610380 - Expose exception information parameters

Status: NEW

(Socorro :: General, enhancement, P3)

Description

[Jeff Muizelaar [:jrmuizel]]

The exceptions recorded in minidumps contain some exception parameters that we're not exposing in Socorro.

Running minidump_dump on a minidump gives:

MDException
  thread_id                                  = 0x910
  exception_record.exception_code            = 0x879
  exception_record.exception_flags           = 0x0
  exception_record.exception_record          = 0x0
  exception_record.exception_address         = 0x760e9617
  exception_record.number_parameters         = 2
  exception_record.exception_information[ 0] = 0xffffffff887a0020
  exception_record.exception_information[ 1] = 0xffffffff8876017c
  thread_context.data_size                   = 716
  thread_context.rva                         = 0x7952

In this case the exception_record.exception_information contains the error code for the D3D error that is the cause of the crash.

This would help in debugging the crash we're seeing in bug 596431.

Comment 1

[(not currently active) Ted Mielczarek]

This is really hard to do right now, because the processor just runs "minidump_stackwalk -m" on the minidump, which uses an awful pipe-delimited text format, which is a pain in the ass to extend.

I filed bug 573100 a while ago to change it to instead output JSON, which would make life much easier.

Comment 2

[(not currently active) Ted Mielczarek]

This would be easy to do nowadays. Somewhere around here:
https://github.com/mozilla/socorro/blob/7d2713ea2e40463fd06edde0e9a27117acc7745c/minidump-stackwalk/stackwalker.cc#L1152

You'd do:
```
MinidumpException* exception = minidump.GetException();
if (exception) {
  MDRawExceptionStream* raw_exception = exception->exception();
}
```

Then you can pull arbitrary fields out of raw_exception:
https://code.google.com/p/google-breakpad/source/browse/trunk/src/google_breakpad/common/minidump_format.h#515

and stuff them in the JSON result object.

Comment 3

[Will Kahn-Greene [:willkg] ET needinfo? me]

Bumping this to a P2 to look into.

Comment 4

[Will Kahn-Greene [:willkg] ET needinfo? me]

Mark as enhancement.

Comment 5

[Will Kahn-Greene [:willkg] ET needinfo? me]

We're not going to get to this any time soon, so I'm bumping it down to P3.

Comment 6

[Will Kahn-Greene [:willkg] ET needinfo? me]

Gabriele: Is this bug relevant anymore? If so, I can write up a feature request in rust-minidump.

Comment 7

[Gabriele Svelto [:gsvelto]]

Yes! Thanks for pointing it out because we're not surfacing that information yet.

Comment 8

[Will Kahn-Greene [:willkg] ET needinfo? me]

rust-minidump issue: https://github.com/rust-minidump/rust-minidump/issues/1046

Once that's implemented in rust-minidump, we can figure out what's public/sensitive and how we want to expose it in Crash Stats.

Comment 9

[Gabriele Svelto [:gsvelto]]

(In reply to Will Kahn-Greene [:willkg] ET needinfo? me from comment #8)

Once that's implemented in rust-minidump, we can figure out what's public/sensitive and how we want to expose it in Crash Stats.

Thanks! This will probably be public because we already use the content of this field for certain exceptions (Windows stores the crash address or the error code there sometimes), so it's just a matter of surfacing it for a broader set of exceptions (and figure out how to display them).