGE_BIT_PAT));
 	return new;
 }
 static inline pgprot_t pgprot_large_2_4k(pgprot_t pgprot)
 {
+	pgprotval_t val = pgprot_val(pgprot);
 	pgprot_t new;
-	unsigned long val;
 
-	val = pgprot_val(pgprot);
 	pgprot_val(new) = (val & ~(_PAGE_PAT | _PAGE_PAT_LARGE)) |
 			  ((val & _PAGE_PAT_LARGE) >>
 			   (_PAGE_BIT_PAT_LARGE - _PAGE_BIT_PAT));
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index f253218..fdb0fbf 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2521,6 +2521,7 @@ void __init setup_ioapic_dest(void)
 {
 	int pin, ioapic, irq, irq_entry;
 	const struct cpumask *mask;
+	struct irq_desc *desc;
 	struct irq_data *idata;
 	struct irq_chip *chip;
 
@@ -2536,7 +2537,9 @@ void __init setup_ioapic_dest(void)
 		if (irq < 0 || !mp_init_irq_at_boot(ioapic, irq))
 			continue;
 
-		idata = irq_get_irq_data(irq);
+		desc = irq_to_desc(irq);
+		raw_spin_lock_irq(&desc->lock);
+		idata = irq_desc_get_irq_data(desc);
 
 		/*
 		 * Honour affinities which have been set in early boot
@@ -2550,6 +2553,7 @@ void __init setup_ioapic_dest(void)
 		/* Might be lapic_chip for irq 0 */
 		if (chip->irq_set_affinity)
 			chip->irq_set_affinity(idata, mask, false);
+		raw_spin_unlock_irq(&desc->lock);
 	}
 }
 #endif
diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
index 908cb37..3b670df 100644
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -31,7 +31,7 @@ struct apic_chip_data {
 struct irq_domain *x86_vector_domain;
 EXPORT_SYMBOL_GPL(x86_vector_domain);
 static DEFINE_RAW_SPINLOCK(vector_lock);
-static cpumask_var_t vector_cpumask;
+static cpumask_var_t vector_cpumask, vector_searchmask, searched_cpumask;
 static struct irq_chip lapic_controller;
 #ifdef	CONFIG_X86_IO_APIC
 static struct apic_chip_data *legacy_irq_data[NR_IRQS_LEGACY];
@@ -118,35 +118,47 @@ static int __assign_irq_vector(int irq, struct apic_chip_data *d,
 	 */
 	static int current_vector = FIRST_EXTERNAL_VECTOR + VECTOR_OFFSET_START;
 	static int current_offset = VECTOR_OFFSET_START % 16;
-	int cpu, err;
+	int cpu, vector;
 
-	if (d->move_in_progress)
+	/*
+	 * If there is still a move in progress or the previous move has not
+	 * been cleaned up completely, tell the caller to come back later.
+	 */
+	if (d->move_in_progress ||
+	    cpumask_intersects(d->old_domain, cpu_online_mask))
 		return -EBUSY;
 
 	/* Only try and allocate irqs on cpus that are present */
-	err = -ENOSPC;
 	cpumask_clear(d->old_domain);
+	cpumask_clear(searched_cpumask);
 	cpu = cpumask_first_and(mask, cpu_online_mask);
 	while (cpu < nr_cpu_ids) {
-		int new_cpu, vector, offset;
+		int new_cpu, offset;
 
+		/* Get the possible target cpus for @mask/@cpu from the apic */
 		apic->vector_allocation_domain(cpu, vector_cpumask, mask);
 
+		/*
+		 * Clear the offline cpus from @vector_cpumask for searching
+		 * and verify whether the result overlaps with @mask. If true,
+		 * then the call to apic->cpu_mask_to_apicid_and() will
+		 * succeed as well. If not, no point in trying to find a
+		 * vector in this mask.
+		 */
+		cpumask_and(vector_searchmask, vector_cpumask, cpu_online_mask);
+		if (!cpumask_intersects(vector_searchmask, mask))
+			goto next_cpu;
+
 		if (cpumask_subset(vector_cpumask, d->domain)) {
-			err = 0;
 			if (cpumask_equal(vector_cpumask, d->domain))
-				break;
+				goto success;
 			/*
-			 * New cpumask using the vector is a proper subset of
-			 * the current in use mask. So cleanup the vector
-			 * allocation for the members that are not used anymore.
+			 * Mark the cpus which are not longer in the mask for
+			 * cleanup.
 			 */
-			cpumask_andnot(d->old_domain, d->domain,
-				       vector_cpumask);
-			d->move_in_progress =
-			   cpumask_intersects(d->old_domain, cpu_online_mask);
-			cpumask_and(d->domain, d->domain, vector_cpumask);
-			break;
+			cpumask_andnot(d->old_domain, d->domain, vector_cpumask);
+			vector = d->cfg.vector;
+			goto update;
 		}
 
