Merge tag 'printk-for-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux

Pull printk updates from Petr Mladek:

 - Add %pt[RT]s modifier to vsprintf(). It overrides ISO 8601 separator
   by using ' ' (space). It produces "YYYY-mm-dd HH:MM:SS" instead of
   "YYYY-mm-ddTHH:MM:SS".

 - Correctly parse long row of numbers by sscanf() when using the field
   width. Add extensive sscanf() selftest.

 - Generalize re-entrant CPU lock that has already been used to
   serialize dump_stack() output. It is part of the ongoing printk
   rework. It will allow to remove the obsoleted printk_safe buffers and
   introduce atomic consoles.

 - Some code clean up and sparse warning fixes.

* tag 'printk-for-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printk: fix cpu lock ordering
  lib/dump_stack: move cpu lock to printk.c
  printk: Remove trailing semicolon in macros
  random32: Fix implicit truncation warning in prandom_seed_state()
  lib: test_scanf: Remove pointless use of type_min() with unsigned types
  selftests: lib: Add wrapper script for test_scanf
  lib: test_scanf: Add tests for sscanf number conversion
  lib: vsprintf: Fix handling of number field widths in vsscanf
  lib: vsprintf: scanf: Negative number must have field width > 1
  usb: host: xhci-tegra: Switch to use %ptTs
  nilfs2: Switch to use %ptTs
  kdb: Switch to use %ptTs
  lib/vsprintf: Allow to override ISO 8601 date and time separator

3 files changed, 43 insertions, 2 deletions

diff --git a/include/linux/dev_printk.h b/include/linux/dev_printk.h
index 6f009559ee54..82d3d46005a1 100644
--- a/include/linux/dev_printk.h
+++ b/include/linux/dev_printk.h
@@ -236,7 +236,7 @@ do {									\
  * using WARN/WARN_ONCE to include file/line information and a backtrace.
  */
 #define dev_WARN(dev, format, arg...) \
-	WARN(1, "%s %s: " format, dev_driver_string(dev), dev_name(dev), ## arg);
+	WARN(1, "%s %s: " format, dev_driver_string(dev), dev_name(dev), ## arg)
 
 #define dev_WARN_ONCE(dev, condition, format, arg...) \
 	WARN_ONCE(condition, "%s %s: " format, \
diff --git a/include/linux/prandom.h b/include/linux/prandom.h
index bbf4b4ad61df..056d31317e49 100644
--- a/include/linux/prandom.h
+++ b/include/linux/prandom.h
@@ -111,7 +111,7 @@ static inline u32 __seed(u32 x, u32 m)
  */
 static inline void prandom_seed_state(struct rnd_state *state, u64 seed)
 {
-	u32 i = (seed >> 32) ^ (seed << 10) ^ seed;
+	u32 i = ((seed >> 32) ^ (seed << 10) ^ seed) & 0xffffffffUL;
 
 	state->s1 = __seed(i,   2U);
 	state->s2 = __seed(i,   8U);
diff --git a/include/linux/printk.h b/include/linux/printk.h
index fe7eb2351610..1790a5521fd9 100644
--- a/include/linux/printk.h
+++ b/include/linux/printk.h
@@ -282,6 +282,47 @@ static inline void printk_safe_flush_on_panic(void)
 }
 #endif
 
+#ifdef CONFIG_SMP
+extern int __printk_cpu_trylock(void);
+extern void __printk_wait_on_cpu_lock(void);
+extern void __printk_cpu_unlock(void);
+
+/**
+ * printk_cpu_lock_irqsave() - Acquire the printk cpu-reentrant spinning
+ *                             lock and disable interrupts.
+ * @flags: Stack-allocated storage for saving local interrupt state,
+ *         to be passed to printk_cpu_unlock_irqrestore().
+ *
+ * If the lock is owned by another CPU, spin until it becomes available.
+ * Interrupts are restored while spinning.
+ */
+#define printk_cpu_lock_irqsave(flags)		\
+	for (;;) {				\
+		local_irq_save(flags);		\
+		if (__printk_cpu_trylock())	\
+			break;			\
+		local_irq_restore(flags);	\
+		__printk_wait_on_cpu_lock();	\
+	}
+
+/**
+ * printk_cpu_unlock_irqrestore() - Release the printk cpu-reentrant spinning
+ *                                  lock and restore interrupts.
+ * @flags: Caller's saved interrupt state, from printk_cpu_lock_irqsave().
+ */
+#define printk_cpu_unlock_irqrestore(flags)	\
+	do {					\
+		__printk_cpu_unlock();		\
+		local_irq_restore(flags);	\
+	} while (0)				\
+
+#else
+
+#define printk_cpu_lock_irqsave(flags) ((void)flags)
+#define printk_cpu_unlock_irqrestore(flags) ((void)flags)
+
+#endif /* CONFIG_SMP */
+
 extern int kptr_restrict;
 
 /**