On Mon, 21 Dec 2015 12:56:24 +1100 David Gibson <da...@gibson.dropbear.id.au> wrote:
> On Thu, Dec 17, 2015 at 09:43:29AM +0100, Greg Kurz wrote: > > On Thu, 3 Dec 2015 15:53:17 +0100 > > Greg Kurz <gk...@linux.vnet.ibm.com> wrote: > > > > > On Tue, 1 Dec 2015 22:48:38 +0100 > > > Thomas Huth <th...@redhat.com> wrote: > > > > > > > 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> > > > > > > > > > > > > > > > Ping ? > > Sorry I didn't reply. > > I'm still dubious about this. It seems like a fair bit of effort to > restore a behaviour that the client isn't supposed to be relying on > anyway. > > Plus, the version with the changed order is already released, so > applying this will mean a second behaviour change. > And since nobody apart from Thomas expressed interest, I guess it is not something people dearly want. Just forget about this patch. :) Cheers. -- Greg
