1 files changed, 127 insertions, 50 deletions

diff --git a/kernel/printk.c b/kernel/printk.c
index 0b31715f335a..96dcfcd9a2d4 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -43,19 +43,13 @@
 #include <linux/rculist.h>
 #include <linux/poll.h>
 #include <linux/irq_work.h>
+#include <linux/utsname.h>
 
 #include <asm/uaccess.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/printk.h>
 
-/*
- * Architectures can override it:
- */
-void asmlinkage __attribute__((weak)) early_printk(const char *fmt, ...)
-{
-}
-
 /* printk's without a loglevel use this.. */
 #define DEFAULT_MESSAGE_LOGLEVEL CONFIG_DEFAULT_MESSAGE_LOGLEVEL
 
@@ -63,8 +57,6 @@ void asmlinkage __attribute__((weak)) early_printk(const char *fmt, ...)
 #define MINIMUM_CONSOLE_LOGLEVEL 1 /* Minimum loglevel we let people use */
 #define DEFAULT_CONSOLE_LOGLEVEL 7 /* anything MORE serious than KERN_DEBUG */
 
-DECLARE_WAIT_QUEUE_HEAD(log_wait);
-
 int console_printk[4] = {
         DEFAULT_CONSOLE_LOGLEVEL,       /* console_loglevel */
         DEFAULT_MESSAGE_LOGLEVEL,       /* default_message_loglevel */
@@ -224,6 +216,7 @@ struct log {
 static DEFINE_RAW_SPINLOCK(logbuf_lock);
 
 #ifdef CONFIG_PRINTK
+DECLARE_WAIT_QUEUE_HEAD(log_wait);
 /* the next printk record to read by syslog(READ) or /proc/kmsg */
 static u64 syslog_seq;
 static u32 syslog_idx;
@@ -609,7 +602,8 @@ static unsigned int devkmsg_poll(struct file *file, poll_table *wait)
                 /* return error when data has vanished underneath us */
                 if (user->seq < log_first_seq)
                         ret = POLLIN|POLLRDNORM|POLLERR|POLLPRI;
-                ret = POLLIN|POLLRDNORM;
+                else
+                        ret = POLLIN|POLLRDNORM;
         }
         raw_spin_unlock_irq(&logbuf_lock);
 
@@ -1266,7 +1260,7 @@ static void call_console_drivers(int level, const char *text, size_t len)
 {
         struct console *con;
 
-        trace_console(text, 0, len, len);
+        trace_console(text, len);
 
         if (level >= console_loglevel && !ignore_loglevel)
                 return;
@@ -1724,6 +1718,29 @@ static size_t cont_print_text(char *text, size_t size) { return 0; }
 
 #endif /* CONFIG_PRINTK */
 
+#ifdef CONFIG_EARLY_PRINTK
+struct console *early_console;
+
+void early_vprintk(const char *fmt, va_list ap)
+{
+        if (early_console) {
+                char buf[512];
+                int n = vscnprintf(buf, sizeof(buf), fmt, ap);
+
+                early_console->write(early_console, buf, n);
+        }
+}
+
+asmlinkage void early_printk(const char *fmt, ...)
+{
+        va_list ap;
+
+        va_start(ap, fmt);
+        early_vprintk(fmt, ap);
+        va_end(ap);
+}
+#endif
+
 static int __add_preferred_console(char *name, int idx, char *options,
                                    char *brl_options)
 {
@@ -1957,45 +1974,6 @@ int is_console_locked(void)
         return console_locked;
 }
 
-/*
- * Delayed printk version, for scheduler-internal messages:
- */
-#define PRINTK_BUF_SIZE         512
-
-#define PRINTK_PENDING_WAKEUP   0x01
-#define PRINTK_PENDING_SCHED    0x02
-
-static DEFINE_PER_CPU(int, printk_pending);
-static DEFINE_PER_CPU(char [PRINTK_BUF_SIZE], printk_sched_buf);
-
-static void wake_up_klogd_work_func(struct irq_work *irq_work)
-{
-        int pending = __this_cpu_xchg(printk_pending, 0);
-
-        if (pending & PRINTK_PENDING_SCHED) {
-                char *buf = __get_cpu_var(printk_sched_buf);
-                printk(KERN_WARNING "[sched_delayed] %s", buf);
-        }
-
-        if (pending & PRINTK_PENDING_WAKEUP)
-                wake_up_interruptible(&log_wait);
-}
-
-static DEFINE_PER_CPU(struct irq_work, wake_up_klogd_work) = {
-        .func = wake_up_klogd_work_func,
-        .flags = IRQ_WORK_LAZY,
-};
-
-void wake_up_klogd(void)
-{
-        preempt_disable();
-        if (waitqueue_active(&log_wait)) {
-                this_cpu_or(printk_pending, PRINTK_PENDING_WAKEUP);
-                irq_work_queue(&__get_cpu_var(wake_up_klogd_work));
-        }
-        preempt_enable();
-}
-
 static void console_cont_flush(char *text, size_t size)
 {
         unsigned long flags;
@@ -2458,6 +2436,44 @@ static int __init printk_late_init(void)
 late_initcall(printk_late_init);
 
