3 files changed, 39 insertions, 17 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 9638d99644af..c6e854f215fa 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -186,6 +186,44 @@ config BOOTPARAM_SOFTLOCKUP_PANIC_VALUE
         default 0 if !BOOTPARAM_SOFTLOCKUP_PANIC
         default 1 if BOOTPARAM_SOFTLOCKUP_PANIC
 
+config DETECT_HUNG_TASK
+        bool "Detect Hung Tasks"
+        depends on DEBUG_KERNEL
+        default DETECT_SOFTLOCKUP
+        help
+          Say Y here to enable the kernel to detect "hung tasks",
+          which are bugs that cause the task to be stuck in
+          uninterruptible "D" state indefinitiley.
+
+          When a hung task is detected, the kernel will print the
+          current stack trace (which you should report), but the
+          task will stay in uninterruptible state. If lockdep is
+          enabled then all held locks will also be reported. This
+          feature has negligible overhead.
+
+config BOOTPARAM_HUNG_TASK_PANIC
+        bool "Panic (Reboot) On Hung Tasks"
+        depends on DETECT_HUNG_TASK
+        help
+          Say Y here to enable the kernel to panic on "hung tasks",
+          which are bugs that cause the kernel to leave a task stuck
+          in uninterruptible "D" state.
+
+          The panic can be used in combination with panic_timeout,
+          to cause the system to reboot automatically after a
+          hung task has been detected. This feature is useful for
+          high-availability systems that have uptime guarantees and
+          where a hung tasks must be resolved ASAP.
+
+          Say N if unsure.
+
+config BOOTPARAM_HUNG_TASK_PANIC_VALUE
+        int
+        depends on DETECT_HUNG_TASK
+        range 0 1
+        default 0 if !BOOTPARAM_HUNG_TASK_PANIC
+        default 1 if BOOTPARAM_HUNG_TASK_PANIC
+
 config SCHED_DEBUG
         bool "Collect scheduler debugging info"
         depends on DEBUG_KERNEL && PROC_FS
diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index 32e2bd3b1142..2b0b5a7d2ced 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -549,7 +549,7 @@ swiotlb_alloc_coherent(struct device *hwdev, size_t size,
         dma_addr_t dev_addr;
         void *ret;
         int order = get_order(size);
-        u64 dma_mask = DMA_32BIT_MASK;
+        u64 dma_mask = DMA_BIT_MASK(32);
 
         if (hwdev && hwdev->coherent_dma_mask)
                 dma_mask = hwdev->coherent_dma_mask;
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index be3001f912e4..7536acea135b 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1051,13 +1051,6 @@ int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
                         if (str < end)
                                 *str = '%';
                         ++str;
-                        if (*fmt) {
-                                if (str < end)
-                                        *str = *fmt;
-                                ++str;
-                        } else {
-                                --fmt;
-                        }
                         break;
 
                 case FORMAT_TYPE_NRCHARS: {
@@ -1339,8 +1332,6 @@ do {									\
                         break;
 
                 case FORMAT_TYPE_INVALID:
-                        if (!*fmt)
-                                --fmt;
                         break;
 
                 case FORMAT_TYPE_NRCHARS: {
@@ -1523,13 +1514,6 @@ int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
                         if (str < end)
                                 *str = '%';
                         ++str;
-                        if (*fmt) {
-                                if (str < end)
-                                        *str = *fmt;
-                                ++str;
-                        } else {
-                                --fmt;
-                        }
                         break;
 
                 case FORMAT_TYPE_NRCHARS: