On 30/11/15 11:45, Greg Kurz wrote: > Since commit 1d2d974244c6 "spapr_pci: enumerate and add PCI device tree", QEMU > populates the PCI device tree in the opposite order compared to SLOF. > > Before 1d2d974244c6: > > Populating /pci@800000020000000 > 00 0000 (D) : 1af4 1000 virtio [ net ] > 00 0800 (D) : 1af4 1001 virtio [ block ] > 00 1000 (D) : 1af4 1009 virtio [ network ] > Populating /pci@800000020000000/unknown-legacy-device@2 > > > 7e5294b8 : /pci@800000020000000 > 7e52b998 : |-- ethernet@0 > 7e52c0c8 : |-- scsi@1 > 7e52c7e8 : +-- unknown-legacy-device@2 ok > > Since 1d2d974244c6: > > Populating /pci@800000020000000 > 00 1000 (D) : 1af4 1009 virtio [ network ] > Populating /pci@800000020000000/unknown-legacy-device@2 > 00 0800 (D) : 1af4 1001 virtio [ block ] > 00 0000 (D) : 1af4 1000 virtio [ net ] > > > 7e5e8118 : /pci@800000020000000 > 7e5ea6a0 : |-- unknown-legacy-device@2 > 7e5eadb8 : |-- scsi@1 > 7e5eb4d8 : +-- ethernet@0 ok > > This behaviour change is not actually a bug since no assumptions should be > made on DT ordering. But it has no real justification either, other than > being the consequence of the way fdt_add_subnode() inserts new elements > to the front of the FDT rather than adding them to the tail. > > This patch reverts to the historical SLOF ordering by walking PCI devices in > reverse order.
I've applied your patch here locally, and indeed, the device tree looks nicer to me, too, when the nodes are listed in ascending order. Tested-by: Thomas Huth <th...@redhat.com>
