On Tue, Jul 21, 2015 at 11:57 AM, Bjorn Helgaas <bhelgaas@xxxxxxxxxx> wrote: > On Mon, Jul 13, 2015 at 09:57:32AM -0500, Jordan Hargrave wrote: >> On Mon, Jul 13, 2015 at 2:35 AM, Jean Delvare <jdelvare@xxxxxxx> wrote: >> >> > Hi Jordan, >> > >> > On Fri, 10 Jul 2015 17:02:46 -0500, Jordan Hargrave wrote: >> > > From: Jordan Hargrave <Jordan_Hargrave@xxxxxxxx> >> > > >> > > There currently isn't an easy way to determine which PCI devices belong >> > to >> > > system slots. This patch adds support to read SMBIOS Type 9 (System >> > Slots). >> > >> > I'm wondering, can't you use dmidecode or libsmbios to retrieve the >> > same information? >> > >> > -- >> > Jean Delvare >> > SUSE L3 Support >> > >> >> You can but it's as not easy to determine the slot number for leaf devices >> on bridges. Eventually planning on using this for pulling slot number for >> identifying network cards and disk numbering for systemd > > Can you outline the problems with using dmidecode or libsmbios? Neither dmidecode nor libsmbios report the slot number for devices behind bridges in a slot. I'm wanting to use this sysfs variable to get slot numbers for systemd, so using libsmbios and dmidecode aren't very useful. We already report the index for embedded devices in pci-label.c, this code should have gone in at the same time. For example. The SMBIOS entry for slot 3 is 40:00.0 There is a quad-port NIC in the slot with a bridge at 40:00.0 42:00.0 Bridge (sec=43, sub=45) 43:02.0 Bridge (sec=44, sub=44) 43:04.0 Bridge (sec=45, sub=45) 44:00.0 Ethernet 44:00.1 Ethernet 45:00.0 Ethernet 45:00.1 Ethernet So dmidecode only returns the slot number for 42:00.0 but not any child devices. This code will provide a 'slot' sysfs variable that reports '3' for all devices under and including the bridge. -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
