Re: [PATCH V2] docs: panic: Disclaimer about console verbosity when using panic_print with pstore

[Jonathan Corbet <corbet@lwn.net>]

"Guilherme G. Piccoli" <gpiccoli@igalia.com> writes:

> Users of panic_print / panic_sys_info are usually aware of the potentially
> huge amount of information displayed with such options - their goal by
> using them is indeed to dump more information during panic!
>
> What might come unnoticed at first is the impact that the console_verbose()
> call on panic path has, specially in cases that users rely on pstore as
> a means to collect the panic logs. Recent experience shows that dumping
> all tasks in an ARM64 system (with qcom_geni tty driver) gets a 2 minute
> delay on panic time due to writing such information to console. But in
> that case, pstore was used, so there was no need for console printing,
> and suppressing that reduced the full time to less than 0.5 second.
>
> The option "printk.console_no_auto_verbose" aims exactly at this use
> case: avoid automatically increasing the loglevel during panic path.
> So, let's officially document this to avoid users wasting their time
> either on long panic printing or debugging the panic delays.
>
> While at it, improve the readability of the panic_print text, by
> adding some line breaks.
>
> Suggested-by: Petr Mladek <pmladek@suse.com>
> Reviewed-by: Bradley Morgan <include@grrlz.net>
> Reviewed-by: Feng Tang <feng.tang@linux.alibaba.com>
> Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
> ---
>
>
> V2:
> - Added line breaks as per Petr's suggestion (with some text improvements
>   as well) - thanks Petr!
>
> - Added review tags - thanks Feng Tang and Bradley, feel free to check
>   again given we added the line breaks, etc.
>
> V1 link: https://lore.kernel.org/r/20260805205026.1699568-1-gpiccoli@igalia.com/
>
>
>  .../admin-guide/kernel-parameters.txt         | 19 ++++++++++++++-----
>  1 file changed, 14 insertions(+), 5 deletions(-)

Applied, thanks.

jon