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Unhandled exception at 0x00007FF836A36FB1 (xul.dll) in firefox.exe: 0xC0000005: Access violation reading location 0x0000029F7A02DFDC.

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  • Last reply by FredMcD

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Hi Mozilla,

I am experiencing repeated crashes when opening Firefox (both standard and developer versions). The crash happens within 30 seconds of opening Firefox. The behavior just before the crash involves a slight hang, and then a crash.

I am able to debug with Visual Studio, and can see the following error message: Unhandled exception at 0x00007FF836A36FB1 (xul.dll) in firefox.exe: 0xC0000005: Access violation reading location 0x0000029F7A02DFDC.

I have tried many, many avenues, including: - Freshly reinstalling Windows 10 Enterprise - Running Firefox as Admin - Starting Firefox in Safe Mode - Refreshing Firefox - Reinstalling Firefox - Disabling/Enabling hw acceleration - Running a malware scan - Installing all necessary Windows updates

If I have some time, I will likely get the latest source and run it locally in debug. However, I am a C# dev, and not a C++ dev, so it may not be all that helpful.

Firefox Details: v62.0

PC Details: i7-7700K GTX 1080 16GB DDR4 @ 3200 Samsung Evo 960 EVO

The Firefox AppData folder is empty, and I am unable to find a proper crash report for you, but I do have a disassembly from Visual Studio. It seems to be crashing in _sk_gather_bgra_hsw().

Any help would be greatly appreciated!

Please let me know if you need any further info.

Cheers, Keagan

Disassembly info:

Unhandled exception at 0x00007FF836A36FB1 (xul.dll) in firefox.exe: 0xC0000005: Access violation reading location 0x0000029F7A02DFDC.

Breakpoint: 00007FF8222A2FB1 vpgatherdd ymm8,dword ptr [r8+ymm0*4],ymm3

DISASSEMBLY (Address: _sk_gather_bgra_hsw()):

