5 files changed, 117 insertions, 37 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index c768bcdda1b7..10ef61981149 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -238,6 +238,21 @@ config DETECT_HUNG_TASK
           enabled then all held locks will also be reported. This
           feature has negligible overhead.
 
+config DEFAULT_HUNG_TASK_TIMEOUT
+        int "Default timeout for hung task detection (in seconds)"
+        depends on DETECT_HUNG_TASK
+        default 120
+        help
+          This option controls the default timeout (in seconds) used
+          to determine when a task has become non-responsive and should
+          be considered hung.
+
+          It can be adjusted at runtime via the kernel.hung_task_timeout
+          sysctl or by writing a value to /proc/sys/kernel/hung_task_timeout.
+
+          A timeout of 0 disables the check.  The default is two minutes.
+          Keeping the default should be fine in most cases.
+
 config BOOTPARAM_HUNG_TASK_PANIC
         bool "Panic (Reboot) On Hung Tasks"
         depends on DETECT_HUNG_TASK
@@ -337,7 +352,7 @@ config DEBUG_OBJECTS_WORK
 
 config DEBUG_OBJECTS_RCU_HEAD
         bool "Debug RCU callbacks objects"
-        depends on DEBUG_OBJECTS && PREEMPT
+        depends on DEBUG_OBJECTS
         help
           Enable this to turn on debugging of RCU list heads (call_rcu() usage).
 
@@ -398,9 +413,9 @@ config SLUB_STATS
 config DEBUG_KMEMLEAK
         bool "Kernel memory leak detector"
         depends on DEBUG_KERNEL && EXPERIMENTAL && !MEMORY_HOTPLUG && \
-                (X86 || ARM || PPC || S390 || SPARC64 || SUPERH || MICROBLAZE || TILE)
+                (X86 || ARM || PPC || MIPS || S390 || SPARC64 || SUPERH || MICROBLAZE || TILE)
 
-        select DEBUG_FS if SYSFS
+        select DEBUG_FS
         select STACKTRACE if STACKTRACE_SUPPORT
         select KALLSYMS
         select CRC32
@@ -875,22 +890,9 @@ config RCU_TORTURE_TEST_RUNNABLE
           Say N here if you want the RCU torture tests to start only
           after being manually enabled via /proc.
 
-config RCU_CPU_STALL_DETECTOR
-        bool "Check for stalled CPUs delaying RCU grace periods"
-        depends on TREE_RCU || TREE_PREEMPT_RCU
-        default y
-        help
-          This option causes RCU to printk information on which
-          CPUs are delaying the current grace period, but only when
-          the grace period extends for excessive time periods.
-
-          Say N if you want to disable such checks.
-
-          Say Y if you are unsure.
-
 config RCU_CPU_STALL_TIMEOUT
         int "RCU CPU stall timeout in seconds"
-        depends on RCU_CPU_STALL_DETECTOR
+        depends on TREE_RCU || TREE_PREEMPT_RCU
         range 3 300
         default 60
         help
@@ -899,22 +901,9 @@ config RCU_CPU_STALL_TIMEOUT
           RCU grace period persists, additional CPU stall warnings are
           printed at more widely spaced intervals.
 
-config RCU_CPU_STALL_DETECTOR_RUNNABLE
-        bool "RCU CPU stall checking starts automatically at boot"
-        depends on RCU_CPU_STALL_DETECTOR
-        default y
-        help
-          If set, start checking for RCU CPU stalls immediately on
-          boot.  Otherwise, RCU CPU stall checking must be manually
-          enabled.
-
-          Say Y if you are unsure.
-
-          Say N if you wish to suppress RCU CPU stall checking during boot.
-
 config RCU_CPU_STALL_VERBOSE
         bool "Print additional per-task information for RCU_CPU_STALL_DETECTOR"
-        depends on RCU_CPU_STALL_DETECTOR && TREE_PREEMPT_RCU
+        depends on TREE_PREEMPT_RCU
         default y
         help
           This option causes RCU to printk detailed per-task information
diff --git a/lib/Makefile b/lib/Makefile
index ef0f28571156..4b49a249064b 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -21,7 +21,8 @@ lib-y	+= kobject.o kref.o klist.o
 
 obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
          bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \
-         string_helpers.o gcd.o lcm.o list_sort.o uuid.o flex_array.o
+         string_helpers.o gcd.o lcm.o list_sort.o uuid.o flex_array.o \
+         bsearch.o
 obj-y += kstrtox.o
 obj-$(CONFIG_TEST_KSTRTOX) += test-kstrtox.o
 
