Public bug reported: With the 7.0 hwe kernel on 24.04 (and presumably also the 7.0 kernel on 26.04), amdgpu completely fails to init on the SolidRun HoneyComb LX2 (NXP LX2160A, arm64, ACPI), where the GPU endpoint is enumerated directly on the root bus of its segment (there is no root port device, so pdev->bus->self is NULL):
amdgpu 0004:01:00.0: BAR 0 [mem 0xa400000000-0xa40fffffff 64bit pref]: releasing amdgpu 0004:01:00.0: BAR 2 [mem 0xa410000000-0xa4101fffff 64bit pref]: releasing amdgpu 0004:01:00.0: sw_init of IP block <gmc_v8_0> failed -19 amdgpu 0004:01:00.0: amdgpu_device_ip_init failed amdgpu 0004:01:00.0: Fatal error during GPU init No error is logged because the resize path reports success; amdgpu then finds BAR0 IORESOURCE_UNSET and bails out with -ENODEV. Observed at runtime on Ubuntu's linux-hwe-7.0 (7.0.0-14, broken) vs linux-hwe-6.17 (working), but nothing here is distro-specific: Ubuntu carries this code unmodified, and the affected function is identical to current mainline. By source inspection the regression window is v6.18 (old code paths) to v6.19 (consolidation). See https://lkml.org/lkml/2026/7/5/502 for full description and patch. Workaround is to disable resizable BAR using amdgpu.rebar=0 ** Affects: linux-hwe-7.0 (Ubuntu) Importance: Undecided Status: New ** Also affects: linux-hwe-7.0 (Ubuntu) Importance: Undecided Status: New ** No longer affects: linux-restricted-modules-hwe-6.17 (Ubuntu) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2159596 Title: amdgpu fails to come up due to BAR issue when at PCIe root To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-hwe-7.0/+bug/2159596/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
