Open Bug 1599024 Opened 2 months ago Updated 2 months ago

Crash in [@ mozilla::ReadEntry]

Categories

(Toolkit :: General, defect, P3)

Unspecified
Windows 10
defect

Tracking

()

Tracking Status
firefox-esr68 --- unaffected
firefox70 --- unaffected
firefox71 --- unaffected
firefox72 --- fix-optional

People

(Reporter: gsvelto, Unassigned)

References

(Blocks 1 open bug, Regression)

Details

(Keywords: crash, regression)

Crash Data

This bug is for crash report bp-b63756ca-c2bc-4b0e-a7c1-0a0d90191124.

Top 10 frames of crashing thread:

0 xul.dll static class mozilla::Result<mozilla::Ok, nsresult> mozilla::ReadEntry toolkit/components/backgroundhangmonitor/HangDetails.cpp:553
1 xul.dll static class mozilla::Result<mozilla::HangDetails, nsresult> mozilla::ReadHangDetailsFromFile toolkit/components/backgroundhangmonitor/HangDetails.cpp:608
2 xul.dll nsresult mozilla::SubmitPersistedPermahangRunnable::Run toolkit/components/backgroundhangmonitor/HangDetails.cpp:697
3 xul.dll nsThread::ProcessNextEvent xpcom/threads/nsThread.cpp:1250
4 xul.dll NS_ProcessNextEvent xpcom/threads/nsThreadUtils.cpp:486
5 xul.dll mozilla::ipc::MessagePumpForNonMainThreads::Run ipc/glue/MessagePump.cpp:333
6 xul.dll void MessageLoop::RunHandler ipc/chromium/src/base/message_loop.cc:308
7 xul.dll MessageLoop::Run ipc/chromium/src/base/message_loop.cc:290
8 xul.dll static void nsThread::ThreadFunc xpcom/threads/nsThread.cpp:458
9 nss3.dll static void _PR_NativeRunThread nsprpub/pr/src/threads/combined/pruthr.c:399

These are crashes in the background hang monitor with crash reason:

MOZ_CRASH(Unsupported HangEntry type?)

There are 17 crashes (from 4 installations) in nightly 72 starting with buildid 20191123214900. In analyzing the backtrace, the regression may have been introduced by patch [1] to fix bug 1594577.

[1] https://hg.mozilla.org/mozilla-central/rev?node=eb8741186210

Blocks: clouseau
Flags: needinfo?(dothayer)
Regressed by: 1594577

To clarify - this will not affect anything other than Nightly, as the background hang monitor is not enabled on anything other than Nightly. (I am not familiar with whether the status-firefoxN flags are intended to be edited by anyone, so I'm not going to mess with that.)

Gabriele, if you personally ran into this, do you happen to still have the profile that caused it? I'm specifically interested in the last_permahang.bin file which ought to be in the root of the profile directory, if you have it.

I need to update the MOZ_CRASH("Unsupported HangEntry type?"); line to be a soft failure, but with 17 crashes this doesn't look like a randomly corrupted file, but more like a bug during the writing of the file.

Flags: needinfo?(dothayer) → needinfo?(gsvelto)

(In reply to Doug Thayer [:dthayer] from comment #2)

Gabriele, if you personally ran into this, do you happen to still have the profile that caused it? I'm specifically interested in the last_permahang.bin file which ought to be in the root of the profile directory, if you have it.

I found this during crash triage. The first crash has buildid 20191122214053 so this might be caused by a regression in that build.

I need to update the MOZ_CRASH("Unsupported HangEntry type?"); line to be a soft failure, but with 17 crashes this doesn't look like a randomly corrupted file, but more like a bug during the writing of the file.

From what I can tell there's already four separate installations in the 25 crashes that have been reported. It's possible that a bug slipped in the writing or reading paths and the file is being either miswritten or misread?

Flags: needinfo?(gsvelto)

Giving this a priority to get it out of the triage queue, please adjust as necessary. If you know a better component then Firefox::General for this, please move it.

Priority: -- → P3
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