Merge branch 'akpm' (patches from Andrew)

Merge yet more updates from Andrew Morton:

 - lots of little subsystems

 - a few post-linux-next MM material. Most of the rest awaits more
   merging of other trees.

Subsystems affected by this series: alpha, procfs, misc, core-kernel,
bitmap, lib, lz4, checkpatch, nilfs, kdump, rapidio, gcov, bfs, relay,
resource, ubsan, reboot, fault-injection, lzo, apparmor, and mm (swap,
memory-hotplug, pagemap, cleanups, and gup).

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (86 commits)
  mm: fix some spelling mistakes in comments
  mm: simplify follow_pte{,pmd}
  mm: unexport follow_pte_pmd
  apparmor: remove duplicate macro list_entry_is_head()
  lib/lzo/lzo1x_compress.c: make lzogeneric1x_1_compress() static
  fault-injection: handle EI_ETYPE_TRUE
  reboot: hide from sysfs not applicable settings
  reboot: allow to override reboot type if quirks are found
  reboot: remove cf9_safe from allowed types and rename cf9_force
  reboot: allow to specify reboot mode via sysfs
  reboot: refactor and comment the cpu selection code
  lib/ubsan.c: mark type_check_kinds with static keyword
  kcov: don't instrument with UBSAN
  ubsan: expand tests and reporting
  ubsan: remove UBSAN_MISC in favor of individual options
  ubsan: enable for all*config builds
  ubsan: disable UBSAN_TRAP for all*config
  ubsan: disable object-size sanitizer under GCC
  ubsan: move cc-option tests into Kconfig
  ubsan: remove redundant -Wno-maybe-uninitialized
  ...

9 files changed, 271 insertions, 135 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index dddf51266719..aa7368c7eabf 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -34,8 +34,11 @@ KCOV_INSTRUMENT_extable.o := n
 KCOV_INSTRUMENT_stacktrace.o := n
 # Don't self-instrument.
 KCOV_INSTRUMENT_kcov.o := n
+# If sanitizers detect any issues in kcov, it may lead to recursion
+# via printk, etc.
 KASAN_SANITIZE_kcov.o := n
 KCSAN_SANITIZE_kcov.o := n
+UBSAN_SANITIZE_kcov.o := n
 CFLAGS_kcov.o := $(call cc-option, -fno-conserve-stack) -fno-stack-protector
 
 obj-y += sched/
diff --git a/kernel/acct.c b/kernel/acct.c
index f175df8f6aa4..a64102be2bb0 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -381,9 +381,7 @@ static comp2_t encode_comp2_t(u64 value)
 		return (value & (MAXFRACT2>>1)) | (exp << (MANTSIZE2-1));
 	}
 }
-#endif
-
-#if ACCT_VERSION == 3
+#elif ACCT_VERSION == 3
 /*
  * encode an u64 into a 32 bit IEEE float
  */
@@ -500,8 +498,7 @@ static void do_acct_process(struct bsd_acct_struct *acct)
 	/* backward-compatible 16 bit fields */
 	ac.ac_uid16 = ac.ac_uid;
 	ac.ac_gid16 = ac.ac_gid;
-#endif
-#if ACCT_VERSION == 3
+#elif ACCT_VERSION == 3
 	{
 		struct pid_namespace *ns = acct->ns;
 
diff --git a/kernel/crash_core.c b/kernel/crash_core.c
index 4fcfe0b70c4e..825284baaf46 100644
--- a/kernel/crash_core.c
+++ b/kernel/crash_core.c
@@ -447,6 +447,7 @@ static int __init crash_save_vmcoreinfo_init(void)
 	VMCOREINFO_PAGESIZE(PAGE_SIZE);
 
