A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-28 10:41:38 -04:00
Code Issues Projects Releases Packages Wiki Activity

panic: add an option to replay all the printk message in buffer

Browse source 
Currently on panic, kernel will lower the loglevel and print out pending
printk msg only with console_flush_on_panic().

Add an option for users to configure the "panic_print" to replay all
dmesg in buffer, some of which they may have never seen due to the
loglevel setting, which will help panic debugging .

[[email protected]: keep the original console_flush_on_panic() inside panic()]
  Link: http://lkml.kernel.org/r/[email protected]
[[email protected]: use logbuf lock to protect the console log index]
  Link: http://lkml.kernel.org/r/[email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Feng Tang <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Cc: Aaro Koskinen <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Borislav Petkov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
Feng Tang 2019-05-17 14:31:50 -07:00 • committed by Linus Torvalds
commit de6da1e8bc
5 changed files with 24 additions and 4 deletions
Download patch file Download diff file Expand all files Collapse all files

12
kernel/printk/printk.c
View file

@ -2535,10 +2535,11 @@ void console_unblank(void)
/**
* console_flush_on_panic - flush console content on panic
* @mode: flush all messages in buffer or just the pending ones
*
* Immediately output all pending messages no matter what.
*/
void console_flush_on_panic(void)
void console_flush_on_panic(enum con_flush_mode mode)
{
/*
* If someone else is holding the console lock, trylock will fail
@ -2549,6 +2550,15 @@ void console_flush_on_panic(void)
*/
console_trylock();
console_may_schedule = 0;
if (mode == CONSOLE_REPLAY_ALL) {
unsigned long flags;
logbuf_lock_irqsave(flags);
console_seq = log_first_seq;
console_idx = log_first_idx;
logbuf_unlock_irqrestore(flags);
}
console_unlock();
}