Re: [PATCH 0/3] x86/dumpstack: Print registers with the same log level as the backtrace

From: Petr Mladek
Date: Wed Jun 24 2020 - 02:51:03 EST


On Tue 2020-06-23 17:29:55, Dmitry Safonov wrote:
> show_trace_log_lvl() provides x86 platform-specific way to unwind
> backtrace with a given log level. Unfortunately, registers dump(s) are
> not printed with the same log level - instead, KERN_DEFAULT is always
> used.
>
> Arista's switches uses quite common setup with rsyslog, where only
> urgent messages goes to console (console_log_level=KERN_ERR), everything
> else goes into /var/log/ as the console baud-rate often is indecently
> slow (9600 bps).
>
> Backtrace dumps without registers printed have proven to be as useful as
> morning standups. Furthermore, in order to introduce KERN_UNSUPPRESSED
> (which I believe is still the most elegant way to fix raciness of sysrq[1])
> the log level should be passed down the stack to register dumping
> functions. Besides, I have a potential use-case for printing traces
> with KERN_DEBUG level [2] (where registers dump shouldn't appear with
> higher log level than the backtrace).
>
> Dmitry Safonov (3):
> x86/dumpstack: Add log_lvl to show_iret_regs()
> x86/dumpstack: Add log_lvl to __show_regs()
> x86/dumpstack: Show registers dump with trace's log level

The change makes sense. It is natural next step after adding log_lvl
parameter for printing stack traces. For the entire patchset:

Acked-by: Petr Mladek <pmladek@xxxxxxxx>

Are there any plans to add this also for other architectures, please?

Best Regards,
Petr