From 7af151ca282d506a8e409a68b656f6d1cd2f13fb Mon Sep 17 00:00:00 2001 From: Etienne Champetier Date: Tue, 9 Jul 2024 11:53:50 -0400 Subject: [PATCH] udev-builtin-net_id: use firmware_node/sun for ID_NET_NAME_SLOT pci_get_hotplug_slot() has the following limitations: - if slots are not hotpluggable, they are not in /sys/bus/pci/slots. - the address at /sys/bus/pci/slots/X/addr doesn't contains the function part, so on some system, 2 different slots with different _SUN end up with the same hotplug_slot, leading to naming conflicts. - it tries all parent devices until it finds a slot number, which is incorrect, and what led to NAMING_BRIDGE_MULTIFUNCTION_SLOT being disabled. The use of PCI hotplug to find the slot (ACPI _SUN) was introduced in https://github.com/systemd/systemd/commit/0035597a30d120f70df2dd7da3d6128fb8ba6051 "udev: net_id - export PCI hotplug slot names" on 2012/11/26. At the same time on the kernel side we got https://github.com/torvalds/linux/commit/bb74ac23b10820d8722c3e1f4add9ef59e703f63 "ACPI: create _SUN sysfs file" on 2012/11/16. Using PCI hotplug was the only way at the time, but now 12 years later we can use firmware_node/sun sysfs file. Looking at a small selection of server HW, for HPE (Gen10 DL325), the _SUN is attached to the NIC device, whereas for Dell (R640/R6515/R6615) and Cisco (UCSC-C220-M5SX), the _SUN is on the first parent pcieport. We still fallback to pci_get_hotplug_slot() to handle the s390 case and maybe some other coner cases (_SUN on grand parent device that is not a bridge ?). (cherry picked from commit 0a4ecc54cb9f2d3418b970c51bfadb69c34ae9eb) Resolves: RHEL-50103 --- man/systemd.net-naming-scheme.xml | 5 ++- src/shared/netif-naming-scheme.h | 3 +- src/udev/udev-builtin-net_id.c | 66 +++++++++++++++++++++++++++---- 3 files changed, 64 insertions(+), 10 deletions(-) diff --git a/man/systemd.net-naming-scheme.xml b/man/systemd.net-naming-scheme.xml index 83293e5636..c9a7e1e493 100644 --- a/man/systemd.net-naming-scheme.xml +++ b/man/systemd.net-naming-scheme.xml @@ -510,9 +510,10 @@ to distinguish between devices. However, name conflict can occur if these devices are not children of the same PCI bridge, e.g. there are multiple PCI bridges in the same slot. + + PCI slot number is now read from firmware_node/sun sysfs file. - By default rhel-9.0 is used. @@ -666,7 +667,7 @@ ID_NET_NAME_ONBOARD_LABEL=Ethernet Port 1 - PCI Ethernet card in hotplug slot with firmware index number + PCI Ethernet card in slot with firmware index number # /sys/devices/pci0000:00/0000:00:1c.3/0000:05:00.0/net/ens1 ID_NET_NAME_MAC=enx000000000466 diff --git a/src/shared/netif-naming-scheme.h b/src/shared/netif-naming-scheme.h index 5bc071f8db..b1ac2e4320 100644 --- a/src/shared/netif-naming-scheme.h +++ b/src/shared/netif-naming-scheme.h @@ -42,6 +42,7 @@ typedef enum NamingSchemeFlags { * This is disabled since rhel-9.5, as it seems not to work at least for some setups. See upstream issue #28929. */ NAMING_DEVICETREE_ALIASES = 1 << 15, /* Generate names from devicetree aliases */ NAMING_SR_IOV_R = 1 << 17, /* Use "r" suffix for SR-IOV VF representors */ + NAMING_FIRMWARE_NODE_SUN = 1 << 18, /* Use firmware_node/sun to get PCI slot number */ /* And now the masks that