00007FF8222A2F07  ?? ?? 00007FF8222A2F08  ?? ?? 00007FF8222A2F09  ?? ?? 00007FF8222A2F0A  ?? ?? 00007FF8222A2F0B  ?? ?? 00007FF8222A2F0C  ?? ?? 00007FF8222A2F0D  ?? ?? 00007FF8222A2F0E  ?? ?? 00007FF8222A2F0F  ?? ?? 00007FF8222A2F10  ?? ?? 00007FF8222A2F11  ?? ?? 00007FF8222A2F12  ?? ?? 00007FF8222A2F13  ?? ?? 00007FF8222A2F14  ?? ?? 00007FF8222A2F15  ?? ?? 00007FF8222A2F16  ?? ?? 00007FF8222A2F17  ?? ?? 00007FF8222A2F18  ?? ?? 00007FF8222A2F19  ?? ?? 00007FF8222A2F1A  ?? ?? 00007FF8222A2F1B  ?? ?? 00007FF8222A2F1C  ?? ?? 00007FF8222A2F1D  ?? ?? 00007FF8222A2F1E  ?? ?? 00007FF8222A2F1F  ?? ?? 00007FF8222A2F20  ?? ?? 00007FF8222A2F21  ?? ?? 00007FF8222A2F22  ?? ?? 00007FF8222A2F23  ?? ?? 00007FF8222A2F24  ?? ?? 00007FF8222A2F25  ?? ?? 00007FF8222A2F26  ?? ?? 00007FF8222A2F27  ?? ?? 00007FF8222A2F28  ?? ?? 00007FF8222A2F29  ?? ?? 00007FF8222A2F2A  ?? ?? 00007FF8222A2F2B  ?? ?? 00007FF8222A2F2C  ?? ?? 00007FF8222A2F2D  ?? ?? 00007FF8222A2F2E  ?? ?? 00007FF8222A2F2F  ?? ?? 00007FF8222A2F30  ?? ?? 00007FF8222A2F31  ?? ?? 00007FF8222A2F32  ?? ?? 00007FF8222A2F33  ?? ?? 00007FF8222A2F34  ?? ?? 00007FF8222A2F35  ?? ?? 00007FF8222A2F36  ?? ?? 00007FF8222A2F37  ?? ?? 00007FF8222A2F38  ?? ?? 00007FF8222A2F39  ?? ?? 00007FF8222A2F3A  ?? ?? 00007FF8222A2F3B  ?? ?? 00007FF8222A2F3C  ?? ?? 00007FF8222A2F3D  ?? ?? 00007FF8222A2F3E  ?? ?? 00007FF8222A2F3F  ?? ?? 00007FF8222A2F40  ?? ?? 00007FF8222A2F41  ?? ?? 00007FF8222A2F42  ?? ?? 00007FF8222A2F43  ?? ?? 00007FF8222A2F44  ?? ?? 00007FF8222A2F45  ?? ?? 00007FF8222A2F46  ?? ?? 00007FF8222A2F47  ?? ?? 00007FF8222A2F48  ?? ?? 00007FF8222A2F49  ?? ?? 00007FF8222A2F4A  ?? ?? 00007FF8222A2F4B  ?? ?? 00007FF8222A2F4C  ?? ?? 00007FF8222A2F4D  ?? ?? 00007FF8222A2F4E  ?? ?? 00007FF8222A2F4F  ?? ?? 00007FF8222A2F50  ?? ?? 00007FF8222A2F51  ?? ?? 00007FF8222A2F52  ?? ?? 00007FF8222A2F53  ?? ?? 00007FF8222A2F54  ?? ?? 00007FF8222A2F55  ?? ?? 00007FF8222A2F56  ?? ?? 00007FF8222A2F57  ?? ?? 00007FF8222A2F58  ?? ?? 00007FF8222A2F59  ?? ?? 00007FF8222A2F5A  ?? ?? 00007FF8222A2F5B  ?? ?? 00007FF8222A2F5C  ?? ?? 00007FF8222A2F5D  ?? ?? 00007FF8222A2F5E  ?? ?? 00007FF8222A2F5F  ?? ?? 00007FF8222A2F60 xabort 0FFh 00007FF8222A2F63 push qword ptr [rax+48FFFFFFh] 00007FF8222A2F69 lods dword ptr [rsi] 00007FF8222A2F6A vpbroadcastd ymm2,dword ptr [rax+0Ch] 00007FF8222A2F70 vpcmpeqd ymm3,ymm3,ymm3 00007FF8222A2F74 vpaddd ymm2,ymm2,ymm3 00007FF8222A2F78 vxorps ymm8,ymm8,ymm8 00007FF8222A2F7D vmaxps ymm0,ymm8,ymm0 00007FF8222A2F81 vminps ymm0,ymm0,ymm2 00007FF8222A2F85 vpbroadcastd ymm2,dword ptr [rax+10h] 00007FF8222A2F8B vpaddd ymm2,ymm2,ymm3 00007FF8222A2F8F vmaxps ymm1,ymm8,ymm1 00007FF8222A2F93 vminps ymm1,ymm1,ymm2 00007FF8222A2F97 mov r8,qword ptr [rax] 00007FF8222A2F9A vcvttps2dq ymm1,ymm1 00007FF8222A2F9E vpbroadcastd ymm2,dword ptr [rax+8] 00007FF8222A2FA4 vpmulld ymm1,ymm2,ymm1 00007FF8222A2FA9 vcvttps2dq ymm0,ymm0 00007FF8222A2FAD vpaddd ymm0,ymm1,ymm0 00007FF8222A2FB1 vpgatherdd ymm8,dword ptr [r8+ymm0*4],ymm3 00007FF8222A2FB7 vpand ymm0,ymm8,ymmword ptr [_sk_srcover_bgra_8888_sse2_lowp+788h (07FF8222D2FA0h)]