 		vector = current_vector;
@@ -158,45 +170,60 @@ next:
 			vector = FIRST_EXTERNAL_VECTOR + offset;
 		}
 
-		if (unlikely(current_vector == vector)) {
-			cpumask_or(d->old_domain, d->old_domain,
-				   vector_cpumask);
-			cpumask_andnot(vector_cpumask, mask, d->old_domain);
-			cpu = cpumask_first_and(vector_cpumask,
-						cpu_online_mask);
-			continue;
-		}
+		/* If the search wrapped around, try the next cpu */
+		if (unlikely(current_vector == vector))
+			goto next_cpu;
 
 		if (test_bit(vector, used_vectors))
 			goto next;
 
-		for_each_cpu_and(new_cpu, vector_cpumask, cpu_online_mask) {
+		for_each_cpu(new_cpu, vector_searchmask) {
 			if (!IS_ERR_OR_NULL(per_cpu(vector_irq, new_cpu)[vector]))
 				goto next;
 		}
 		/* Found one! */
 		current_vector = vector;
 		current_offset = offset;
-		if (d->cfg.vector) {
+		/* Schedule the old vector for cleanup on all cpus */
+		if (d->cfg.vector)
 			cpumask_copy(d->old_domain, d->domain);
-			d->move_in_progress =
-			   cpumask_intersects(d->old_domain, cpu_online_mask);
-		}
-		for_each_cpu_and(new_cpu, vector_cpumask, cpu_online_mask)
+		for_each_cpu(new_cpu, vector_searchmask)
 			per_cpu(vector_irq, new_cpu)[vector] = irq_to_desc(irq);
-		d->cfg.vector = vector;
-		cpumask_copy(d->domain, vector_cpumask);
-		err = 0;
-		break;
-	}
+		goto update;
 
-	if (!err) {
-		/* cache destination APIC IDs into cfg->dest_apicid */
-		err = apic->cpu_mask_to_apicid_and(mask, d->domain,
-						   &d->cfg.dest_apicid);
+next_cpu:
+		/*
+		 * We exclude the current @vector_cpumask from the requested
+		 * @mask and try again with the next online cpu in the
+		 * result. We cannot modify @mask, so we use @vector_cpumask
+		 * as a temporary buffer here as it will be reassigned when
+		 * calling apic->vector_allocation_domain() above.
+		 */
+		cpumask_or(searched_cpumask, searched_cpumask, vector_cpumask);
+		cpumask_andnot(vector_cpumask, mask, searched_cpumask);
+		cpu = cpumask_first_and(vector_cpumask, cpu_online_mask);
+		continue;
 	}
+	return -ENOSPC;
 
-	return err;
+update:
+	/*
+	 * Exclude offline cpus from the cleanup mask and set the
+	 * move_in_progress flag when the result is not empty.
+	 */
+	cpumask_and(d->old_domain, d->old_domain, cpu_online_mask);
+	d->move_in_progress = !cpumask_empty(d->old_domain);
+	d->cfg.vector = vector;
+	cpumask_copy(d->domain, vector_cpumask);
+success:
+	/*
+	 * Cache destination APIC IDs into cfg->dest_apicid. This cannot fail
+	 * as we already established, that mask & d->domain & cpu_online_mask
+	 * is not empty.
+	 */
+	BUG_ON(apic->cpu_mask_to_apicid_and(mask, d->domain,
+					    &d->cfg.dest_apicid));
+	return 0;
 }
 
 static int assign_irq_vector(int irq, struct apic_chip_data *data,
@@ -226,10 +253,8 @@ static int assign_irq_vector_policy(int irq, int node,
 static void clear_irq_vector(int irq, struct apic_chip_data *data)
 {
 	struct irq_desc *desc;
-	unsigned long flags;
 	int cpu, vector;
 
