722226 - periodic firefox hanging

Status: RESOLVED INCOMPLETE

(Core :: JavaScript Engine, defect)

Description

[:glob ✱]

Attachment: thread backtrace

i've been seeing periodic hangs of nightly.

i've attached a backtrace of all threads during a hang; roc indicated that thread 28 looks guilty:

Thread 28 (process 80914):
#0  0x00007fff89667e4a in memmove$VARIANT$sse42 ()
#1  0x0000000102264eb6 in js::crash::Ring::push ()


Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:12.0a1) Gecko/20120129 Firefox/12.0a1

Comment 1

[:glob ✱]

Attachment: another set of backtraces

after another hang, here's another set of backtraces (i won't do anymore unless requested).

includes:

Thread 21 (process 96809):
#0  0x00007fff89667e73 in memmove$VARIANT$sse42 ()
#1  0x0000000102264f96 in js::crash::Ring::push ()

Comment 2

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

When did this start happening? Is it only on a particular site, or just general browsing? Were you visiting sites using web workers (that you know of)?

Also, how did you capture the stack trace? In both threads, breakpad appears to be running. Maybe that's just a symptom of how you captured the stacks, though.

js::crash::Ring::push doesn't really do anything itself besides call memcpy. It's only called at the beginning of a GC. So it's weird that we even end up there on something that's not the main thread. And even if we do, it shouldn't hang there.

Comment 3

[:glob ✱]

(In reply to Bill McCloskey (:billm) from comment #2)
> When did this start happening?

one to two weeks ago (i think, sorry).

> Is it only on a particular site, or just general browsing?

general browsing; sometimes overnight.

> Were you visiting sites using web workers (that you know of)?

i don't know.

> Also, how did you capture the stack trace? In both threads, breakpad appears
> to be running. Maybe that's just a symptom of how you captured the stacks,
> though.

attached with gdb, then 'thread apply all bt'.

Comment 4

[Mayank Bansal]

This is an old bug with no updated info.
Glob, I will close this bug but please reopen if you can still repro.
Thanks!