Hi Mozilla, I am experiencing repeated crashes when opening Firefox (both standard and developer versions). The crash happens within 30 seconds of opening Firefox. The behavior just before the crash involves a slight hang, and then a crash. I am able to debug with Visual Studio, and can see the following error message: Unhandled exception at 0x00007FF836A36FB1 (xul.dll) in firefox.exe: 0xC0000005: Access violation reading location 0x0000029F7A02DFDC. I have tried many, many avenues, including: - Freshly reinstalling Windows 10 Enterprise - Running Firefox as Admin - Starting Firefox in Safe Mode - Refreshing Firefox - Reinstalling Firefox - Disabling/Enabling hw acceleration - Running a malware scan - Installing all necessary Windows updates If I have some time, I will likely get the latest source and run it locally in debug. However, I am a C# dev, and not a C++ dev, so it may not be all that helpful. Firefox Details: v62.0 PC Details: i7-7700K GTX 1080 16GB DDR4 @ 3200 Samsung Evo 960 EVO The Firefox AppData folder is empty, and I am unable to find a proper crash report for you, but I do have a disassembly from Visual Studio. It seems to be crashing in _sk_gather_bgra_hsw(). Any help would be greatly appreciated! Please let me know if you need any further info. Cheers, Keagan Disassembly info: Unhandled exception at 0x00007FF836A36FB1 (xul.dll) in firefox.exe: 0xC0000005: Access violation reading location 0x0000029F7A02DFDC. Breakpoint: 00007FF8222A2FB1 vpgatherdd ymm8,dword ptr [r8+ymm0*4],ymm3 DISASSEMBLY (Address: _sk_gather_bgra_hsw()): 00007FF8222A2F07 ?? ?? 00007FF8222A2F08 ?? ?? 00007FF8222A2F09 ?? ?? 00007FF8222A2F0A ?? ?? 00007FF8222A2F0B ?? ?? 00007FF8222A2F0C ?? ?? 00007FF8222A2F0D ?? ?? 00007FF8222A2F0E ?? ?? 00007FF8222A2F0F ?? ?? 00007FF8222A2F10 ?? ?? 00007FF8222A2F11 ?? ?? 00007FF8222A2F12 ?? ?? 00007FF8222A2F13 ?? ?? 00007FF8222A2F14 ?? ?? 00007FF8222A2F15 ?? ?? 00007FF8222A2F16 ?? ?? 00007FF8222A2F17 ?? ?? 00007FF8222A2F18 ?? ?? 00007FF8222A2F19 ?? ?? 00007FF8222A2F1A ?? ?? 00007FF8222A2F1B ?? ?? 00007FF8222A2F1C ?? ?? 00007FF8222A2F1D ?? ?? 00007FF8222A2F1E ?? ?? 00007FF8222A2F1F ?? ?? 00007FF8222A2F20 ?? ?? 00007FF8222A2F21 ?? ?? 00007FF8222A2F22 ?? ?? 00007FF8222A2F23 ?? ?? 00007FF8222A2F24 ?? ?? 00007FF8222A2F25 ?? ?? 