lkml.org 
[lkml]   [2019]   [Mar]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [syzbot? printk?] no WARN_ON() messages printed before "Kernel panic - not syncing: panic_on_warn set ..."
From
Date
On 2019/03/16 23:57, Dmitry Vyukov wrote:
> On Sat, Mar 16, 2019 at 3:53 PM Tetsuo Handa
> <penguin-kernel@i-love.sakura.ne.jp> wrote:
>>
>> On 2019/03/16 23:16, Dmitry Vyukov wrote:
>>>>> Maybe try running with "ignore_loglevel" kernel command line option added?
>>>>
>>>> Right, that's something I would expect 0-day and syzkaller to do.
>>>
>>> to double-check: enabling this won't lead to verbose/debug level of logging?
>>>
>>
>> I don't know what "verbose/debug level" means. But enabling this option causes
>> KERN_{EMERG,ALERT,CRIT,ERR,WARNING,NOTICE,INFO,DEBUG} be printed equally.
>>
>> "ignore loglevel setting (prints all kernel messages to the console)"
>>
>> static bool suppress_message_printing(int level)
>> {
>> return (level >= console_loglevel && !ignore_loglevel);
>> }
>
> Then I don't think it's suitable: there will be too much output.
>

Then, we need to find what test is changing console_loglevel.
Maybe add debug BUG_ON() in linux-next.git using CONFIG_DEBUG_AID_FOR_SYZBOT ?

\
 
 \ /
  Last update: 2019-03-16 16:03    [W:0.065 / U:0.232 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site