Messages in this thread | | | From | Dmitry Vyukov <> | Date | Sat, 16 Mar 2019 16:10:15 +0100 | Subject | Re: [syzbot? printk?] no WARN_ON() messages printed before "Kernel panic - not syncing: panic_on_warn set ..." |
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On Sat, Mar 16, 2019 at 4:02 PM Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> wrote: > > 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 ?
Is there a single place to catch this? I could run syzkaller locally first with the check.
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