00007FF8222A2F26 ?? ?? 00007FF8222A2F27 ?? ?? 00007FF8222A2F28 ?? ?? 00007FF8222A2F29 ?? ?? 00007FF8222A2F2A ?? ?? 00007FF8222A2F2B ?? ?? 00007FF8222A2F2C ?? ?? 00007FF8222A2F2D ?? ?? 00007FF8222A2F2E ?? ?? 00007FF8222A2F2F ?? ?? 00007FF8222A2F30 ?? ?? 00007FF8222A2F31 ?? ?? 00007FF8222A2F32 ?? ?? 00007FF8222A2F33 ?? ?? 00007FF8222A2F34 ?? ?? 00007FF8222A2F35 ?? ?? 00007FF8222A2F36 ?? ?? 00007FF8222A2F37 ?? ?? 00007FF8222A2F38 ?? ?? 00007FF8222A2F39 ?? ?? 00007FF8222A2F3A ?? ?? 00007FF8222A2F3B ?? ?? 00007FF8222A2F3C ?? ?? 00007FF8222A2F3D ?? ?? 00007FF8222A2F3E ?? ?? 00007FF8222A2F3F ?? ?? 00007FF8222A2F40 ?? ?? 00007FF8222A2F41 ?? ?? 00007FF8222A2F42 ?? ?? 00007FF8222A2F43 ?? ?? 00007FF8222A2F44 ?? ?? 00007FF8222A2F45 ?? ?? 00007FF8222A2F46 ?? ?? 00007FF8222A2F47 ?? ?? 00007FF8222A2F48 ?? ?? 00007FF8222A2F49 ?? ?? 00007FF8222A2F4A ?? ?? 00007FF8222A2F4B ?? ?? 00007FF8222A2F4C ?? ?? 00007FF8222A2F4D ?? ?? 00007FF8222A2F4E ?? ?? 00007FF8222A2F4F ?? ?? 00007FF8222A2F50 ?? ?? 00007FF8222A2F51 ?? ?? 00007FF8222A2F52 ?? ?? 00007FF8222A2F53 ?? ?? 00007FF8222A2F54 ?? ?? 00007FF8222A2F55 ?? ?? 00007FF8222A2F56 ?? ?? 00007FF8222A2F57 ?? ?? 00007FF8222A2F58 ?? ?? 00007FF8222A2F59 ?? ?? 00007FF8222A2F5A ?? ?? 00007FF8222A2F5B ?? ?? 00007FF8222A2F5C ?? ?? 00007FF8222A2F5D ?? ?? 00007FF8222A2F5E ?? ?? 00007FF8222A2F5F ?? ?? 00007FF8222A2F60 xabort 0FFh 00007FF8222A2F63 push qword ptr [rax+48FFFFFFh] 00007FF8222A2F69 lods dword ptr [rsi] 00007FF8222A2F6A vpbroadcastd ymm2,dword ptr [rax+0Ch] 00007FF8222A2F70 vpcmpeqd ymm3,ymm3,ymm3 00007FF8222A2F74 vpaddd ymm2,ymm2,ymm3 00007FF8222A2F78 vxorps ymm8,ymm8,ymm8 00007FF8222A2F7D vmaxps ymm0,ymm8,ymm0 00007FF8222A2F81 vminps ymm0,ymm0,ymm2 00007FF8222A2F85 vpbroadcastd ymm2,dword ptr [rax+10h] 00007FF8222A2F8B vpaddd ymm2,ymm2,ymm3 00007FF8222A2F8F vmaxps ymm1,ymm8,ymm1 00007FF8222A2F93 vminps ymm1,ymm1,ymm2 00007FF8222A2F97 mov r8,qword ptr [rax] 00007FF8222A2F9A vcvttps2dq ymm1,ymm1 00007FF8222A2F9E vpbroadcastd ymm2,dword ptr [rax+8] 00007FF8222A2FA4 vpmulld ymm1,ymm2,ymm1 00007FF8222A2FA9 vcvttps2dq ymm0,ymm0 00007FF8222A2FAD vpaddd ymm0,ymm1,ymm0 00007FF8222A2FB1 vpgatherdd ymm8,dword ptr [r8+ymm0*4],ymm3 00007FF8222A2FB7 vpand ymm0,ymm8,ymmword ptr [_sk_srcover_bgra_8888_sse2_lowp+788h (07FF8222D2FA0h)]

