systemd/0080-backport-udev-net_id-don-t-generate-slot-based-names-if-multi.patch
2021-05-30 22:04:06 -04:00

131 lines
5.9 KiB
Diff

From 2c8ec0095e6fd2e72879d4915ff8a9e5c0664d0b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Michal=20Sekleta=CC=81r?= <msekleta@redhat.com>
Date: Mon, 19 Oct 2020 11:10:31 +0200
Subject: [PATCH] udev/net_id: don't generate slot based names if multiple
devices might claim the same slot
---
man/systemd.net-naming-scheme.xml | 14 ++++++++++++++
src/udev/net/naming-scheme.c | 1 +
src/udev/net/naming-scheme.h | 2 ++
src/udev/udev-builtin-net_id.c | 29 ++++++++++++++++++++++++++++-
4 files changed, 45 insertions(+), 1 deletion(-)
diff --git a/man/systemd.net-naming-scheme.xml b/man/systemd.net-naming-scheme.xml
index 91ad57d..40d7e58 100644
--- a/man/systemd.net-naming-scheme.xml
+++ b/man/systemd.net-naming-scheme.xml
@@ -182,6 +182,9 @@
<para>SR-IOV virtual devices are named based on the name of the parent interface, with a suffix of
<constant>v</constant> and the virtual device number, with any leading zeros removed. The bus
number is ignored. This device type is found in IBM PowerVMs.</para>
+
+ <para>In some configurations a parent PCI bridge of a given network controller may be associated
+ with a slot. In such case we don't generate this device property to avoid possible naming conflicts.</para>
</varlistentry>
<varlistentry>
@@ -329,6 +332,17 @@
<para>Previously two-letter interface type prefix was prepended to
<varname>ID_NET_LABEL_ONBOARD=</varname>. This is not done anymore.</para></listitem>
</varlistentry>
+
+ <varlistentry>
+ <term><constant>v246</constant></term>
+
+ <listitem><para>If the PCI slot is assocated with PCI bridge and that has multiple child network
+ controllers then all of them might derive the same value of <varname>ID_NET_NAME_SLOT</varname>
+ property. That could cause naming conflict if the property is selected as a device name. Now, we detect the
+ situation, slot - bridge relation, and we don't produce the <varname>ID_NET_NAME_SLOT</varname> property to
+ avoid possible naming conflict.</para></listitem>
+ </varlistentry>
+
</variablelist>
<para>Note that <constant>latest</constant> may be used to denote the latest scheme known (to this
diff --git a/src/udev/net/naming-scheme.c b/src/udev/net/naming-scheme.c
index 0d7f413..ebab2ff 100644
--- a/src/udev/net/naming-scheme.c
+++ b/src/udev/net/naming-scheme.c
@@ -10,6 +10,7 @@ static const NamingScheme naming_schemes[] = {
{ "v240", NAMING_V240 },
{ "v241", NAMING_V241 },
{ "v243", NAMING_V243 },
+ { "v246", NAMING_V246 },
/* … add more schemes here, as the logic to name devices is updated … */
};
diff --git a/src/udev/net/naming-scheme.h b/src/udev/net/naming-scheme.h
index 38dfa75..d744f3e 100644
--- a/src/udev/net/naming-scheme.h
+++ b/src/udev/net/naming-scheme.h
@@ -30,6 +30,7 @@ typedef enum NamingSchemeFlags {
NAMING_STABLE_VIRTUAL_MACS = 1 << 5, /* Use device name to generate MAC, see 6d3646406560 */
NAMING_NETDEVSIM = 1 << 6, /* Generate names for netdevsim devices, see eaa9d507d855 */
NAMING_LABEL_NOPREFIX = 1 << 7, /* Don't prepend ID_NET_LABEL_ONBOARD with interface type prefix */
+ NAMING_BRIDGE_NO_SLOT = 1 << 9, /* Don't use PCI hotplug slot information if the corresponding device is a PCI bridge */
/* And now the masks that combine the features above */
NAMING_V238 = 0,
@@ -37,6 +38,7 @@ typedef enum NamingSchemeFlags {
NAMING_V240 = NAMING_V239 | NAMING_INFINIBAND | NAMING_ZERO_ACPI_INDEX | NAMING_ALLOW_RERENAMES,
NAMING_V241 = NAMING_V240 | NAMING_STABLE_VIRTUAL_MACS,
NAMING_V243 = NAMING_V241 | NAMING_NETDEVSIM | NAMING_LABEL_NOPREFIX,
+ NAMING_V246 = NAMING_V243 | NAMING_BRIDGE_NO_SLOT,
_NAMING_SCHEME_FLAGS_INVALID = -1,
} NamingSchemeFlags;
diff --git a/src/udev/udev-builtin-net_id.c b/src/udev/udev-builtin-net_id.c
index 99d44a2..af0d2a7 100644
--- a/src/udev/udev-builtin-net_id.c
+++ b/src/udev/udev-builtin-net_id.c
@@ -244,6 +244,25 @@ static bool is_pci_ari_enabled(sd_device *dev) {
return streq(a, "1");
}
+static bool is_pci_bridge(sd_device *dev) {
+ const char *v, *p;
+
+ if (sd_device_get_sysattr_value(dev, "modalias", &v) < 0)
+ return false;
+
+ if (!startswith(v, "pci:"))
+ return false;
+
+ p = strrchr(v, 's');
+ if (!p)
+ return false;
+ if (p[1] != 'c')
+ return false;
+
+ /* PCI device subclass 04 corresponds to PCI bridge */
+ return strneq(p + 2, "04", 2);
+}
+
static int dev_pci_slot(sd_device *dev, struct netnames *names) {
unsigned long dev_port = 0;
unsigned domain, bus, slot, func;
@@ -343,10 +362,18 @@ static int dev_pci_slot(sd_device *dev, struct netnames *names) {
read_one_line_file(str, &address) >= 0 &&
startswith(sysname, address)) {
hotplug_slot = i;
+
+ /* We found the match between PCI device and slot. However, we won't use the
+ * slot index if the device is a PCI bridge, because it can have other child
+ * devices that will try to claim the same index and that would create name
+ * collision. */
+ if (naming_scheme_has(NAMING_BRIDGE_NO_SLOT) && is_pci_bridge(hotplug_slot_dev))
+ hotplug_slot = 0;
+
break;
}
}
- if (hotplug_slot > 0)
+ if (hotplug_slot >= 0)
break;
if (sd_device_get_parent_with_subsystem_devtype(hotplug_slot_dev, "pci", NULL, &hotplug_slot_dev) < 0)
break;
--
2.23.0