 	VMCOREINFO_SYMBOL(init_uts_ns);
+	VMCOREINFO_OFFSET(uts_namespace, name);
 	VMCOREINFO_SYMBOL(node_online_map);
 #ifdef CONFIG_MMU
 	VMCOREINFO_SYMBOL_ARRAY(swapper_pg_dir);
diff --git a/kernel/fail_function.c b/kernel/fail_function.c
index b0b1ad93fa95..60dc825ecc2b 100644
--- a/kernel/fail_function.c
+++ b/kernel/fail_function.c
@@ -37,9 +37,7 @@ static unsigned long adjust_error_retval(unsigned long addr, unsigned long retv)
 {
 	switch (get_injectable_error_type(addr)) {
 	case EI_ETYPE_NULL:
-		if (retv != 0)
-			return 0;
-		break;
+		return 0;
 	case EI_ETYPE_ERRNO:
 		if (retv < (unsigned long)-MAX_ERRNO)
 			return (unsigned long)-EINVAL;
@@ -48,6 +46,8 @@ static unsigned long adjust_error_retval(unsigned long addr, unsigned long retv)
 		if (retv != 0 && retv < (unsigned long)-MAX_ERRNO)
 			return (unsigned long)-EINVAL;
 		break;
+	case EI_ETYPE_TRUE:
+		return 1;
 	}
 
 	return retv;
diff --git a/kernel/gcov/gcc_4_7.c b/kernel/gcov/gcc_4_7.c
index 53c67c87f141..c53408a00d0b 100644
--- a/kernel/gcov/gcc_4_7.c
+++ b/kernel/gcov/gcc_4_7.c
@@ -25,10 +25,8 @@
 #define GCOV_COUNTERS			9
 #elif (__GNUC__ > 5) || (__GNUC__ == 5 && __GNUC_MINOR__ >= 1)
 #define GCOV_COUNTERS			10
-#elif __GNUC__ == 4 && __GNUC_MINOR__ >= 9
-#define GCOV_COUNTERS			9
 #else
-#define GCOV_COUNTERS			8
+#define GCOV_COUNTERS			9
 #endif
 
 #define GCOV_TAG_FUNCTION_LENGTH	3
@@ -229,10 +227,10 @@ int gcov_info_is_compatible(struct gcov_info *info1, struct gcov_info *info2)
 
 /**
  * gcov_info_add - add up profiling data
- * @dest: profiling data set to which data is added
- * @source: profiling data set which is added
+ * @dst: profiling data set to which data is added
+ * @src: profiling data set which is added
  *
- * Adds profiling counts of @source to @dest.
+ * Adds profiling counts of @src to @dst.
  */
 void gcov_info_add(struct gcov_info *dst, struct gcov_info *src)
 {
diff --git a/kernel/reboot.c b/kernel/reboot.c
index 2a18b76ffc06..eb1b15850761 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -553,20 +553,24 @@ static int __init reboot_setup(char *str)
 			break;
 
 		case 's':
-			if (isdigit(*(str+1)))
-				reboot_cpu = simple_strtoul(str+1, NULL, 0);
-			else if (str[1] == 'm' && str[2] == 'p' &&
-							isdigit(*(str+3)))
-				reboot_cpu = simple_strtoul(str+3, NULL, 0);
-			else
+			/*
+			 * reboot_cpu is s[mp]#### with #### being the processor
+			 * to be used for rebooting. Skip 's' or 'smp' prefix.
+			 */
+			str += str[1] == 'm' && str[2] == 'p' ? 3 : 1;
+
+			if (isdigit(str[0])) {
+				int cpu = simple_strtoul(str, NULL, 0);
+
+				if (cpu >= num_possible_cpus()) {
+					pr_err("Ignoring the CPU number in reboot= option. "
+					"CPU %d exceeds possible cpu number %d\n",
+					cpu, num_possible_cpus());
+					break;
+				}
+				reboot_cpu = cpu;
+			} else
 				*mode = REBOOT_SOFT;
-			if (reboot_cpu >= num_possible_cpus()) {
-				pr_err("Ignoring the CPU number in reboot= option. "
-				       "CPU %d exceeds possible cpu number %d\n",
-				       reboot_cpu, num_possible_cpus());
-				reboot_cpu = 0;
-				break;
-			}
 			break;
 