Chosen solution

I have found the issue!

I can safely say that the issue is caused by a failing CPU! I inserted another CPU (i5-7600K) and booted up. Firefox worked flawlessly!

Thanks for your help guys. This is officially the only thread on the internet that links this error with a potential CPU failure. May help somebody, somewhere.

Cheers, K

Read this answer in context 👍 0

All Replies (13)

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Sorry to hear having issues make sure to include the bp-

The crash report is several pages of data. We need the report numbers to see the whole report.

  1. Enter about:crashes in the Firefox address bar and press Enter. A Submitted Crash Reports list will appear, similar to the one shown below.
  2. Copy the 5 most recent Report IDs that start with bp- and then go back to your forum question and paste those IDs into the "Post a Reply" box.

Note: If a recent Report ID does not start with bp- click on it to submit the report.

(Please don't take a screenshot of your crashes, just copy and paste the IDs. The below image is just an example of what your Firefox screen should look like.)

aboutcrashesFx57

Thank you for your help!

More information and further troubleshooting steps can be found in the Troubleshoot Firefox crashes (closing or quitting unexpectedly) article.

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Since you have no crash report try crashing it to get one.

You have tried all those things already. Something is causing Firefox to crash. With out the report it is beyond me in VB.

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I have managed to weasel the crash reports out (took around 50 crashes to get the 4 submitted).

Id's as requested:

bp-54a919bb-a6be-4d12-ba45-a2efc0180906 7/09/2018 9:31 AM bp-ceb05cd8-d8d8-4b33-8487-f7d990180906 7/09/2018 9:31 AM bp-d6f5182a-73a8-473d-a654-cb4390180906 7/09/2018 9:31 AM bp-fa487b25-5abf-4b02-83ce-fbe7b0180906 7/09/2018 9:30 AM

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The #5 crash (EnterBaseline) is a generic signature for any crash that happens in the JIT. https://groups.google.com/forum/#!topic/mozilla.dev.tech.js-engine.internals/dUlUxYsFz5Q

Too much for me. Someone will be along.

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HI, where are you and is this your correct date/Time ? 7/09/2018 9:31 AM

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Pkshadow said

HI, where are you and is this your correct date/Time ? 7/09/2018 9:31 AM

Yes, I am in New Zealand (UTC+1200) :)

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FredMcD said

Perform a System File Check to fix corrupted system files Win 7, 8, 10, Vista: https://support.microsoft.com/en-us/kb/929833 Win XP: https://answers.microsoft.com/en-us/windows/forum/all/windows-xp-scan-and-fix-disk-errors/6fe2827a-4be6-4bc1-8083-5139b5aa3a3d Wiki - Windows 10 System File Check http://answers.microsoft.com/en-us/windows/wiki/windows_10-update/system-file-check-sfc-scan-and-repair-system-files/bc609315-da1f-4775-812c-695b60477a93

I have performed the necessary steps outlined in the article - found no irregularities and still getting the crashing issue.

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Please try : 1) Use the Windows key + X keyboard shortcut to open the Power User menu and select Command Prompt (Admin). 2) Type or Copy/Paste the following command and press Enter: 3) DISM /Online /Cleanup-Image /RestoreHealth 4) Reboot

Then try : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

Reinstall with Current Release Firefox 62.0.0 with a Full Version Installer

Please let us know if this solved your issue or if need further assistance.

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Pkshadow said

Please try : 1) Use the Windows key + X keyboard shortcut to open the Power User menu and select Command Prompt (Admin). 2) Type or Copy/Paste the following command and press Enter: 3) DISM /Online /Cleanup-Image /RestoreHealth 4) Reboot Then try : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do : Reinstall with Current Release Firefox 62.0.0 with a Full Version Installer Please let us know if this solved your issue or if need further assistance.

I have followed the steps outlined above. It seems all English x64 builds are corrupt. This led me to install an x86 version... I occasionally get tab crashes now, but these are caught and dealt with appropriately (without killing the firefox process).

This can be seen in the following crash report: bp-0821454e-bfea-4747-bbd7-dba430180907

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Signature js::DecompressStringChunk

Hi, so the problem is still with js which is beyond me.

Could it be your connection/network driver or Firewall A/V that is the issue ?

Issues come up with : Avast/AVG, Kaspersky, BitDefender, ESET & sometimes McAfee

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Chosen Solution

I have found the issue!

I can safely say that the issue is caused by a failing CPU! I inserted another CPU (i5-7600K) and booted up. Firefox worked flawlessly!

Thanks for your help guys. This is officially the only thread on the internet that links this error with a potential CPU failure. May help somebody, somewhere.

Cheers, K

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That was very good work. Well done.