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Subject[PATCH v2 0/3] x86/dumpstack: Print registers with the same log level as the backtrace
Changes since v1 [3]:
- Use (enum show_regs_mode) instead of (int) [nit by Jann, thanks!]
- Add acks from Petr

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

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).

Cc: Andy Lutomirski <>
Cc: Borislav Petkov <>
Cc: "H. Peter Anvin" <>
Cc: Ingo Molnar <>
Cc: Jann Horn <>
Cc: Petr Mladek <>
Cc: Sergey Senozhatsky <>
Cc: Steven Rostedt <>
Cc: Tetsuo Handa <>
Cc: Thomas Gleixner <>
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

arch/x86/include/asm/kdebug.h | 5 ++--
arch/x86/kernel/dumpstack.c | 23 +++++++++-------
arch/x86/kernel/process_32.c | 29 ++++++++++----------
arch/x86/kernel/process_64.c | 51 ++++++++++++++++++-----------------
4 files changed, 57 insertions(+), 51 deletions(-)


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