scripts/runqemu: Improve lockfile handling for python with close_fd=True

On python versions with close_fds=True (python 3.2 onwards), the tap
device lockfile isn't passed to the child process.

Since this guards against use of an active interface, we really want this
here, so pass it in pass_fds. This means if the parent exits early, the child
still holds the lock, avoiding messages like:

runqemu - ERROR - Failed to run qemu: qemu-system-x86_64: could not configure /dev/net/tun (tap0): Device or resource busy

(From OE-Core rev: 17a0a067d597c445c5892ff9914e91a2187f7e09)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

diff --git a/scripts/runqemu b/scripts/runqemu
index 1eeafa9f5b8de0aad860fba1c7a3b1e1b34e42d9..295c8b1b605ec6531ba1afad5e7498d531e8a949 100755 (executable)
--- a/scripts/runqemu
+++ b/scripts/runqemu
@@ -1218,7 +1218,10 @@ class BaseConfig(object):
         cmd = "%s %s" % (self.qemu_opt, kernel_opts)
         cmds = shlex.split(cmd)
         logger.info('Running %s\n' % cmd)
-        process = subprocess.Popen(cmds, stderr=subprocess.PIPE)
+        pass_fds = []
+        if self.lock_descriptor:
+            pass_fds = [self.lock_descriptor.fileno()]
+        process = subprocess.Popen(cmds, stderr=subprocess.PIPE, pass_fds=pass_fds)
         self.qemupid = process.pid
         retcode = process.wait()
         if retcode: