[Bug 2158605] Re: The screen will show garbages by running glxgears fullscreen.

** Tags added: jira-stella-3470 oem-priority -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2158605 Title: The screen will show garbages by running glxgears fullscreen. Status in OEM Priority Project: New Status in linux package in Ubuntu: Invalid Status in linux-oem-6.17 package in Ubuntu: New Status in linux source package in Noble: Invalid Status in linux-oem-6.17 source package in Noble: Fix Committed Status in linux source package in Resolute: In Progress Status in linux-oem-6.17 source package in Resolute: Invalid Bug description: BugLink: https://bugs.launchpad.net/bugs/2158605 [Impact] Screen garbage can show when running glxgears fullscreen on affected Intel graphics systems. The Launchpad report says it happens about 1 in 3 runs. [Fix] Skip the SCANOUT flag and VM_BIND checks for external dma-buf imports in the xe display framebuffer setup and pin paths. For imported sg buffers, CPU caching is controlled by the exporter. The patch keeps the existing checks for local buffers. This patch is from upstream Patchwork, not yet merged: https://patchwork.freedesktop.org/patch/732636/ [Test Plan] Run the fullscreen glxgears test 10 times: $ glxgears -fullscreen Or run the matching checkbox test for the affected GPU: $ checkbox-cli run graphics/2_valid_glxgears_fullscreen_PCI_ID_<affected-gpu> Without patch: screen shows garbage during the fullscreen glxgears test. With patch: fullscreen glxgears completes without screen garbage. [Where problems could occur] Could break external dma-buf framebuffer setup in the xe display driver. If the sg-buffer exception is wrong, imported framebuffers could be accepted when they should be rejected. This could show as display corruption, failed framebuffer creation, or xe framebuffer pinning warnings. [Other Info] SRU target: linux-oem-6.17. The patch is not in an upstream kernel release yet. To manage notifications about this bug go to: https://bugs.launchpad.net/oem-priority/+bug/2158605/+subscriptions