Crash when choosing cycles device with python #81520

New Issue

Cedar Myers · 2020-10-07T20:35:17+02:00

Cedar Myers commented

2020-10-07 20:35:17 +02:00

System Information
Operating system: Ubuntu 20.04.1 LTS
Graphics card: GTX 1070 + GTX 1070 + GTX 1050 Ti, NVIDIA 440.100

Blender Version
Broken: 2.90.1, Commit date: 2020-09-23 06:43, Hash 3e85bb34d0
Worked: 2.83.7

Short description of error
Blender crashes when using python to choose CUDA GPU for cycles. I don't know if this happens in systems with only 1 GPU.

Exact steps for others to reproduce the error
Run Blender from command line with python expression to select GPU:

blender --factory-startup --python-expr "import bpy; cuda_devices, opencl_devices = bpy.context.preferences.addons['cycles'].preferences.get_devices(); cuda_devices[0].use = True"

More information:
Using get_devices_for_type() instead of get_devices() does not crash.

blender --factory-startup --python-expr "import bpy; cuda_devices = bpy.context.preferences.addons['cycles'].preferences.get_devices_for_type('CUDA'); cuda_devices[0].use = True"

The specific sequence of device types used by get_devices() matters, CUDA, then OPTIX, then OPENCL. Changing the sequence to CUDA last does not crash. Something about OPTIX and OPENCL mutates the CUDA devices. See the dump of cuda_devices before and after getting OPENCL devices:

blender --factory-startup --python-expr "import bpy; \
cuda_devices = bpy.context.preferences.addons['cycles'].preferences.get_devices_for_type('CUDA'); \
optix_devices = bpy.context.preferences.addons['cycles'].preferences.get_devices_for_type('OPTIX'); \
print('CUDA devices before getting OPENCL devices', cuda_devices); \
opencl_devices = bpy.context.preferences.addons['cycles'].preferences.get_devices_for_type('OPENCL'); \
print('CUDA devices after getting OPENCL devices', cuda_devices); \
print('OPTIX devices', optix_devices); \
print('OPENCL devices', opencl_devices); \
cuda_devices[0].use = True"

CUDA devices before getting OPENCL devices [<bpy_struct, CyclesDeviceSettings("GeForce GTX 1070")>, <bpy_struct, CyclesDeviceSettings("GeForce GTX 1070")>, <bpy_struct, CyclesDeviceSettings("GeForce GTX 1050 Ti")>, <bpy_struct, CyclesDeviceSettings("AMD Ryzen 9 3900X 12-Core Processor")>]
CUDA devices after getting OPENCL devices [<bpy_struct, CyclesDeviceSettings("")>, <bpy_struct, CyclesDeviceSettings("")>, <bpy_struct, CyclesDeviceSettings("")>, <bpy_struct, CyclesDeviceSettings("")>]
OPTIX devices [<bpy_struct, CyclesDeviceSettings("GeForce GTX 1070")>, <bpy_struct, CyclesDeviceSettings("GeForce GTX 1070")>, <bpy_struct, CyclesDeviceSettings("GeForce GTX 1050 Ti")>]
OPENCL devices [<bpy_struct, CyclesDeviceSettings("AMD Ryzen 9 3900X 12-Core Processor")>]

Also, this seems to have something to do with OPTIX. Removing OPTIX from the sequence above also does not crash.

**System Information** Operating system: Ubuntu 20.04.1 LTS Graphics card: GTX 1070 + GTX 1070 + GTX 1050 Ti, NVIDIA 440.100 **Blender Version** Broken: 2.90.1, Commit date: 2020-09-23 06:43, Hash 3e85bb34d0d7 Worked: 2.83.7 **Short description of error** Blender crashes when using python to choose CUDA GPU for cycles. I don't know if this happens in systems with only 1 GPU. **Exact steps for others to reproduce the error** Run Blender from command line with python expression to select GPU: ``` blender --factory-startup --python-expr "import bpy; cuda_devices, opencl_devices = bpy.context.preferences.addons['cycles'].preferences.get_devices(); cuda_devices[0].use = True" ``` **More information:** Using get_devices_for_type() instead of get_devices() does not crash. ``` blender --factory-startup --python-expr "import bpy; cuda_devices = bpy.context.preferences.addons['cycles'].preferences.get_devices_for_type('CUDA'); cuda_devices[0].use = True" ``` The specific sequence of device types used by get_devices() matters, CUDA, then OPTIX, then OPENCL. Changing the sequence to CUDA last does not crash. Something about OPTIX and OPENCL mutates the CUDA devices. See the dump of cuda_devices before and after getting OPENCL devices: ``` blender --factory-startup --python-expr "import bpy; \ cuda_devices = bpy.context.preferences.addons['cycles'].preferences.get_devices_for_type('CUDA'); \ optix_devices = bpy.context.preferences.addons['cycles'].preferences.get_devices_for_type('OPTIX'); \ print('CUDA devices before getting OPENCL devices', cuda_devices); \ opencl_devices = bpy.context.preferences.addons['cycles'].preferences.get_devices_for_type('OPENCL'); \ print('CUDA devices after getting OPENCL devices', cuda_devices); \ print('OPTIX devices', optix_devices); \ print('OPENCL devices', opencl_devices); \ cuda_devices[0].use = True" CUDA devices before getting OPENCL devices [<bpy_struct, CyclesDeviceSettings("GeForce GTX 1070")>, <bpy_struct, CyclesDeviceSettings("GeForce GTX 1070")>, <bpy_struct, CyclesDeviceSettings("GeForce GTX 1050 Ti")>, <bpy_struct, CyclesDeviceSettings("AMD Ryzen 9 3900X 12-Core Processor")>] CUDA devices after getting OPENCL devices [<bpy_struct, CyclesDeviceSettings("")>, <bpy_struct, CyclesDeviceSettings("")>, <bpy_struct, CyclesDeviceSettings("")>, <bpy_struct, CyclesDeviceSettings("")>] OPTIX devices [<bpy_struct, CyclesDeviceSettings("GeForce GTX 1070")>, <bpy_struct, CyclesDeviceSettings("GeForce GTX 1070")>, <bpy_struct, CyclesDeviceSettings("GeForce GTX 1050 Ti")>] OPENCL devices [<bpy_struct, CyclesDeviceSettings("AMD Ryzen 9 3900X 12-Core Processor")>] ``` Also, this seems to have something to do with OPTIX. Removing OPTIX from the sequence above also does not crash.