diff --git a/lib/bsearch.c b/lib/bsearch.c
new file mode 100644
index 000000000000..5b54758e2afb
--- /dev/null
+++ b/lib/bsearch.c
@@ -0,0 +1,53 @@
+/*
+ * A generic implementation of binary search for the Linux kernel
+ *
+ * Copyright (C) 2008-2009 Ksplice, Inc.
+ * Author: Tim Abbott <tabbott@ksplice.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; version 2.
+ */
+
+#include <linux/module.h>
+#include <linux/bsearch.h>
+
+/*
+ * bsearch - binary search an array of elements
+ * @key: pointer to item being searched for
+ * @base: pointer to first element to search
+ * @num: number of elements
+ * @size: size of each element
+ * @cmp: pointer to comparison function
+ *
+ * This function does a binary search on the given array.  The
+ * contents of the array should already be in ascending sorted order
+ * under the provided comparison function.
+ *
+ * Note that the key need not have the same type as the elements in
+ * the array, e.g. key could be a string and the comparison function
+ * could compare the string with the struct's name field.  However, if
+ * the key and elements in the array are of the same type, you can use
+ * the same comparison function for both sort() and bsearch().
+ */
+void *bsearch(const void *key, const void *base, size_t num, size_t size,
+              int (*cmp)(const void *key, const void *elt))
+{
+        size_t start = 0, end = num;
+        int result;
+
+        while (start < end) {
+                size_t mid = start + (end - start) / 2;
+
+                result = cmp(key, base + mid * size);
+                if (result < 0)
+                        end = mid;
+                else if (result > 0)
+                        start = mid + 1;
+                else
+                        return (void *)base + mid * size;
+        }
+
+        return NULL;
+}
+EXPORT_SYMBOL(bsearch);
diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index 4bfb0471f106..db07bfd9298e 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -649,7 +649,7 @@ out_err:
         return -ENOMEM;
 }
 
-static int device_dma_allocations(struct device *dev)
+static int device_dma_allocations(struct device *dev, struct dma_debug_entry **out_entry)
 {
         struct dma_debug_entry *entry;
         unsigned long flags;
@@ -660,8 +660,10 @@ static int device_dma_allocations(struct device *dev)
         for (i = 0; i < HASH_SIZE; ++i) {
                 spin_lock(&dma_entry_hash[i].lock);
                 list_for_each_entry(entry, &dma_entry_hash[i].list, list) {
-                        if (entry->dev == dev)
+                        if (entry->dev == dev) {
                                 count += 1;
+                                *out_entry = entry;
+                        }
                 }
                 spin_unlock(&dma_entry_hash[i].lock);
         }
@@ -674,6 +676,7 @@ static int device_dma_allocations(struct device *dev)
 static int dma_debug_device_change(struct notifier_block *nb, unsigned long action, void *data)
 {
         struct device *dev = data;
+        struct dma_debug_entry *uninitialized_var(entry);
         int count;
 
         if (global_disable)
@@ -681,12 +684,17 @@ static int dma_debug_device_change(struct notifier_block *nb, unsigned long acti
 
         switch (action) {
         case BUS_NOTIFY_UNBOUND_DRIVER:
-                count = device_dma_allocations(dev);
+                count = device_dma_allocations(dev, &entry);
                 if (count == 0)
                         break;
-                err_printk(dev, NULL, "DMA-API: device driver has pending "
+                err_printk(dev, entry, "DMA-API: device driver has pending "
                                 "DMA allocations while released from device "
-                                "[count=%d]\n", count);
+                                "[count=%d]\n"
+                                "One of leaked entries details: "
+                                "[device address=0x%016llx] [size=%llu bytes] "
+                                "[mapped with %s] [mapped as %s]\n",
+                        count, entry->dev_addr, entry->size,
+                        dir2name[entry->direction], type2name[entry->type]);
                 break;
         default:
                 break;
diff --git a/lib/string.c b/lib/string.c
index f71bead1be3e..01fad9b203e1 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -535,6 +535,35 @@ bool sysfs_streq(const char *s1, const char *s2)
 }
 EXPORT_SYMBOL(sysfs_streq);
 
+/**
+ * strtobool - convert common user inputs into boolean values
+ * @s: input string
+ * @res: result
+ *
+ * This routine returns 0 iff the first character is one of 'Yy1Nn0'.
+ * Otherwise it will return -EINVAL.  Value pointed to by res is
+ * updated upon finding a match.
+ */
+int strtobool(const char *s, bool *res)
+{
+        switch (s[0]) {
+        case 'y':
+        case 'Y':
+        case '1':
+                *res = true;
+                break;
+        case 'n':
+        case 'N':
+        case '0':
+                *res = false;
+                break;
+        default:
+                return -EINVAL;
+        }
+        return 0;
+}
+EXPORT_SYMBOL(strtobool);
+
 #ifndef __HAVE_ARCH_MEMSET
 /**
  * memset - Fill a region of memory with the given value