[DCV] Fix Xdcv segfault on RHEL9 and Rocky9 caused by DCV attempting GL initialization when GPU acceleration is not supported.#3156
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Codecov Report✅ All modified and coverable lines are covered by tests. Additional details and impacted files@@ Coverage Diff @@
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himani2411
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Apr 10, 2026
| # second that are sent to the client. A higher value consumes more bandwidth | ||
| # and resources. By default it is set to 25. Set to 0 for no limit | ||
| #target-fps = 30 | ||
| <% unless node['cluster']['dcv']['is_graphic_instance'] %> |
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IS this an attribute we set, i cant find it being mentioned anywhere so we add these display-encodes for all instances regardless it is GPU or not? Or is this an ExtraChefAttribute?
himani2411
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Apr 10, 2026
| it { should be_mode 0755 } | ||
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| unless instance.graphic? && instance.nvidia_installed? && instance.dcv_gpu_accel_supported? | ||
| its('content') { should match /enable-gl-in-virtual-sessions\s*=\s*"always-off"/ } |
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Can you also add the check for display-encoders?
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Good catch! Addressed
…GL initialization even when GPU acceleration is not supported. To prevent Xdcv from segfaulting during GLX initialization, we disabled in dcv.conf the use of dcv-gl (parameter enable-gl-in-virtual-sessions) and hardware encoding (parameter display-encoders) for instances where GPU acceleration is not supported.
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Description of changes
Disable DCV-GL on instance types not supporting GPU acceleration.
Before this change we used to keep DCV-GL always-on in DCV configuration even for instance types not supporting GPIU acceleration, such as g5g. In certain OSs. This was causing intermittent failures in the setup of dcv connection
Fix Xdcv segfault on RHEL9 and Rocky9 caused by DCV attempting GL initialization when GPU acceleration is not supported. We did it by explicitly disabling dcv-gl in dcv.conf on instances where GPU acceleration is not supported, preventing Xdcv from segfaulting during GLX initialization. The fix is applied to all OSs, because it is correct to keep dcv-gl disabledeven if on other OSs it seems that
Tests
test_dcv_configurationexecuted on all OSsBy submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.