combine the features above */ NAMING_V238 = 0, @@ -73,7 +74,7 @@ typedef enum NamingSchemeFlags { NAMING_RHEL_9_2 = NAMING_RHEL_9_0, NAMING_RHEL_9_3 = NAMING_RHEL_9_0 | NAMING_SR_IOV_R, NAMING_RHEL_9_4 = NAMING_RHEL_9_3, - NAMING_RHEL_9_5 = NAMING_RHEL_9_4 & ~NAMING_BRIDGE_MULTIFUNCTION_SLOT, + NAMING_RHEL_9_5 = (NAMING_RHEL_9_4 & ~NAMING_BRIDGE_MULTIFUNCTION_SLOT) | NAMING_FIRMWARE_NODE_SUN, EXTRA_NET_NAMING_SCHEMES diff --git a/src/udev/udev-builtin-net_id.c b/src/udev/udev-builtin-net_id.c index 16c9971876..291fb4ba36 100644 --- a/src/udev/udev-builtin-net_id.c +++ b/src/udev/udev-builtin-net_id.c @@ -442,6 +442,51 @@ static int pci_get_hotplug_slot(sd_device *dev, uint32_t *ret) { return -ENOENT; } +static int get_device_firmware_node_sun(sd_device *dev, uint32_t *ret) { + const char *attr; + int r; + + assert(dev); + assert(ret); + + r = device_get_sysattr_value_filtered(dev, "firmware_node/sun", &attr); + if (r < 0) + return log_device_debug_errno(dev, r, "Failed to read firmware_node/sun, ignoring: %m"); + + r = safe_atou32(attr, ret); + if (r < 0) + return log_device_warning_errno(dev, r, "Failed to parse firmware_node/sun '%s', ignoring: %m", attr); + + return 0; +} + +static int pci_get_slot_from_firmware_node_sun(sd_device *dev, uint32_t *ret) { + int r; + sd_device *slot_dev; + + assert(dev); + assert(ret); + + /* Try getting the ACPI _SUN for the device */ + if (get_device_firmware_node_sun(dev, ret) >= 0) + return 0; + + r = sd_device_get_parent_with_subsystem_devtype(dev, "pci", NULL, &slot_dev); + if (r < 0) + return log_device_debug_errno(dev, r, "Failed to find pci parent, ignoring: %m"); + + if (is_pci_bridge(slot_dev) && is_pci_multifunction(dev) <= 0) + return log_device_debug_errno(dev, SYNTHETIC_ERRNO(ESTALE), + "Not using slot information because the parent pcieport " + "is a bridge and the PCI device is not multifunction."); + + /* Try getting the ACPI _SUN from the parent pcieport */ + if (get_device_firmware_node_sun(slot_dev, ret) >= 0) + return 0; + + return -ENOENT; +} + static int dev_pci_slot(sd_device *dev, const LinkInfo *info, NetNames *names) { const char *sysname, *attr; unsigned domain, bus, slot, func; @@ -517,13 +562,20 @@ static int dev_pci_slot(sd_device *dev, const LinkInfo *info, NetNames *names) { domain, bus, slot, func, strempty(info->phys_port_name), dev_port, special_glyph(SPECIAL_GLYPH_ARROW_RIGHT), empty_to_na(names->pci_path)); - r = pci_get_hotplug_slot(names->pcidev, &hotplug_slot); - if (r < 0) - return r; - if (r > 0) - /* If the hotplug slot is found through the function ID, then drop the domain from the name. - * See comments in parse_hotplug_slot_from_function_id(). */ - domain = 0; + if (naming_scheme_has(NAMING_FIRMWARE_NODE_SUN)) + r = pci_get_slot_from_firmware_node_sun(names->pcidev, &hotplug_slot); + else + r = -1; + /* If we don't find a slot using firmware_node/sun, fallback to hotplug_slot */ + if (r < 0) { + r = pci_get_hotplug_slot(names->pcidev, &hotplug_slot); + if (r < 0) + return r; + if (r > 0) + /* If the hotplug slot is found through the function ID, then drop the domain from the name. + * See comments in parse_hotplug_slot_from_function_id(). */ + domain = 0; + } s = names->pci_slot; l = sizeof(names->pci_slot);