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Dmitry Safonov authored
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, there is a potential use-case for printing traces with KERN_DEBUG level [2] (where registers dump shouldn't appear with higher log level). After all preparations are done, provide log_lvl parameter for show_regs_if_on_stack() and wire up to actual log level used as an argument for show_trace_log_lvl(). [1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/ [2]: https://lore.kernel.org/linux-doc/20190724170249.9644-1-dima@arista.com/Signed-off-by:
Dmitry Safonov <dima@arista.com> Signed-off-by:
Thomas Gleixner <tglx@linutronix.de> Acked-by:
Petr Mladek <pmladek@suse.com> Link: https://lkml.kernel.org/r/20200629144847.492794-4-dima@arista.com
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