Commit df43d903 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'printk-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux 

Pull printk updates from Petr Mladek:

 - Optionally, provide an index of possible printk messages via
   <debugfs>/printk/index/. It can be used when monitoring important
   kernel messages on a farm of various hosts. The monitor has to be
   updated when some messages has changed or are not longer available by
   a newly deployed kernel.

 - Add printk.console_no_auto_verbose boot parameter. It allows to
   generate crash dump even with slow consoles in a reasonable time
   frame.

 - Remove printk_safe buffers. The messages are always stored directly
   to the main logbuffer, even in NMI or recursive context. Also it
   allows to serialize syslog operations by a mutex instead of a spin
   lock.

 - Misc clean up and build fixes.

* tag 'printk-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printk/index: Fix -Wunused-function warning
  lib/nmi_backtrace: Serialize even messages about idle CPUs
  printk: Add printk.console_no_auto_verbose boot parameter
  printk: Remove console_silent()
  lib/test_scanf: Handle n_bits == 0 in random tests
  printk: syslog: close window between wait and read
  printk: convert @syslog_lock to mutex
  printk: remove NMI tracking
  printk: remove safe buffers
  printk: track/limit recursion
  lib/nmi_backtrace: explicitly serialize banner and regs
  printk: Move the printk() kerneldoc comment to its new home
  printk/index: Fix warning about missing prototypes
  MIPS/asm/printk: Fix build failure caused by printk
  printk: index: Add indexing support to dev_printk
  printk: Userspace format indexing support
  printk: Rework parse_prefix into printk_parse_prefix
  printk: Straighten out log_flags into printk_info_flags
  string_helpers: Escape double quotes in escape_special
  printk/console: Check consistent sequence number when handling race in console_unlock()
parents 9e5f3ffc c985aafb

Documentation/admin-guide/kernel-parameters.txt

+9 −0
Original line number Diff line number Diff line
@@ -4198,6 +4198,15 @@ 
			Format: <bool>  (1/Y/y=enable, 0/N/n=disable)

			default: disabled



	printk.console_no_auto_verbose=

			Disable console loglevel raise on oops, panic

			or lockdep-detected issues (only if lock debug is on).

			With an exception to setups with low baudrate on

			serial console, keeping this 0 is a good choice

			in order to provide more debug information.

			Format: <bool>

			default: 0 (auto_verbose is enabled)



	printk.devkmsg={on,off,ratelimit}

			Control writing to /dev/kmsg.

			on - unlimited logging to /dev/kmsg from userspace

Documentation/core-api/printk-basics.rst

+1 −4
Original line number Diff line number Diff line
@@ -107,9 +107,6 @@ also ``CONFIG_DYNAMIC_DEBUG`` in the case of pr_debug()) is defined. 
Function reference

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



.. kernel-doc:: kernel/printk/printk.c

   :functions: printk



.. kernel-doc:: include/linux/printk.h

   :functions: pr_emerg pr_alert pr_crit pr_err pr_warn pr_notice pr_info

   :functions: printk pr_emerg pr_alert pr_crit pr_err pr_warn pr_notice pr_info

      pr_fmt pr_debug pr_devel pr_cont

MAINTAINERS

+5 −0
Original line number Diff line number Diff line
@@ -15021,6 +15021,11 @@ S: Maintained 
F:	include/linux/printk.h

F:	kernel/printk/









PRINTK INDEXING









R:	Chris Down <chris@chrisdown.name>









S:	Maintained









F:	kernel/printk/index.c

















PROC FILESYSTEM









L:	linux-kernel@vger.kernel.org









L:	linux-fsdevel@vger.kernel.org
































arch/arm/kernel/entry-v7m.S



+1
−1






























Original line number
Diff line number
Diff line







@@ -23,7 +23,7 @@ __invalid_entry:







	adr	r0, strerr









	mrs	r1, ipsr









	mov	r2, lr









	bl	printk









	bl	_printk









#endif









	mov	r0, sp









	bl	show_regs
































arch/arm/kernel/smp.c



+2
−2






























Original line number
Diff line number
Diff line







@@ -667,9 +667,9 @@ static void do_handle_IPI(int ipinr)







		break;



















	case IPI_CPU_BACKTRACE:









		printk_nmi_enter();









		printk_deferred_enter();









		nmi_cpu_backtrace(get_irq_regs());









		printk_nmi_exit();









		printk_deferred_exit();









		break;



















	default: