1441453 - Report the command line of a crashed process

Status: ASSIGNED

(Toolkit :: Crash Reporting, enhancement)

Description

[Steve Fink [:sfink] [:s:]]

When mozcrash.py runs, it generates PROCESS-CRASH output but I don't see anything in it that allows me to associate a crash with the program that ran. A pid would be enough to associate them, although having the command line immediately available would be more convenient.

Comment 1

[(not currently active) Ted Mielczarek]

mozcrash just runs minidump_stackwalk on the dump files, it doesn't know anything about processes. There is a PID in the dump file (at least on Windows, I'm not sure if other platforms fill that in), so we could ostensibly make minidump_stackwalk print that. Minidumps don't have the commandline information, though.

Comment 2

[Steve Fink [:sfink] [:s:]]

Yeah, sorry, I didn't meant to imply this was a mozcrash.py thing. I looked through minidump_stackwalk, and it seemed like it wanted to find some sort of MinidumpInfo struct with process information in it (I forget the exact name). My sample minidump appeared to not contain that data. I tried stepping through the crash dump generation to figure out when it might be emitted, but didn't have much luck and didn't want to spend a lot of time figuring it out. Especially if someone (likely a ted-shaped someone) happened to already know a simple solution.

Comment 3

[(not currently active) Ted Mielczarek]

Yeah, `MDRawMiscInfo` has a `process_id` field:
https://chromium.googlesource.com/breakpad/breakpad/+/6d0287851fabc21a90838ae068b11f2d777393d5/src/google_breakpad/common/minidump_format.h#785

...but the Linux client code doesn't write that info to minidumps. Since we use Microsoft's API on Windows we get it there, and the Mac client has code to write it (which probably wouldn't be hard to port to the Linux client):
https://dxr.mozilla.org/mozilla-central/rev/5297541590781af40ff09e067646f3115960af75/toolkit/crashreporter/breakpad-client/mac/handler/minidump_generator.cc#1528

Comment 4

[Steve Fink [:sfink] [:s:]]

(Yoshi, Jon: I guess I already filed a bug for this one. CC'ing.)

Comment 5

[(not currently active) Ted Mielczarek]

To expound on my earlier answer: dumps written by Breakpad on Linux do contain the raw contents of /proc/self/cmdline:
https://chromium.googlesource.com/breakpad/breakpad/+/6d0287851fabc21a90838ae068b11f2d777393d5/src/processor/minidump_dump.cc#192

Windows minidumps do apparently usually contain the commandline in the process environment block but you have to grovel around through poorly-documented structures to find it.

Comment 6

[Gabriele Svelto [:gsvelto]]

After bug 1487410 lands it should be rather easy to write out the PID into the stackwalker's JSON output and have mozcrash present it to the user

Comment 7

[Steve Fink [:sfink] [:s:]]

Attachment: Bug 1441453 - Display the linux command line if available

Comment 8

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/e04c792b53e3
Display the linux command line if available r=gsvelto

Comment 9

[Atila Butkovits]

Backed out for causing python failures.

Backout link: https://hg.mozilla.org/integration/autoland/rev/c526b3d6a76d508e67fa61483669605b4ed89f4b

Push with failures: https://treeherder.mozilla.org/jobs?repo=autoland&selectedTaskRun=KYflqrYYQHeA3OgCzAwQuw.0&resultStatus=testfailed%2Cbusted%2Cexception%2Cretry%2Cusercancel&revision=fcfa4c3423948d994cd65ec6e08dd0f5660402cc

Failure log: https://treeherder.mozilla.org/logviewer?job_id=370333881&repo=autoland&lineNumber=1055

Comment 10

[Cristian Tuns]

Backout merged to central: https://hg.mozilla.org/mozilla-central/rev/c526b3d6a76d

Comment 11

[Gabriele Svelto [:gsvelto]]

Changing the title here because we've been printing the PID of each crashed process in bug 1840651.