libvirt/71d56a39-nodedev-fix-parse-PCI-address.patch

commit 71d56a397925a1bd55d3aee30afdbdcd1a14f9a8
Author: Jim Fehlig <jfehlig@suse.com>
Date:   Fri Jan 5 17:10:47 2018 -0700

    nodedev: Fix failing to parse PCI address for non-PCI network devices
    
    Commit 8708ca01c added virNetDevSwitchdevFeature() to check if a network
    device has Switchdev capabilities. virNetDevSwitchdevFeature() attempts
    to retrieve the PCI device associated with the network device, ignoring
    non-PCI devices. It does so via the following call chain
    
      virNetDevSwitchdevFeature()->virNetDevGetPCIDevice()->
      virPCIGetDeviceAddressFromSysfsLink()
    
    For non-PCI network devices (qeth, Xen vif, etc),
    virPCIGetDeviceAddressFromSysfsLink() will report an error when
    virPCIDeviceAddressParse() fails. virPCIDeviceAddressParse() also
    logs an error. After commit 8708ca01c there are now two errors reported
    for each non-PCI network device even though the errors are harmless.
    
    To avoid the errors, introduce virNetDevIsPCIDevice() and use it in
    virNetDevGetPCIDevice() before attempting to retrieve the associated
    PCI device. virNetDevIsPCIDevice() uses the 'subsystem' property of the
    device to determine if it is PCI. See the sysfs rules in kernel
    documentation for more details
    
    https://www.kernel.org/doc/html/latest/admin-guide/sysfs-rules.html

Index: libvirt-4.0.0/src/util/virnetdev.c
===================================================================
--- libvirt-4.0.0.orig/src/util/virnetdev.c
+++ libvirt-4.0.0/src/util/virnetdev.c
@@ -22,6 +22,7 @@
 
 #include <config.h>
 
+#include "dirname.h"
 #include "virnetdev.h"
 #include "virnetlink.h"
 #include "virmacaddr.h"
@@ -1147,6 +1148,45 @@ virNetDevSysfsDeviceFile(char **pf_sysfs
     return 0;
 }
 
+/**
+ * Determine if the device path specified in devpath is a PCI Device
+ * by resolving the 'subsystem'-link in devpath and looking for
+ * 'pci' in the last component. For more information see the rules
+ * for accessing sysfs in the kernel docs
+ *
+ * https://www.kernel.org/doc/html/latest/admin-guide/sysfs-rules.html
+ *
+ * Returns true if devpath's susbsystem is pci, false otherwise.
+ */
+static bool
+virNetDevIsPCIDevice(const char *devpath)
+{
+    char *subsys_link = NULL;
+    char *abs_path = NULL;
+    char *subsys = NULL;
+    bool ret = false;
+
+    if (virAsprintf(&subsys_link, "%s/subsystem", devpath) < 0)
+        return false;
+
+    if (!virFileExists(subsys_link))
+        goto cleanup;
+
+    if (virFileResolveLink(subsys_link, &abs_path) < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("Unable to resolve device subsystem symlink %s"),
+                       subsys_link);
+        goto cleanup;
+    }
+
+    subsys = last_component(abs_path);
+    ret = STRPREFIX(subsys, "pci");
+
+ cleanup:
+    VIR_FREE(subsys_link);
+    VIR_FREE(abs_path);
+    return ret;
+}
 
 static virPCIDevicePtr
 virNetDevGetPCIDevice(const char *devName)
@@ -1158,6 +1198,9 @@ virNetDevGetPCIDevice(const char *devNam
     if (virNetDevSysfsFile(&vfSysfsDevicePath, devName, "device") < 0)
         goto cleanup;
 
+    if (!virNetDevIsPCIDevice(vfSysfsDevicePath))
+        goto cleanup;
+
     vfPCIAddr = virPCIGetDeviceAddressFromSysfsLink(vfSysfsDevicePath);
     if (!vfPCIAddr)
         goto cleanup;