File libvirt-util-avoid-getting-stuck-on-macvtapN-name-created-outside-libvirt.patch of Package libvirt

From 91d3e9bbe1de57ace09bf88c9b28283bf4a715f6 Mon Sep 17 00:00:00 2001
Message-Id: <91d3e9bbe1de57ace09bf88c9b28283bf4a715f6@dist-git>
From: Laine Stump <laine@laine.org>
Date: Mon, 28 Mar 2016 15:49:23 -0400
Subject: [PATCH] util: avoid getting stuck on macvtapN name created outside
 libvirt

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1321637

(This was a regression caused by a patch backported for Bug 1276478)

After the patches that added tracking of in-use macvtap names (commit
370608, first appearing in libvirt-1.3.2), if the function to allocate
a new macvtap device came to a device name created outside libvirt, it
would retry the same device name MACVLAN_MAX_ID (8191) times before
finally giving up in failure.

The problem was that virBitmapNextClearBit was always being called
with "0" rather than the value most recently checked (which would
increment each time through the loop), so it would always return the
same id (since we dutifully release that id after failing to create a
new device using it).

Also Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1321546 (RHEL7)

Signed-off-by: Laine Stump <laine@laine.org>
(cherry picked from commit 5b5f12cffa86a1b4527bde620c2a86c5e96ad7c5)
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
---
 src/util/virnetdevmacvlan.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/util/virnetdevmacvlan.c b/src/util/virnetdevmacvlan.c
index 4e5d2bb..e169120 100644
--- a/src/util/virnetdevmacvlan.c
+++ b/src/util/virnetdevmacvlan.c
@@ -138,7 +138,7 @@ virNetDevMacVLanReserveID(int id, unsigned int flags,
     }
 
     if ((id < 0 || nextFree) &&
-        (id = virBitmapNextClearBit(bitmap, 0)) < 0) {
+        (id = virBitmapNextClearBit(bitmap, id)) < 0) {
         virReportError(VIR_ERR_INTERNAL_ERROR,
                        _("no unused %s names available"),
                        (flags & VIR_NETDEV_MACVLAN_CREATE_WITH_TAP) ?
-- 
2.8.0