Public bug reported: Backport the arm-smmu-v3 kdump adoption series to avoid disrupting in-flight DMA when the crash kernel boots.
Without this series, the crash kernel can reset/reprogram the SMMU while DMA from the panicked kernel is still active. On the affected system this can show up in BMC Redfish CPER logs as PCIe poisoned TLP and completion-timeout events during kdump capture. The fix lets the crash kernel detect that it is booting under kdump, adopt the previous stream table, retain `CR0_SMMUEN` where needed, and defer attachment for devices whose live DMA mappings must not be disturbed during crash dump collection. Backported from: https://lore.kernel.org/linux-iommu/[email protected]/#t 1. `iommu/arm-smmu-v3: Add arm_smmu_kdump_adopt_strtab() for kdump` 2. `iommu/arm-smmu-v3: Implement is_attach_deferred() for kdump` 3. `iommu/arm-smmu-v3: Do not enable EVTQ/PRIQ interrupts in kdump kernel` 4. `iommu/arm-smmu-v3: Skip EVTQ/PRIQ setup in kdump kernel` 5. `iommu/arm-smmu-v3: Retain CR0_SMMUEN during kdump device reset` 6. `iommu/arm-smmu-v3: Skip RMR bypass for kdump adoption` 7. `iommu/arm-smmu-v3: Detect ARM_SMMU_OPT_KDUMP_ADOPT in probe()` ** Affects: linux-nvidia-7.0 (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2156531 Title: Backport the arm-smmu-v3 kdump adoption series To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-nvidia-7.0/+bug/2156531/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