-	raw_spin_lock_irqsave(&vector_lock, flags);
 	BUG_ON(!data->cfg.vector);
 
 	vector = data->cfg.vector;
@@ -239,10 +264,13 @@ static void clear_irq_vector(int irq, struct apic_chip_data *data)
 	data->cfg.vector = 0;
 	cpumask_clear(data->domain);
 
-	if (likely(!data->move_in_progress)) {
-		raw_spin_unlock_irqrestore(&vector_lock, flags);
+	/*
+	 * If move is in progress or the old_domain mask is not empty,
+	 * i.e. the cleanup IPI has not been processed yet, we need to remove
+	 * the old references to desc from all cpus vector tables.
+	 */
+	if (!data->move_in_progress && cpumask_empty(data->old_domain))
 		return;
-	}
 
 	desc = irq_to_desc(irq);
 	for_each_cpu_and(cpu, data->old_domain, cpu_online_mask) {
@@ -255,7 +283,6 @@ static void clear_irq_vector(int irq, struct apic_chip_data *data)
 		}
 	}
 	data->move_in_progress = 0;
-	raw_spin_unlock_irqrestore(&vector_lock, flags);
 }
 
 void init_irq_alloc_info(struct irq_alloc_info *info,
@@ -276,19 +303,24 @@ void copy_irq_alloc_info(struct irq_alloc_info *dst, struct irq_alloc_info *src)
 static void x86_vector_free_irqs(struct irq_domain *domain,
 				 unsigned int virq, unsigned int nr_irqs)
 {
+	struct apic_chip_data *apic_data;
 	struct irq_data *irq_data;
+	unsigned long flags;
 	int i;
 
 	for (i = 0; i < nr_irqs; i++) {
 		irq_data = irq_domain_get_irq_data(x86_vector_domain, virq + i);
 		if (irq_data && irq_data->chip_data) {
+			raw_spin_lock_irqsave(&vector_lock, flags);
 			clear_irq_vector(virq + i, irq_data->chip_data);
-			free_apic_chip_data(irq_data->chip_data);
+			apic_data = irq_data->chip_data;
+			irq_domain_reset_irq_data(irq_data);
+			raw_spin_unlock_irqrestore(&vector_lock, flags);
+			free_apic_chip_data(apic_data);
 #ifdef	CONFIG_X86_IO_APIC
 			if (virq + i < nr_legacy_irqs())
 				legacy_irq_data[virq + i] = NULL;
 #endif
-			irq_domain_reset_irq_data(irq_data);
 		}
 	}
 }
@@ -406,6 +438,8 @@ int __init arch_early_irq_init(void)
 	arch_init_htirq_domain(x86_vector_domain);
 
 	BUG_ON(!alloc_cpumask_var(&vector_cpumask, GFP_KERNEL));
+	BUG_ON(!alloc_cpumask_var(&vector_searchmask, GFP_KERNEL));
+	BUG_ON(!alloc_cpumask_var(&searched_cpumask, GFP_KERNEL));
 
 	return arch_early_ioapic_init();
 }
@@ -494,14 +528,7 @@ static int apic_set_affinity(struct irq_data *irq_data,
 		return -EINVAL;
 
 	err = assign_irq_vector(irq, data, dest);
-	if (err) {
-		if (assign_irq_vector(irq, data,
-				      irq_data_get_affinity_mask(irq_data)))
-			pr_err("Failed to recover vector for irq %d\n", irq);
-		return err;
-	}
-
-	return IRQ_SET_MASK_OK;
+	return err ? err : IRQ_SET_MASK_OK;
 }
 
