Bug #13566

A process freezes at the beginning of C level backtrace when a certain SEGV is occurred

Added by mrkn (Kenta Murata) about 3 years ago. Updated over 2 years ago.

Target version:
ruby -v:
ruby 2.4.1p111 (2017-03-22 revision 58053) [x86_64-darwin16]


I found the issue that a process freezes at the beginning of C level backtrace printing when a certain SEGV is occurred.

I've made a reproducible code in the freeze_on_segv branch of pycall project.
You can check it by the following steps:

$ git clone
$ git checkout -t origin/freeze_on_segv
$ bundle install
$ bin/runner callback.rb

When you succeed to reproduce the issue, you can see the following output:

$ bin/runner callback.rb
{#<FFI::Pointer address=0x00000109057d10>=>[#<Proc:0x007fbb411b93e8@callback.rb:1>]}
callback.rb:11: [BUG] Segmentation fault at 0x00000000000000
ruby 2.4.1p111 (2017-03-22 revision 58053) [x86_64-darwin16]

-- Crash Report log information --------------------------------------------
   See Crash Report log file under the one of following:
     * ~/Library/Logs/DiagnosticReports
     * /Library/Logs/DiagnosticReports
   for more details.
Don't forget to include the above Crash Report log file in bug reports.

-- Control frame information -----------------------------------------------
c:0005 p:---- s:0021 e:000020 CFUNC  :Py_DecRef
c:0004 p:0105 s:0016 E:002530 TOP    callback.rb:11 [FINISH]
c:0003 p:---- s:0011 e:000010 CFUNC  :load
c:0002 p:0034 s:0006 e:000005 EVAL   bin/runner:6 [FINISH]
c:0001 p:0000 s:0003 E:0013a0 (none) [FINISH]

-- Ruby level backtrace information ----------------------------------------
bin/runner:6:in `<main>'
bin/runner:6:in `load'
callback.rb:11:in `<top (required)>'
callback.rb:11:in `Py_DecRef'

-- Machine register context ------------------------------------------------
 rax: 0x00007fbb43667950 rbx: 0x729546a3ab9700ab rcx: 0x00007fbb40d05190
 rdx: 0x00007fbb40d05190 rdi: 0x0000000109057d10 rsi: 0x00007fbb411e0358
 rbp: 0x00007fff577eb6c0 rsp: 0x00007fff577eb6b8  r8: 0x00007fff577eb6e0
  r9: 0x00000001085e46a1 r10: 0x00007fff577eb610 r11: 0x0000000108ca1d30
 r12: 0x0000000000000000 r13: 0x0000000000000001 r14: 0x729546a3ab9700ab
 r15: 0x00007fff577eb7d0 rip: 0x0000000000000000 rfl: 0x0000000000010246

-- C level backtrace information -------------------------------------------

At this point, C-c doesn't work.

Related issues

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