[GIT PULL] printk for 4.21

[Petr Mladek]

Linus,

please pull the latest printk changes from

  git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk tags/printk-for-4.21

==================

- Keep spinlocks busted until the end of panic()

- Fix races between calculating number of messages that would fit
  into user space buffers, filling the buffers, and switching
  printk.time parameter

- Some code clean up

----------------------------------------------------------------
Sergey Senozhatsky (1):
      panic: avoid deadlocks in re-entrant console drivers

Tetsuo Handa (3):
      printk: Make printk_emit() local function.
      printk: fix printk_time race.
      printk: Remove print_prefix() calls with NULL buffer.

 include/linux/printk.h |   5 --
 kernel/panic.c         |   6 ++-
 kernel/printk/printk.c | 131 ++++++++++++++++++++++++-------------------------
 3 files changed, 68 insertions(+), 74 deletions(-)