From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 6 Jun 2018 23:04:55 +0000 (-0700)
Subject: Merge tag 'printk-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek... 
X-Git-Url: http://git.rot13.org/?a=commitdiff_plain;h=d75ae5bdf2353e5c6a1f83da5f6f2d31582f09a3;p=linux

Merge tag 'printk-for-4.18' of git://git./linux/kernel/git/pmladek/printk

Pull printk updates from Petr Mladek:

 - Help userspace log daemons to catch up with a flood of messages. They
   will get woken after each message even if the console is far behind
   and handled by another process.

 - Flush printk safe buffers safely even when panic() happens in the
   normal context.

 - Fix possible va_list reuse when race happened in printk_safe().

 - Remove %pCr printf format to prevent sleeping in the atomic context.

 - Misc vsprintf code cleanup.

* tag 'printk-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
  printk: drop in_nmi check from printk_safe_flush_on_panic()
  lib/vsprintf: Remove atomic-unsafe support for %pCr
  serial: sh-sci: Stop using printk format %pCr
  thermal: bcm2835: Stop using printk format %pCr
  clk: renesas: cpg-mssr: Stop using printk format %pCr
  printk: fix possible reuse of va_list variable
  printk: wake up klogd in vprintk_emit
  vsprintf: Tweak pF/pf comment
  lib/vsprintf: Mark expected switch fall-through
  lib/vsprintf: Replace space with '_' before crng is ready
  lib/vsprintf: Deduplicate pointer_string()
  lib/vsprintf: Move pointer_string() upper
  lib/vsprintf: Make flag_spec global
  lib/vsprintf: Make strspec global
  lib/vsprintf: Make dec_spec global
  lib/test_printf: Mark big constant with UL
---

d75ae5bdf2353e5c6a1f83da5f6f2d31582f09a3
diff --cc lib/vsprintf.c
index 23920c5ff728,8999202ad43b..a48aaa79d352
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@@ -1655,36 -1641,19 +1651,22 @@@ char *device_node_string(char *buf, cha
  	return widen_string(buf, buf - buf_start, end, spec);
  }
  
- static noinline_for_stack
- char *pointer_string(char *buf, char *end, const void *ptr,
- 		     struct printf_spec spec)
- {
- 	spec.base = 16;
- 	spec.flags |= SMALL;
- 	if (spec.field_width == -1) {
- 		spec.field_width = 2 * sizeof(ptr);
- 		spec.flags |= ZEROPAD;
- 	}
- 
- 	return number(buf, end, (unsigned long int)ptr, spec);
- }
- 
 -static bool have_filled_random_ptr_key __read_mostly;
 +static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
  static siphash_key_t ptr_key __read_mostly;
  
 -static void fill_random_ptr_key(struct random_ready_callback *unused)
 +static void enable_ptr_key_workfn(struct work_struct *work)
  {
  	get_random_bytes(&ptr_key, sizeof(ptr_key));
 -	/*
 -	 * have_filled_random_ptr_key==true is dependent on get_random_bytes().
 -	 * ptr_to_id() needs to see have_filled_random_ptr_key==true
 -	 * after get_random_bytes() returns.
 -	 */
 -	smp_mb();
 -	WRITE_ONCE(have_filled_random_ptr_key, true);
 +	/* Needs to run from preemptible context */
 +	static_branch_disable(&not_filled_random_ptr_key);
 +}
 +
 +static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);
 +
 +static void fill_random_ptr_key(struct random_ready_callback *unused)
 +{
 +	/* This may be in an interrupt handler. */
 +	queue_work(system_unbound_wq, &enable_ptr_key_work);
  }
  
  static struct random_ready_callback random_ready = {
@@@ -1710,13 -1678,13 +1692,13 @@@ early_initcall(initialize_ptr_random)
  /* Maps a pointer to a 32 bit unique identifier. */
  static char *ptr_to_id(char *buf, char *end, void *ptr, struct printf_spec spec)
  {
+ 	const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
  	unsigned long hashval;
- 	const int default_width = 2 * sizeof(ptr);
  
 -	if (unlikely(!have_filled_random_ptr_key)) {
 +	if (static_branch_unlikely(&not_filled_random_ptr_key)) {
- 		spec.field_width = default_width;
+ 		spec.field_width = 2 * sizeof(ptr);
  		/* string length must be less than default_width */
- 		return string(buf, end, "(ptrval)", spec);
+ 		return string(buf, end, str, spec);
  	}
  
  #ifdef CONFIG_64BIT