 		case 'g':
@@ -596,3 +600,217 @@ static int __init reboot_setup(char *str)
 	return 1;
 }
 __setup("reboot=", reboot_setup);
+
+#ifdef CONFIG_SYSFS
+
+#define REBOOT_COLD_STR		"cold"
+#define REBOOT_WARM_STR		"warm"
+#define REBOOT_HARD_STR		"hard"
+#define REBOOT_SOFT_STR		"soft"
+#define REBOOT_GPIO_STR		"gpio"
+#define REBOOT_UNDEFINED_STR	"undefined"
+
+#define BOOT_TRIPLE_STR		"triple"
+#define BOOT_KBD_STR		"kbd"
+#define BOOT_BIOS_STR		"bios"
+#define BOOT_ACPI_STR		"acpi"
+#define BOOT_EFI_STR		"efi"
+#define BOOT_PCI_STR		"pci"
+
+static ssize_t mode_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
+{
+	const char *val;
+
+	switch (reboot_mode) {
+	case REBOOT_COLD:
+		val = REBOOT_COLD_STR;
+		break;
+	case REBOOT_WARM:
+		val = REBOOT_WARM_STR;
+		break;
+	case REBOOT_HARD:
+		val = REBOOT_HARD_STR;
+		break;
+	case REBOOT_SOFT:
+		val = REBOOT_SOFT_STR;
+		break;
+	case REBOOT_GPIO:
+		val = REBOOT_GPIO_STR;
+		break;
+	default:
+		val = REBOOT_UNDEFINED_STR;
+	}
+
+	return sprintf(buf, "%s\n", val);
+}
+static ssize_t mode_store(struct kobject *kobj, struct kobj_attribute *attr,
+			  const char *buf, size_t count)
+{
+	if (!capable(CAP_SYS_BOOT))
+		return -EPERM;
+
+	if (!strncmp(buf, REBOOT_COLD_STR, strlen(REBOOT_COLD_STR)))
+		reboot_mode = REBOOT_COLD;
+	else if (!strncmp(buf, REBOOT_WARM_STR, strlen(REBOOT_WARM_STR)))
+		reboot_mode = REBOOT_WARM;
+	else if (!strncmp(buf, REBOOT_HARD_STR, strlen(REBOOT_HARD_STR)))
+		reboot_mode = REBOOT_HARD;
+	else if (!strncmp(buf, REBOOT_SOFT_STR, strlen(REBOOT_SOFT_STR)))
+		reboot_mode = REBOOT_SOFT;
+	else if (!strncmp(buf, REBOOT_GPIO_STR, strlen(REBOOT_GPIO_STR)))
+		reboot_mode = REBOOT_GPIO;
+	else
+		return -EINVAL;
+
+	reboot_default = 0;
+
+	return count;
+}
+static struct kobj_attribute reboot_mode_attr = __ATTR_RW(mode);
+
+#ifdef CONFIG_X86
+static ssize_t force_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%d\n", reboot_force);
+}
+static ssize_t force_store(struct kobject *kobj, struct kobj_attribute *attr,
+			  const char *buf, size_t count)
+{
+	bool res;
+
+	if (!capable(CAP_SYS_BOOT))
+		return -EPERM;
+
+	if (kstrtobool(buf, &res))
+		return -EINVAL;
+
+	reboot_default = 0;
+	reboot_force = res;
+
+	return count;
+}
+static struct kobj_attribute reboot_force_attr = __ATTR_RW(force);
+
+static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
+{
+	const char *val;
+
+	switch (reboot_type) {
+	case BOOT_TRIPLE:
+		val = BOOT_TRIPLE_STR;
+		break;
+	case BOOT_KBD:
+		val = BOOT_KBD_STR;
+		break;
+	case BOOT_BIOS:
+		val = BOOT_BIOS_STR;
+		break;
+	case BOOT_ACPI:
+		val = BOOT_ACPI_STR;
+		break;
+	case BOOT_EFI:
+		val = BOOT_EFI_STR;
+		break;
+	case BOOT_CF9_FORCE:
+		val = BOOT_PCI_STR;
+		break;
+	default:
+		val = REBOOT_UNDEFINED_STR;
+	}
+
+	return sprintf(buf, "%s\n", val);
+}
+static ssize_t type_store(struct kobject *kobj, struct kobj_attribute *attr,
+			  const char *buf, size_t count)
+{
+	if (!capable(CAP_SYS_BOOT))
+		return -EPERM;
+
+	if (!strncmp(buf, BOOT_TRIPLE_STR, strlen(BOOT_TRIPLE_STR)))
+		reboot_type = BOOT_TRIPLE;
+	else if (!strncmp(buf, BOOT_KBD_STR, strlen(BOOT_KBD_STR)))
+		reboot_type = BOOT_KBD;
+	else if (!strncmp(buf, BOOT_BIOS_STR, strlen(BOOT_BIOS_STR)))
+		reboot_type = BOOT_BIOS;
+	else if (!strncmp(buf, BOOT_ACPI_STR, strlen(BOOT_ACPI_STR)))
+		reboot_type = BOOT_ACPI;
+	else if (!strncmp(buf, BOOT_EFI_STR, strlen(BOOT_EFI_STR)))
+		reboot_type = BOOT_EFI;
+	else if (!strncmp(buf, BOOT_PCI_STR, strlen(BOOT_PCI_STR)))
+		reboot_type = BOOT_CF9_FORCE;
+	else
+		return -EINVAL;
+
+	reboot_default = 0;
+
+	return count;
+}
+static struct kobj_attribute reboot_type_attr = __ATTR_RW(type);
+#endif
+
+#ifdef CONFIG_SMP
+static ssize_t cpu_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%d\n", reboot_cpu);
+}
+static ssize_t cpu_store(struct kobject *kobj, struct kobj_attribute *attr,
+			  const char *buf, size_t count)
+{
+	unsigned int cpunum;
+	int rc;
+
+	if (!capable(CAP_SYS_BOOT))
+		return -EPERM;
+
+	rc = kstrtouint(buf, 0, &cpunum);
+
+	if (rc)
+		return rc;
+
+	if (cpunum >= num_possible_cpus())
+		return -ERANGE;
+
+	reboot_default = 0;
+	reboot_cpu = cpunum;
+
+	return count;
+}
+static struct kobj_attribute reboot_cpu_attr = __ATTR_RW(cpu);
+#endif
+
+static struct attribute *reboot_attrs[] = {
+	&reboot_mode_attr.attr,
+#ifdef CONFIG_X86
+	&reboot_force_attr.attr,
+	&reboot_type_attr.attr,
+#endif
+#ifdef CONFIG_SMP
+	&reboot_cpu_attr.attr,
+#endif
+	NULL,
+};
+
+static const struct attribute_group reboot_attr_group = {
+	.attrs = reboot_attrs,
+};
+
+static int __init reboot_ksysfs_init(void)
+{
+	struct kobject *reboot_kobj;
+	int ret;
+
+	reboot_kobj = kobject_create_and_add("reboot", kernel_kobj);
+	if (!reboot_kobj)
+		return -ENOMEM;
+
+	ret = sysfs_create_group(reboot_kobj, &reboot_attr_group);
+	if (ret) {
+		kobject_put(reboot_kobj);
+		return ret;
+	}
+
+	return 0;
+}
+late_initcall(reboot_ksysfs_init);
+
+#endif
diff --git a/kernel/relay.c b/kernel/relay.c
index b08d936d5fa7..d1a67fbb819d 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -28,15 +28,6 @@ static DEFINE_MUTEX(relay_channels_mutex);
 static LIST_HEAD(relay_channels);
 