Cedar Myers commented

2020-10-07 20:35:17 +02:00

Added subscriber: @Cedar-Myers

Robert Guetzkow commented

2020-10-07 22:41:01 +02:00

Added subscriber: @rjg

Robert Guetzkow commented

2020-10-07 22:41:01 +02:00

Changed status from 'Needs Triage' to: 'Needs User Info'

Robert Guetzkow commented

2020-10-07 22:41:01 +02:00

I can't reproduce this on my one GPU system. Could you run Blender from the terminal with ./blender --debug --debug-python --debug-gpu > ~/blender_debug_output.txt 2>&1 and upload the output as well as the crash log / stack trace?

I can't reproduce this on my one GPU system. Could you run Blender from the terminal with `./blender --debug --debug-python --debug-gpu > ~/blender_debug_output.txt 2>&1` and upload the output as well as the crash log / stack trace?

Cedar Myers commented

2020-10-08 00:21:32 +02:00

These are pretty short. Do I need a certain build for debugging?

blender.crash.txt

blender_debug_output.txt

These are pretty short. Do I need a certain build for debugging? [blender.crash.txt](https://archive.blender.org/developer/F8965899/blender.crash.txt) [blender_debug_output.txt](https://archive.blender.org/developer/F8965900/blender_debug_output.txt)

Robert Guetzkow commented

2020-10-08 00:37:18 +02:00

Changed status from 'Needs User Info' to: 'Needs Triage'

Robert Guetzkow commented

2020-10-08 00:39:52 +02:00

@Cedar-Myers No, the log files are exactly how they are supposed to be.

Raimund Klink commented

2020-10-08 08:22:53 +02:00

Added subscriber: @Raimund58

blender-admin commented

2020-10-15 07:51:18 +02:00

This issue was referenced by 0ff7d21c27

This issue was referenced by 0ff7d21c27957b4f4a9f02c59b458cdd6beeb06b

blender-admin commented

2020-10-15 07:51:18 +02:00

This issue was referenced by 1001adb500

This issue was referenced by 1001adb500196537050cc60e8d80318a2f1a56c3

Campbell Barton commented

2020-10-15 07:54:06 +02:00

Changed status from 'Needs Triage' to: 'Resolved'

Campbell Barton closed this issue

2020-10-15 07:54:06 +02:00

Campbell Barton self-assigned this 2020-10-15 07:54:06 +02:00

Cedar Myers commented

2020-10-19 21:00:31 +02:00

I have tested the 2.91.0-3bc808ebcbf6 nightly build and I can confirm that this fixes get_devices() but get_devices_for_type() still suffers the same problem when called in sequence (CUDA, then OPTIX, then OPENCL). Should this be filed as a new issue, or should this issue be re-opened?

Also, I'm uncertain if this is relevant for LTS backport since 2.83 does not crash, but I'll leave that to you guys to determine.

I have tested the 2.91.0-3bc808ebcbf6 nightly build and I can confirm that this fixes get_devices() but get_devices_for_type() still suffers the same problem when called in sequence (CUDA, then OPTIX, then OPENCL). Should this be filed as a new issue, or should this issue be re-opened? Also, I'm uncertain if this is relevant for LTS backport since 2.83 does not crash, but I'll leave that to you guys to determine.

Robert Guetzkow commented

2020-10-19 22:15:45 +02:00

@Cedar-Myers Since this ticket as already been closed with an associated commit, it's probably a good idea to open another ticket. Just to make sure it's not forgotten.

Campbell Barton commented

2020-10-20 03:17:42 +02:00

@Cedar-Myers other issues should be reported separately, get_devices_for_type is returning data that's re-allocated, so we'll need to copy the return values to prevent problems like this from happening entirely.

@Cedar-Myers other issues should be reported separately, `get_devices_for_type` is returning data that's re-allocated, so we'll need to copy the return values to prevent problems like this from happening entirely.

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Crash when choosing cycles device with python #81520