1371454 - NVDA crashes when tabbing through bugzilla forms

Status: RESOLVED WORKSFORME

(Core :: Disability Access APIs, defect)

Description

[Jim Mathies [:jimm]]

STR:

1) start NVDA
2) Start Nightly
3) Open a Mozilla bugzilla bug like this one
4) use the tab key to move through the form elements quickly. (Using key releat helps)

result:
1) NVDA occasionally crashes, then restarts and recovers.
2) Firefox is unaffected by this

Comment 1

[James Teh [:Jamie]]

I do see problematic behaviour, but not an NVDA crash. For me, Firefox freezes and I have to kill it to usefully use my system.

If you're seeing an NVDA crash, it should generate a minidump in %temp%\nvda_crash.dmp. Our symbols are available via our symbol server: srv*http://www.nvaccess.org/files/nvda/symbols
Note that while we do upload some of the NVDA symbols to the Mozilla symbol server, we only upload the symbols that would get injected into Firefox's process, which won't be enough in this case.

Comment 2

[Jim Mathies [:jimm]]

(In reply to James Teh [:Jamie] from comment #1)
> I do see problematic behaviour, but not an NVDA crash. For me, Firefox
> freezes and I have to kill it to usefully use my system.

If you tested in latest Nightly, you may have run into bug 1371345 which was causing a lot of freezing. Should be fixed in Saturday's builds.

Comment 3

[Jim Mathies [:jimm]]

Hey Jamie, every time NVDA restarts, the log it generates is cleared (NVDA tray icon -> tools -> View Log). Is there a way to collect data or logs across sessions to try and figure out what's causing these crashes?

Comment 4

[Marco Zehe (:MarcoZ)]

Jim, look in your %temp% folder for nvda-old.log after NVDA restarted. That contains the log from the previous session.

Comment 5

[Marco Zehe (:MarcoZ)]

BTW I am seeing none of these crashes. NVDA runs with Firefox with E10S on without problems for me.

Comment 6

[Jim Mathies [:jimm]]

Attachment: nvda-old.log

Here's the old log, I also have a crash dump file saved.

Comment 7

[Jim Mathies [:jimm]]

Attachment: nvda stack

nvda stack - not very useful unfortunately.

Comment 8

[Jim Mathies [:jimm]]

(In reply to Marco Zehe (:MarcoZ) from comment #5)
> BTW I am seeing none of these crashes. NVDA runs with Firefox with E10S on
> without problems for me.

I'm using nvda + Nightly 64-bit. I open a bugzilla bug and tab focus through the form controls. When I get to text inputs that trigger drop downs, if I move away from those quickly, which seems to help trigger the crash.

Comment 9

[James Teh [:Jamie]]

I realise you're using 64 bit, but do you have the 32 bit smart proxy registered (e.g. because you also have 32 bit installed)? If so, that would suggest the smart proxy is being used. If that's true, is it based on the same version of Firefox?

It looks like NVDA is crashing when trying to call Release on a COM object. This happens while fetching the accessibles for row headers (from IAccessibleTableCell::rowHeaderCells). I can't be certain which pointer is being released because we let Python handle the releasing (based on reference counting/garbage collection), but it's very probably one of these row header cell accessibles. We aren't seeing any COM or Mozilla stuff in the stack, so that suggests we somehow had an invalid COM pointer (or it was somehow valid and got released already).

Comment 10

[Jim Mathies [:jimm]]

not seeing this anymore with nvda.