 static struct irq_chip lapic_controller = {
@@ -513,20 +540,12 @@ static struct irq_chip lapic_controller = {
 #ifdef CONFIG_SMP
 static void __send_cleanup_vector(struct apic_chip_data *data)
 {
-	cpumask_var_t cleanup_mask;
-
-	if (unlikely(!alloc_cpumask_var(&cleanup_mask, GFP_ATOMIC))) {
-		unsigned int i;
-
-		for_each_cpu_and(i, data->old_domain, cpu_online_mask)
-			apic->send_IPI_mask(cpumask_of(i),
-					    IRQ_MOVE_CLEANUP_VECTOR);
-	} else {
-		cpumask_and(cleanup_mask, data->old_domain, cpu_online_mask);
-		apic->send_IPI_mask(cleanup_mask, IRQ_MOVE_CLEANUP_VECTOR);
-		free_cpumask_var(cleanup_mask);
-	}
+	raw_spin_lock(&vector_lock);
+	cpumask_and(data->old_domain, data->old_domain, cpu_online_mask);
 	data->move_in_progress = 0;
+	if (!cpumask_empty(data->old_domain))
+		apic->send_IPI_mask(data->old_domain, IRQ_MOVE_CLEANUP_VECTOR);
+	raw_spin_unlock(&vector_lock);
 }
 
 void send_cleanup_vector(struct irq_cfg *cfg)
@@ -570,12 +589,25 @@ asmlinkage __visible void smp_irq_move_cleanup_interrupt(void)
 			goto unlock;
 
 		/*
-		 * Check if the irq migration is in progress. If so, we
-		 * haven't received the cleanup request yet for this irq.
+		 * Nothing to cleanup if irq migration is in progress
+		 * or this cpu is not set in the cleanup mask.
 		 */
-		if (data->move_in_progress)
+		if (data->move_in_progress ||
+		    !cpumask_test_cpu(me, data->old_domain))
 			goto unlock;
 
+		/*
+		 * We have two cases to handle here:
+		 * 1) vector is unchanged but the target mask got reduced
+		 * 2) vector and the target mask has changed
+		 *
+		 * #1 is obvious, but in #2 we have two vectors with the same
+		 * irq descriptor: the old and the new vector. So we need to
+		 * make sure that we only cleanup the old vector. The new
+		 * vector has the current @vector number in the config and
+		 * this cpu is part of the target mask. We better leave that
+		 * one alone.
+		 */
 		if (vector == data->cfg.vector &&
 		    cpumask_test_cpu(me, data->domain))
 			goto unlock;
@@ -593,6 +625,7 @@ asmlinkage __visible void smp_irq_move_cleanup_interrupt(void)
 			goto unlock;
 		}
 		__this_cpu_write(vector_irq[vector], VECTOR_UNUSED);
+		cpumask_clear_cpu(me, data->old_domain);
 unlock:
 		raw_spin_unlock(&desc->lock);
 	}
@@ -621,12 +654,48 @@ void irq_complete_move(struct irq_cfg *cfg)
 	__irq_complete_move(cfg, ~get_irq_regs()->orig_ax);
 }
 
-void irq_force_complete_move(int irq)
+/*
+ * Called with @desc->lock held and interrupts disabled.
+ */
+void irq_force_complete_move(struct irq_desc *desc)
 {
-	struct irq_cfg *cfg = irq_cfg(irq);
+	struct irq_data *irqdata = irq_desc_get_irq_data(desc);
+	struct apic_chip_data *data = apic_chip_data(irqdata);
+	struct irq_cfg *cfg = data ? &data->cfg : NULL;
 
-	if (cfg)
-		__irq_complete_move(cfg, cfg->vector);
+	if (!cfg)
+		return;
+
+	__irq_complete_move(cfg, cfg->vector);
+
+	/*
+	 * This is tricky. If the cleanup of @data->old_domain has not been
+	 * done yet, then the following setaffinity call will fail with
+	 * -EBUSY. This can leave the interrupt in a stale state.
+	 *
+	 * The cleanup cannot make progress because we hold @desc->lock. So in
+	 * case @data->old_domain is not yet cleaned up, we need to drop the
+	 * lock and acquire it again. @desc cannot go away, because the
+	 * hotplug code holds the sparse irq lock.
+	 */
+	raw_spin_lock(&vector_lock);
+	/* Clean out all offline cpus (including ourself) first. */
+	cpumask_and(data->old_domain, data->old_domain, cpu_online_mask);
+	while (!cpumask_empty(data->old_domain)) {
+		raw_spin_unlock(&vector_lock);
+		raw_spin_unlock(&desc->lock);
+		cpu_relax();
+		raw_spin_lock(&desc->lock);
+		/*
+		 * Reevaluate apic_chip_data. It might have been cleared after
+		 * we dropped @desc->lock.
+		 */
+		data = apic_chip_data(irqdata);
+		if (!data)
+			return;
+		raw_spin_lock(&vector_lock);
+	}
+	raw_spin_unlock(&vector_lock);
 }
 #endif
 
diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index d760c6b..624db005 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -889,7 +889,10 @@ void __init uv_system_init(void)
 		return;
 	}
 	pr_info("UV: Found %s hub\n", hub);
-	map_low_mmrs();
+
+	/* We now only need to map the MMRs on UV1 */
+	if (is_uv1_hub())
+		map_low_mmrs();
 
 	m_n_config.v = uv_read_local_mmr(UVH_RH_GAM_CONFIG_MMR );
 	m_val = m_n_config.s.m_skt;
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index f129a9a..2c0f340 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -192,5 +192,13 @@ void __init x86_64_start_reservations(char *real_mode_data)
 
 	reserve_ebda_region();
 
+	switch (boot_params.hdr.hardware_subarch) {
+	case X86_SUBARCH_INTEL_MID:
+		x86_intel_mid_early_setup();
+		break;
+	default:
+		break;
+	}
+
 	start_kernel();
 }
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index f8062aa..61521dc 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -462,7 +462,7 @@ void fixup_irqs(void)
 		 * non intr-remapping case, we can't wait till this interrupt
 		 * arrives at this cpu before completing the irq move.
 		 */
-		irq_force_complete_move(irq);
+		irq_force_complete_move(desc);
 
 		if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) {
 			break_affinity = 1;
@@ -470,6 +470,15 @@ void fixup_irqs(void)
 		}
 
 		chip = irq_data_get_irq_chip(data);
+		/*
+		 * The interrupt descriptor might have been cleaned up
+		 * already, but it is not yet removed from the radix tree
+		 */
+		if (!chip) {
+			raw_spin_unlock(&desc->lock);
+			continue;
+		}
+
 		if (!irqd_can_move_in_process_context(data) && chip->irq_mask)
 			chip->irq_mask(data);
 
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index fc6a4c8..2440814 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -33,7 +33,7 @@ struct cpa_data {
 	pgd_t		*pgd;
 	pgprot_t	mask_set;
 	pgprot_t	mask_clr;
-	int		numpages;
+	unsigned long	numpages;
 	int		flags;
 	unsigned long	pfn;
 	unsigned	force_split : 1;
@@ -1350,7 +1350,7 @@ static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias)
 		 * CPA operation. Either a large page has been
 		 * preserved or a single page update happened.
 		 */
-		BUG_ON(cpa->numpages > numpages);
+		BUG_ON(cpa->numpages > numpages || !cpa->numpages);
 		numpages -= cpa->numpages;
 		if (cpa->flags & (CPA_PAGES_ARRAY | CPA_ARRAY))
 			cpa->curpage++;
diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c
index 1c7380d..2d66db8 100644
--- a/arch/x86/platform/efi/quirks.c
+++ b/arch/x86/platform/efi/quirks.c
@@ -8,6 +8,7 @@
 #include <linux/memblock.h>
 #include <linux/bootmem.h>
 #include <linux/acpi.h>
+#include <linux/dmi.h>
 #include <asm/efi.h>
 #include <asm/uv/uv.h>
 
@@ -248,6 +249,16 @@ out:
 	return ret;
 }
 
+static const struct dmi_system_id sgi_uv1_dmi[] = {
+	{ NULL, "SGI UV1",
+		{	DMI_MATCH(DMI_PRODUCT_NAME,	"Stoutland Platform"),
+			DMI_MATCH(DMI_PRODUCT_VERSION,	"1.0"),
+			DMI_MATCH(DMI_BIOS_VENDOR,	"SGI.COM"),
+		}
+	},
+	{ } /* NULL entry stops DMI scanning */
+};
+
 void __init efi_apply_memmap_quirks(void)
 {
 	/*
@@ -260,10 +271,8 @@ void __init efi_apply_memmap_quirks(void)
 		efi_unmap_memmap();
 	}
 
-	/*
-	 * UV doesn't support the new EFI pagetable mapping yet.
-	 */
-	if (is_uv_system())
+	/* UV2+ BIOS has a fix for this issue.  UV1 still needs the quirk. */
+	if (dmi_check_system(sgi_uv1_dmi))
 		set_bit(EFI_OLD_MEMMAP, &efi.flags);
 }
 
diff --git a/arch/x86/platform/intel-mid/intel-mid.c b/arch/x86/platform/intel-mid/intel-mid.c
index 1bbc21e..90bb997 100644
--- a/arch/x86/platform/intel-mid/intel-mid.c
+++ b/arch/x86/platform/intel-mid/intel-mid.c
@@ -138,7 +138,7 @@ static void intel_mid_arch_setup(void)
 		intel_mid_ops = get_intel_mid_ops[__intel_mid_cpu_chip]();
 	else {
 		intel_mid_ops = get_intel_mid_ops[INTEL_MID_CPU_CHIP_PENWELL]();
-		pr_info("ARCH: Unknown SoC, assuming PENWELL!\n");
+		pr_info("ARCH: Unknown SoC, assuming Penwell!\n");
 	}
 
 out:
@@ -214,12 +214,10 @@ static inline int __init setup_x86_intel_mid_timer(char *arg)
 	else if (strcmp("lapic_and_apbt", arg) == 0)
 		intel_mid_timer_options = INTEL_MID_TIMER_LAPIC_APBT;
 	else {
-		pr_warn("X86 INTEL_MID timer option %s not recognised"
-			   " use x86_intel_mid_timer=apbt_only or lapic_and_apbt\n",
-			   arg);
+		pr_warn("X86 INTEL_MID timer option %s not recognised use x86_intel_mid_timer=apbt_only or lapic_and_apbt\n",
+			arg);
 		return -EINVAL;
 	}
 	return 0;
 }
 __setup("x86_intel_mid_timer=", setup_x86_intel_mid_timer);
-
diff --git a/arch/x86/platform/intel-quark/imr.c b/arch/x86/platform/intel-quark/imr.c
index c1bdafa..c61b6c3 100644
--- a/arch/x86/platform/intel-quark/imr.c
+++ b/arch/x86/platform/intel-quark/imr.c
@@ -220,11 +220,12 @@ static int imr_dbgfs_state_show(struct seq_file *s, void *unused)
 		if (imr_is_enabled(&imr)) {
 			base = imr_to_phys(imr.addr_lo);
 			end = imr_to_phys(imr.addr_hi) + IMR_MASK;
+			size = end - base + 1;
 		} else {
 			base = 0;
 			end = 0;
+			size = 0;
 		}
-		size = end - base;
 		seq_printf(s, "imr%02i: base=%pa, end=%pa, size=0x%08zx "
 			   "rmask=0x%08x, wmask=0x%08x, %s, %s\n", i,
 			   &base, &end, size, imr.rmask, imr.wmask,
@@ -579,6 +580,7 @@ static void __init imr_fixup_memmap(struct imr_device *idev)
 {
 	phys_addr_t base = virt_to_phys(&_text);
 	size_t size = virt_to_phys(&__end_rodata) - base;
+	unsigned long start, end;
 	int i;
 	int ret;
 
@@ -586,18 +588,24 @@ static void __init imr_fixup_memmap(struct imr_device *idev)
 	for (i = 0; i < idev->max_imr; i++)
 		imr_clear(i);
 
+	start = (unsigned long)_text;
+	end = (unsigned long)__end_rodata - 1;
+
 	/*
 	 * Setup a locked IMR around the physical extent of the kernel
 	 * from the beginning of the .text secton to the end of the
 	 * .rodata section as one physically contiguous block.
+	 *
+	 * We don't round up @size since it is already PAGE_SIZE aligned.
+	 * See vmlinux.lds.S for details.
 	 */
 	ret = imr_add_range(base, size, IMR_CPU, IMR_CPU, true);
 	if (ret < 0) {
-		pr_err("unable to setup IMR for kernel: (%p - %p)\n",
-			&_text, &__end_rodata);
+		pr_err("unable to setup IMR for kernel: %zu KiB (%lx - %lx)\n",
+			size / 1024, start, end);
 	} else {
-		pr_info("protecting kernel .text - .rodata: %zu KiB (%p - %p)\n",
-			size / 1024, &_text, &__end_rodata);
+		pr_info("protecting kernel .text - .rodata: %zu KiB (%lx - %lx)\n",
+			size / 1024, start, end);
 	}
 
 }