[PATCH 0/6] Fix signal-unsafe logging

[Bryce Harrington]

On Fri, Apr 06, 2012 at 12:00:50PM -0700, Chase Douglas wrote:
> On 04/06/2012 11:25 AM, Chase Douglas wrote:
> > Because corruption can occur, I suggest this be applied to the 1.12
> > stable series as well. However, I don't know for sure that corruption is
> > occurring, so it's not a clear cut candidate.
> 
> So now that I have fixed this issue, I can't reproduce the crash I was
> seeing before. Under valgrind I don't see any bugs, and under the normal
> scenario I don't see crashes. The crash I was seeing before was
> occurring when I put 10 touches on a magic trackpad simultaneously,
> which would also have triggered the signal logging code paths fixed here.
> 
> My best guess at this point is that the signal context logging really
> was corrupting things in the process. If true, then this should
> definitely be applied to the 1.12 stable branch.
> 
> This is all preliminary, based on a few minutes of testing. I'll follow
> up after more people have tested it out.

Testing failed on pad_to_int32 (I guess?)

Testing pad_to_int32
Unlinking from front.
[mi] Increasing EQ size to 512 to prevent dropped events.
[mi] EQ overflowing.  Additional events will be discarded until existing
events are processed.

Backtrace:
0: ./input (0x40000000+0x4e6c7) [0x4004e6c7]
1: ./input (mieqEnqueue+0x223) [0x40048653]
... etc. ...
5: ./input (0x40000000+0x14855) [0x40014855]
[mi] EQ processing has resumed after 5969 dropped events.
[mi] This may be caused my a misbehaving driver monopolizing the
server's resources.
PASS: input
PASS: xtest
PASS: list
PASS: misc
PASS: fixes
PASS: xfree86
/bin/bash: line 5: 14823 Segmentation fault      (core dumped)
MALLOC_PERTURB_=15 ${dir}$tst
FAIL: touch
========================================================================
1 of 8 tests failed


Full output here (although stdout/stderr is a bit out of order):
  http://paste.ubuntu.com/917885/

Bryce