From d79acc309327f8c0863bd3da8b93d926a1c93ba1 Mon Sep 17 00:00:00 2001 From: David Herrmann Date: Wed, 6 May 2015 18:18:43 +0200 Subject: bus: don't switch to kdbus if not requested Whenever systemd is re-executed, it tries to create a system bus via kdbus. If the system did not have kdbus loaded during bootup, but the module is loaded later on manually, this will cause two system buses running (kdbus and dbus-daemon in parallel). This patch makes sure we never try to create kdbus buses if it wasn't explicitly requested on the command-line. --- src/libsystemd/sd-bus/bus-util.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'src/libsystemd/sd-bus/bus-util.c') diff --git a/src/libsystemd/sd-bus/bus-util.c b/src/libsystemd/sd-bus/bus-util.c index f0695bfde0..7536a96b8d 100644 --- a/src/libsystemd/sd-bus/bus-util.c +++ b/src/libsystemd/sd-bus/bus-util.c @@ -2051,3 +2051,30 @@ int bus_path_decode_unique(const char *path, const char *prefix, char **ret_send *ret_external = external; return 1; } + +bool is_kdbus_wanted(void) { + _cleanup_free_ char *value = NULL; + int r; + + if (get_proc_cmdline_key("kdbus", NULL) <= 0) { + r = get_proc_cmdline_key("kdbus=", &value); + if (r <= 0 || parse_boolean(value) != 1) + return false; + } + + return true; +} + +bool is_kdbus_available(void) { + _cleanup_close_ int fd = -1; + struct kdbus_cmd cmd = { .size = sizeof(cmd), .flags = KDBUS_FLAG_NEGOTIATE }; + + if (!is_kdbus_wanted()) + return false; + + fd = open("/sys/fs/kdbus/control", O_RDWR | O_CLOEXEC | O_NONBLOCK | O_NOCTTY); + if (fd < 0) + return false; + + return ioctl(fd, KDBUS_CMD_BUS_MAKE, &cmd) >= 0; +} -- cgit v1.2.3-54-g00ecf