 /*
- * close() vm_op implementation for relay file mapping.
- */
-static void relay_file_mmap_close(struct vm_area_struct *vma)
-{
-	struct rchan_buf *buf = vma->vm_private_data;
-	buf->chan->cb->buf_unmapped(buf, vma->vm_file);
-}
-
-/*
  * fault() vm_op implementation for relay file mapping.
  */
 static vm_fault_t relay_buf_fault(struct vm_fault *vmf)
@@ -62,7 +53,6 @@ static vm_fault_t relay_buf_fault(struct vm_fault *vmf)
  */
 static const struct vm_operations_struct relay_file_mmap_ops = {
 	.fault = relay_buf_fault,
-	.close = relay_file_mmap_close,
 };
 
 /*
@@ -96,7 +86,6 @@ static void relay_free_page_array(struct page **array)
 static int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma)
 {
 	unsigned long length = vma->vm_end - vma->vm_start;
-	struct file *filp = vma->vm_file;
 
 	if (!buf)
 		return -EBADF;
@@ -107,7 +96,6 @@ static int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma)
 	vma->vm_ops = &relay_file_mmap_ops;
 	vma->vm_flags |= VM_DONTEXPAND;
 	vma->vm_private_data = buf;
-	buf->chan->cb->buf_mapped(buf, filp);
 
 	return 0;
 }
@@ -264,70 +252,16 @@ EXPORT_SYMBOL_GPL(relay_buf_full);
  * High-level relay kernel API and associated functions.
  */
 
