[Qemu-devel] [PATCH] tap: forbid creating multiqueue tap when hub is used

[Jason Wang]

Obviously, hub does not support multiqueue tap. So this patch forbids creating
multiple queue tap when hub is used to prevent the crash when command line such
as "-net tap,queues=2" is used.

Signed-off-by: Jason Wang <address@hidden>
---
This patch is needed for 1.4 stable also.
---
 net/tap.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/net/tap.c b/net/tap.c
index 48c254e..1e14f59 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -693,6 +693,12 @@ int net_init_tap(const NetClientOptions *opts, const char 
*name,
     queues = tap->has_queues ? tap->queues : 1;
     vhostfdname = tap->has_vhostfd ? tap->vhostfd : NULL;
 
+    if (peer && (tap->has_queues || tap->has_fds || tap->has_vhostfds)) {
+        error_report("This configuration is not compatiable with multiqueue"
+                     " tap");
+        return -1;
+    }
+
     if (tap->has_fd) {
         if (tap->has_ifname || tap->has_script || tap->has_downscript ||
             tap->has_vnet_hdr || tap->has_helper || tap->has_queues ||
-- 
1.7.1