Crash Dump Analysis Patterns (Part 180, Mac OS X)

This is the first pattern that emerged after applying the same pattern-driven software diagnostics methodology to Mac OS X. I had problems using GDB which is so portable that hardly has operating system support like WinDbg has. Fortunately, I found a workaround by complementing core dumps with logs and reports from OS such as crash reports and vmmap data. I call this pattern Paratext which I borrowed from the concept of an extended software trace and software narratology where it borrowed the same concept from literary interpretation (paratext). Typical examples of such pattern usage can be the list of modules with version and path info, application crash specific information, memory region names with attribution and boundaries:

// from .crash reports

0x108f99000 - 0x109044ff7 (198.4 - 198) <7244D36E-4563-3E42-BA46-1F279D30A6CE> /Applications/Font Book

Exception Codes: 0x0000000000000001, 0x0000000000000000

Application Specific Information:
objc[195]: garbage collection is OFF
*** error for object 0x7fd7fb818e08: incorrect checksum for freed object - object was probably modified after being freed.

// from vmmap logs

==== Writable regions for process 966
Stack 0000000101f71000-0000000101ff3000 [ 520K] rw-/rwx SM=PRV thread 1
MALLOC_LARGE 0000000103998000-00000001039b8000 [ 128K] rw-/rwx SM=PRV DefaultMallocZone_0x101e6e000
MALLOC_SMALL (freed) 00000001039b9000-00000001039bb000 [ 8K] rw-/rwx SM=PRV
mapped file 0000000103a05000-0000000103f32000 [ 5300K] rw-/rwx SM=COW
mapped file 0000000104409000-00000001046d2000 [ 2852K] rw-/rwx SM=COW /System/Library/Fonts/Helvetica.dfont
MALLOC_LARGE 0000000104f6e000-0000000104f8e000 [ 128K] rw-/rwx SM=PRV DefaultMallocZone_0x101e6e000
MALLOC_LARGE (freed) 0000000108413000-0000000108540000 [ 1204K] rw-/rwx SM=COW
MALLOC_LARGE (freed) 0000000108540000-0000000108541000 [ 4K] rw-/rwx SM=PRV
MALLOC_TINY 00007fefe0c00000-00007fefe0d00000 [ 1024K] rw-/rwx SM=COW DefaultMallocZone_0x101e6e000
MALLOC_TINY 00007fefe0d00000-00007fefe0e00000 [ 1024K] rw-/rwx SM=PRV DispatchContinuations_0x101f38000
MALLOC_TINY 00007fefe0e00000-00007fefe0f00000 [ 1024K] rw-/rwx SM=COW DefaultMallocZone_0x101e6e000
MALLOC_SMALL 00007fefe1000000-00007fefe107b000 [ 492K] rw-/rwx SM=ZER DefaultMallocZone_0x101e6e000
MALLOC_SMALL 00007fefe107b000-00007fefe1083000 [ 32K] rw-/rwx SM=PRV DefaultMallocZone_0x101e6e000
MALLOC_SMALL 00007fefe1083000-00007fefe1149000 [ 792K] rw-/rwx SM=ZER DefaultMallocZone_0x101e6e000
MALLOC_SMALL (freed) 00007fefe1149000-00007fefe1166000 [ 116K] rw-/rwx SM=PRV DefaultMallocZone_0x101e6e000
MALLOC_SMALL (freed) 00007fefe1166000-00007fefe1800000 [ 6760K] rw-/rwx SM=ZER DefaultMallocZone_0x101e6e000
MALLOC_SMALL 00007fefe1800000-00007fefe18ff000 [ 1020K] rw-/rwx SM=ZER DefaultMallocZone_0x101e6e000
MALLOC_SMALL (freed) 00007fefe18ff000-00007fefe1901000 [ 8K] rw-/rwx SM=PRV DefaultMallocZone_0x101e6e000
MALLOC_SMALL 00007fefe1901000-00007fefe2000000 [ 7164K] rw-/rwx SM=ZER DefaultMallocZone_0x101e6e000
MALLOC_TINY (freed) 00007fefe2000000-00007fefe2100000 [ 1024K] rw-/rwx SM=PRV DispatchContinuations_0x101f38000
MALLOC_TINY 00007fefe2100000-00007fefe2200000 [ 1024K] rw-/rwx SM=PRV DefaultMallocZone_0x101e6e000
Stack 00007fff61186000-00007fff61985000 [ 8188K] rw-/rwx SM=ZER thread 0
Stack 00007fff61985000-00007fff61986000 [ 4K] rw-/rwx SM=COW

- Dmitry Vostokov @ + -

Forthcoming Training: Accelerated Mac OS X Core Dump Analysis

One Response to “Crash Dump Analysis Patterns (Part 180, Mac OS X)”

  1. Dmitry Vostokov Says:

    An example from managed space:

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