-/*
- * rchan_callback implementations defining default channel behavior.  Used
- * in place of corresponding NULL values in client callback struct.
- */
-
-/*
- * subbuf_start() default callback.  Does nothing.
- */
-static int subbuf_start_default_callback (struct rchan_buf *buf,
-					  void *subbuf,
-					  void *prev_subbuf,
-					  size_t prev_padding)
-{
-	if (relay_buf_full(buf))
-		return 0;
-
-	return 1;
-}
-
-/*
- * buf_mapped() default callback.  Does nothing.
- */
-static void buf_mapped_default_callback(struct rchan_buf *buf,
-					struct file *filp)
-{
-}
-
-/*
- * buf_unmapped() default callback.  Does nothing.
- */
-static void buf_unmapped_default_callback(struct rchan_buf *buf,
-					  struct file *filp)
-{
-}
-
-/*
- * create_buf_file_create() default callback.  Does nothing.
- */
-static struct dentry *create_buf_file_default_callback(const char *filename,
-						       struct dentry *parent,
-						       umode_t mode,
-						       struct rchan_buf *buf,
-						       int *is_global)
+static int relay_subbuf_start(struct rchan_buf *buf, void *subbuf,
+			      void *prev_subbuf, size_t prev_padding)
 {
-	return NULL;
-}
+	if (!buf->chan->cb->subbuf_start)
+		return !relay_buf_full(buf);
 
-/*
- * remove_buf_file() default callback.  Does nothing.
- */
-static int remove_buf_file_default_callback(struct dentry *dentry)
-{
-	return -EINVAL;
+	return buf->chan->cb->subbuf_start(buf, subbuf,
+					   prev_subbuf, prev_padding);
 }
 
-/* relay channel default callbacks */
-static struct rchan_callbacks default_channel_callbacks = {
-	.subbuf_start = subbuf_start_default_callback,
-	.buf_mapped = buf_mapped_default_callback,
-	.buf_unmapped = buf_unmapped_default_callback,
-	.create_buf_file = create_buf_file_default_callback,
-	.remove_buf_file = remove_buf_file_default_callback,
-};
-
 /**
  *	wakeup_readers - wake up readers waiting on a channel
  *	@work: contains the channel buffer
@@ -371,7 +305,7 @@ static void __relay_reset(struct rchan_buf *buf, unsigned int init)
 	for (i = 0; i < buf->chan->n_subbufs; i++)
 		buf->padding[i] = 0;
 
-	buf->chan->cb->subbuf_start(buf, buf->data, NULL, 0);
+	relay_subbuf_start(buf, buf->data, NULL, 0);
 }
 
 /**
@@ -499,27 +433,6 @@ static void relay_close_buf(struct rchan_buf *buf)
 	kref_put(&buf->kref, relay_remove_buf);
 }
 
-static void setup_callbacks(struct rchan *chan,
-				   struct rchan_callbacks *cb)
-{
-	if (!cb) {
-		chan->cb = &default_channel_callbacks;
-		return;
-	}
-
-	if (!cb->subbuf_start)
-		cb->subbuf_start = subbuf_start_default_callback;
-	if (!cb->buf_mapped)
-		cb->buf_mapped = buf_mapped_default_callback;
-	if (!cb->buf_unmapped)
-		cb->buf_unmapped = buf_unmapped_default_callback;
-	if (!cb->create_buf_file)
-		cb->create_buf_file = create_buf_file_default_callback;
-	if (!cb->remove_buf_file)
-		cb->remove_buf_file = remove_buf_file_default_callback;
-	chan->cb = cb;
-}
-
 int relay_prepare_cpu(unsigned int cpu)
 {
 	struct rchan *chan;
@@ -565,7 +478,7 @@ struct rchan *relay_open(const char *base_filename,
 			 struct dentry *parent,
 			 size_t subbuf_size,
 			 size_t n_subbufs,
-			 struct rchan_callbacks *cb,
+			 const struct rchan_callbacks *cb,
 			 void *private_data)
 {
 	unsigned int i;
@@ -576,6 +489,8 @@ struct rchan *relay_open(const char *base_filename,
 		return NULL;
 	if (subbuf_size > UINT_MAX / n_subbufs)
 		return NULL;
+	if (!cb || !cb->create_buf_file || !cb->remove_buf_file)
+		return NULL;
 
