636918 - WebGL crash [@mozilla::gl::GLContext::fDeleteTextures]

Status: RESOLVED WONTFIX

(Core :: Graphics: CanvasWebGL, defect)

Description

[Christoph Diehl [:posidron]]

Attachment: testcase

Build identifier: Mozilla/5.0 (X11; Linux i686; rv:2.0b13pre) Gecko/20110223
Firefox/4.0b13pre
OpenGL vendor ('Tungsten Graphics, Inc') unrecognized

$ uname -r
2.6.35-24-generic-pae

$ lspci -v
00:02.0 VGA compatible controller: Intel Corporation Core Processor Integrated
Graphics Controller (rev 02) (prog-if 00 [VGA controller])
    Subsystem: Acer Incorporated [ALI] Device 040e
    Flags: bus master, fast devsel, latency 0, IRQ 43
    Memory at d0000000 (64-bit, non-prefetchable) [size=4M]
    Memory at c0000000 (64-bit, prefetchable) [size=256M]
    I/O ports at 3050 [size=8]
    Expansion ROM at <unassigned> [disabled]
    Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-
    Capabilities: [d0] Power Management version 2
    Capabilities: [a4] PCI Advanced Features
    Kernel driver in use: i915
    Kernel modules: i915

$ modinfo i915
filename:      
/lib/modules/2.6.35-24-generic-pae/kernel/drivers/gpu/drm/i915/i915.ko
license:        GPL and additional rights
description:    Intel Graphics
author:         Tungsten Graphics, Inc.
license:        GPL and additional rights
srcversion:     D34C2E6E5CC7885CFC640FC
depends:        drm,drm_kms_helper,video,intel-agp,i2c-algo-bit
vermagic:       2.6.35-24-generic-pae SMP mod_unload modversions 686

This graphic card is on the blacklist, but I wanted to test my fuzzer
on a Linux box and I only have one. Perhaps this bug is also reproducible in
other (Linux) environments.

Comment 1

[Christoph Diehl [:posidron]]

Attachment: callstack

Comment 2

[Benoit Jacob [:bjacob] (mostly away)]

This is almost certainly
   https://bugs.freedesktop.org/show_bug.cgi?id=33623

'wontfix' as this is a blacklisted driver anyways.

If you have time, it's certainly useful to report these driver bugs directly to freedesktop.org. The above linked bug shows how to extract as much information as possible from this kind of crashes. Basically:
  1) (obvious) get symbols for the driver, to get a better call stack
  2) use a debug build of firefox with MOZ_GL_DEBUG=1. For crashes at context creation, also use MOZ_X_SYNC=1.
  3) (doable even with a release build) once you get a crash, in GDB, in the stack trace, go to the first frame in gecko (libxul.so) and do:
    print DumpJSStack()
That gives you a javascript stack trace, very useful to understand what user code causes the crash.