On 2025-01-30 06:12, Jan Beulich wrote:
In order for amd_iommu_detect_one_acpi()'s call to pci_ro_device() to have permanent effect, pci_segments_init() needs to be called ahead of making it there. Without this we're losing segment 0's r/o map, and thus we're losing write-protection of the PCI devices representing IOMMUs. Which in turn means that half-way recent Linux Dom0 will, as it boots, turn off MSI on these devices, thus preventing any IOMMU events (faults in particular) from being reported on pre-x2APIC hardware.As the acpi_iommu_init() invocation was moved ahead of acpi_mmcfg_init()'s by the offending commit, move the call to pci_segments_init() accordingly. Fixes: 3950f2485bbc ("x86/x2APIC: defer probe until after IOMMU ACPI table parsing") Signed-off-by: Jan Beulich <[email protected]>
Reviewed-by: Jason Andryuk <[email protected]> Tested-by: Jason Andryuk <[email protected]> Thanks, Jason