 	chan = kzalloc(sizeof(struct rchan), GFP_KERNEL);
 	if (!chan)
@@ -597,7 +512,7 @@ struct rchan *relay_open(const char *base_filename,
 		chan->has_base_filename = 1;
 		strlcpy(chan->base_filename, base_filename, NAME_MAX);
 	}
-	setup_callbacks(chan, cb);
+	chan->cb = cb;
 	kref_init(&chan->kref);
 
 	mutex_lock(&relay_channels_mutex);
@@ -780,7 +695,7 @@ size_t relay_switch_subbuf(struct rchan_buf *buf, size_t length)
 	new_subbuf = buf->subbufs_produced % buf->chan->n_subbufs;
 	new = buf->start + new_subbuf * buf->chan->subbuf_size;
 	buf->offset = 0;
-	if (!buf->chan->cb->subbuf_start(buf, new, old, buf->prev_padding)) {
+	if (!relay_subbuf_start(buf, new, old, buf->prev_padding)) {
 		buf->offset = buf->chan->subbuf_size + 1;
 		return 0;
 	}
diff --git a/kernel/resource.c b/kernel/resource.c
index 82df80417489..833394f9c608 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -320,9 +320,8 @@ int release_resource(struct resource *old)
 EXPORT_SYMBOL(release_resource);
 
 /**
- * Finds the lowest iomem resource that covers part of [@start..@end].  The
- * caller must specify @start, @end, @flags, and @desc (which may be
- * IORES_DESC_NONE).
+ * find_next_iomem_res - Finds the lowest iomem resource that covers part of
+ *			 [@start..@end].
  *
  * If a resource is found, returns 0 and @*res is overwritten with the part
  * of the resource that's within [@start..@end]; if none is found, returns
@@ -337,6 +336,9 @@ EXPORT_SYMBOL(release_resource);
  * @desc:	descriptor the resource must have
  * @first_lvl:	walk only the first level children, if set
  * @res:	return ptr, if resource found
+ *
+ * The caller must specify @start, @end, @flags, and @desc
+ * (which may be IORES_DESC_NONE).
  */
 static int find_next_iomem_res(resource_size_t start, resource_size_t end,
 			       unsigned long flags, unsigned long desc,
@@ -416,11 +418,9 @@ static int __walk_iomem_res_desc(resource_size_t start, resource_size_t end,
 }
 
 /**
- * Walks through iomem resources and calls func() with matching resource
- * ranges. This walks through whole tree and not just first level children.
- * All the memory ranges which overlap start,end and also match flags and
- * desc are valid candidates.
- *
+ * walk_iomem_res_desc - Walks through iomem resources and calls func()
+ *			 with matching resource ranges.
+ * *
  * @desc: I/O resource descriptor. Use IORES_DESC_NONE to skip @desc check.
  * @flags: I/O resource flags
  * @start: start addr
@@ -428,6 +428,10 @@ static int __walk_iomem_res_desc(resource_size_t start, resource_size_t end,
  * @arg: function argument for the callback @func
  * @func: callback function that is called for each qualifying resource area
  *
+ * This walks through whole tree and not just first level children.
+ * All the memory ranges which overlap start,end and also match flags and
+ * desc are valid candidates.
+ *
  * NOTE: For a new descriptor search, define a new IORES_DESC in
  * <linux/ioport.h> and set it in 'desc' of a target resource entry.
  */
@@ -1372,9 +1376,9 @@ static bool system_ram_resources_mergeable(struct resource *r1,
 	       !r1->child && !r2->child;
 }
 
-/*
+/**
  * merge_system_ram_resource - mark the System RAM resource mergeable and try to
- * merge it with adjacent, mergeable resources
+ *	merge it with adjacent, mergeable resources
  * @res: resource descriptor
  *
  * This interface is intended for memory hotplug, whereby lots of contiguous
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index f1022945e346..b5c4b9ade960 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -449,7 +449,7 @@ static struct dentry *blk_create_buf_file_callback(const char *filename,
 					&relay_file_operations);
 }
 
-static struct rchan_callbacks blk_relay_callbacks = {
+static const struct rchan_callbacks blk_relay_callbacks = {
 	.subbuf_start		= blk_subbuf_start_callback,
 	.create_buf_file	= blk_create_buf_file_callback,
 	.remove_buf_file	= blk_remove_buf_file_callback,