 #if defined CONFIG_PRINTK
+/*
+ * Delayed printk version, for scheduler-internal messages:
+ */
+#define PRINTK_BUF_SIZE         512
+
+#define PRINTK_PENDING_WAKEUP   0x01
+#define PRINTK_PENDING_SCHED    0x02
+
+static DEFINE_PER_CPU(int, printk_pending);
+static DEFINE_PER_CPU(char [PRINTK_BUF_SIZE], printk_sched_buf);
+
+static void wake_up_klogd_work_func(struct irq_work *irq_work)
+{
+        int pending = __this_cpu_xchg(printk_pending, 0);
+
+        if (pending & PRINTK_PENDING_SCHED) {
+                char *buf = __get_cpu_var(printk_sched_buf);
+                printk(KERN_WARNING "[sched_delayed] %s", buf);
+        }
+
+        if (pending & PRINTK_PENDING_WAKEUP)
+                wake_up_interruptible(&log_wait);
+}
+
+static DEFINE_PER_CPU(struct irq_work, wake_up_klogd_work) = {
+        .func = wake_up_klogd_work_func,
+        .flags = IRQ_WORK_LAZY,
+};
+
+void wake_up_klogd(void)
+{
+        preempt_disable();
+        if (waitqueue_active(&log_wait)) {
+                this_cpu_or(printk_pending, PRINTK_PENDING_WAKEUP);
+                irq_work_queue(&__get_cpu_var(wake_up_klogd_work));
+        }
+        preempt_enable();
+}
 
 int printk_sched(const char *fmt, ...)
 {
@@ -2834,4 +2850,65 @@ void kmsg_dump_rewind(struct kmsg_dumper *dumper)
         raw_spin_unlock_irqrestore(&logbuf_lock, flags);
 }
 EXPORT_SYMBOL_GPL(kmsg_dump_rewind);
+
+static char dump_stack_arch_desc_str[128];
+
+/**
+ * dump_stack_set_arch_desc - set arch-specific str to show with task dumps
+ * @fmt: printf-style format string
+ * @...: arguments for the format string
+ *
+ * The configured string will be printed right after utsname during task
+ * dumps.  Usually used to add arch-specific system identifiers.  If an
+ * arch wants to make use of such an ID string, it should initialize this
+ * as soon as possible during boot.
+ */
+void __init dump_stack_set_arch_desc(const char *fmt, ...)
+{
+        va_list args;
+
+        va_start(args, fmt);
+        vsnprintf(dump_stack_arch_desc_str, sizeof(dump_stack_arch_desc_str),
+                  fmt, args);
+        va_end(args);
+}
+
+/**
+ * dump_stack_print_info - print generic debug info for dump_stack()
+ * @log_lvl: log level
+ *
+ * Arch-specific dump_stack() implementations can use this function to
+ * print out the same debug information as the generic dump_stack().
+ */
+void dump_stack_print_info(const char *log_lvl)
+{
+        printk("%sCPU: %d PID: %d Comm: %.20s %s %s %.*s\n",
+               log_lvl, raw_smp_processor_id(), current->pid, current->comm,
+               print_tainted(), init_utsname()->release,
+               (int)strcspn(init_utsname()->version, " "),
+               init_utsname()->version);
+
+        if (dump_stack_arch_desc_str[0] != '\0')
+                printk("%sHardware name: %s\n",
+                       log_lvl, dump_stack_arch_desc_str);
+
+        print_worker_info(log_lvl, current);
+}
+
+/**
+ * show_regs_print_info - print generic debug info for show_regs()
+ * @log_lvl: log level
+ *
+ * show_regs() implementations can use this function to print out generic
+ * debug information.
+ */
+void show_regs_print_info(const char *log_lvl)
+{
+        dump_stack_print_info(log_lvl);
+
+        printk("%stask: %p ti: %p task.ti: %p\n",
+               log_lvl, current, current_thread_info(),
+               task_thread_info(current));
+}
+
 #endif