[PATCH v2 00/10] powerpc: Modernize unhandled signals message

[Murilo Opsfelder Araujo <muriloo@linux.ibm.com>]

Hi, everyone.

This series was inspired by the need to modernize and display more
informative messages about unhandled signals.

The "unhandled signal NN" is not very informative.  We thought it would be
helpful adding a human-readable message describing what the signal number
means, printing the VMA address, and dumping the instructions.

We can add more informative messages, like informing what each code of a
SIGSEGV signal means.  We are open to suggestions.

Before this series:

    pandafault[5815]: unhandled signal 11 at 00000000100007d0 nip 000000001000061c lr 00003fff87ff5100 code 2

After this series:

    pandafault[10850]: segfault (11) at 00000000100007d0 nip 000000001000061c lr 00007fff9f3e5100 code 2 in pandafault[10000000+10000]
    pandafault[10850]: code: 4bfffeec 4bfffee8 3c401002 38427f00 fbe1fff8 f821ffc1 7c3f0b78 3d22fffe
    pandafault[10850]: code: 392988d0 f93f0020 e93f0020 39400048 <99490000> 39200000 7d234b78 383f0040

Link to v1:

    https://lore.kernel.org/lkml/20180724192720.32417-1-muriloo@linux.ibm.com/

v1..v2:

    - Broke patch 7 down into patches 7-9
    - Added proper copyright in arch/powerpc/include/asm/stacktrace.h
    - show_instructions(): prefixed lines with current->comm and current->pid

Cheers!

Murilo Opsfelder Araujo (10):
  powerpc/traps: Print unhandled signals in a separate function
  powerpc/traps: Return early in show_signal_msg()
  powerpc/reg: Add REG_FMT definition
  powerpc/traps: Use REG_FMT in show_signal_msg()
  powerpc/traps: Print VMA for unhandled signals
  powerpc/traps: Print signal name for unhandled signals
  powerpc: Do not call __kernel_text_address() in show_instructions()
  powerpc: Add stacktrace.h header
  powerpc/traps: Show instructions on exceptions
  powerpc/traps: Add line prefix in show_instructions()

 arch/powerpc/include/asm/reg.h        |  6 +++
 arch/powerpc/include/asm/stacktrace.h | 13 +++++
 arch/powerpc/kernel/process.c         | 35 ++++++-------
 arch/powerpc/kernel/traps.c           | 73 +++++++++++++++++++++++----
 4 files changed, 100 insertions(+), 27 deletions(-)
 create mode 100644 arch/powerpc/include/asm/stacktrace.h

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2.17.1