Messages in this thread | | | Date | Tue, 14 Jun 2022 10:38:57 +0200 | From | Petr Mladek <> | Subject | Re: [BUG] Threaded printk breaks early debugging |
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On Mon 2022-06-13 18:20:03, Peter Geis wrote: > On Mon, Jun 13, 2022 at 11:11 AM Petr Mladek <pmladek@suse.com> wrote: > > > > On Mon 2022-06-13 04:29:50, John Ogness wrote: > > > On 2022-06-12, Peter Geis <pgwipeout@gmail.com> wrote: > > > > The buffer isn't an issue here, everything is available in dmesg when > > > > userspace becomes available. Instead some messages bound for the > > > > serial console are never output. > > > > > > OK. Good to know. > > > > > > > We run a serial console at 1.5m baud which is significantly higher > > > > than most SoCs which default to 115200. I have noticed some timing > > > > differences since the introduction of the threaded console. A > > > > significant amount of information is dumped very early in the boot > > > > process (between 0 and 4 seconds into boot), as most drivers are > > > > probing during this time. It also happens to be when the earlycon > > > > console hands over to the normal console. There is no abnormal > > > > debugging enabled, the output is a standard (non-quiet) boot log. The > > > > question is why is direct mode not triggering during a panic? > > > > > > Just to be clear, you are not losing any intermediate messages. Only the > > > tail end of the kernel log was never printed. Is this correct? > > > > > > This may be the same issue being discussed here [0]. > > > > > > John Ogness > > > > > > [0] https://lore.kernel.org/all/87v8t5l39z.fsf@jogness.linutronix.de > > > > If the last messages are missing then it is most likely the same > > issue. > > > > Peter, could you please try if the patch at > > https://lore.kernel.org/r/YqdSw/fJvnkRbjvc@alley > > would make any difference? > > This patch permits the panic to come through to the console port. Thank you! > Tested-by: Peter Geis <pgwipeout@gmail.com>
Great news. Thanks a lot for feedback.
I guess that the patch is not final. But it seems to be a good direction.
Best Regards, Petr
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