From f5747e26f970288c161d947790b2838384971434 Mon Sep 17 00:00:00 2001
Message-Id: <f5747e26f970288c161d947790b2838384971434.1389183248.git.jdenemar@redhat.com>
From: Laine Stump <laine@laine.org>
Date: Tue, 24 Dec 2013 04:24:03 -0700
Subject: [PATCH] qemu: avoid duplicate security label restore on hostdev
 attach failure

This eliminates the misleading error message that was being logged
when a vfio hostdev hotplug failed:

  error: unable to set user and group to '107:107' on '/dev/vfio/22':
         No such file or directory

as documented in:

  https://bugzilla.redhat.com/show_bug.cgi?id=1035490

Commit ee414b5d (pushed as a fix for Bug 1016511 and part of Bug
1025108) replaced the single call to
virSecurityManagerSetHostdevLabel() in qemuDomainAttachHostDevice()
with individual calls to that same function in each
device-type-specific attach function (for PCI, USB, and SCSI). It also
added a corresponding call to virSecurityManagerRestoreHostdevLabel()
in the error handling of the device-type-specific functions, but
forgot to remove the common call to that from
qemuDomainAttachHostDevice() - this resulted in a duplicate call to
virSecurityManagerRestoreHostdevLabel(), with the second occurrence
being after (e.g.) a PCI device has already been re-attached to the
host driver, thus destroying some of the device nodes / links that we
then attempted to re-label (e.f. /dev/vfio/22) and generating an error
log that obscured the original error.

(cherry picked from commit c0f511ee2bfeb4b177b301ed73f3a9d86b4d4dbd)

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
---
 src/qemu/qemu_hotplug.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index fae7e14..0f2be8a 100644
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -1520,9 +1520,6 @@ int qemuDomainAttachHostDevice(virQEMUDriverPtr driver,
     return 0;
 
 error:
-    if (virSecurityManagerRestoreHostdevLabel(driver->securityManager,
-                                              vm->def, hostdev, NULL) < 0)
-        VIR_WARN("Unable to restore host device labelling on hotplug fail");
     return -1;
 }
 
-- 
1.8.5.2