125ef27274
This is an extremely tricky race condition.
* During SIM object initialization, we try to load SIM type (first
item loaded).
* MMSimMbim SIM type loading step runs preload_subscriber_info(),
which:
** Sets self->priv->preload = TRUE; so that it is not run anymore.
** Sets the sync monitor to clear preloaded info if sync needed.
** Runs the subscriber ready status operation asynchronously.
** Just before the subscriber ready status operation returns, the
system goes to sleep.
** The resume logic kicks in, and we flag the modem with sync
needed, which clears the self->priv->preload flag.
* Then the subscriber ready status operation response arrives, and we
store the IMSI and the other things.
* When the next initialization step happens, given that
self->priv->preload is cleared, we run attempt to run
preload_subscriber_info() again, and this time it finds the info like
IMSI is already set, so asserts:
0x00007cbcd287523f (libglib-2.0.so.0 - gtestutils.c: 3253) g_assertion_message
0x00007cbcd28752a2 (libglib-2.0.so.0 - gtestutils.c: 3279) g_assertion_message_expr
0x00005cbdab0a2dc0 (ModemManager - mm-sim-mbim.c: 253) subscriber_ready_status_ready
0x00007cbcd29a173b (libgio-2.0.so.0 - gtask.c: 1230) g_task_return_now
0x00007cbcd29a0799 (libgio-2.0.so.0 - gtask.c: 1300) g_task_return
0x00007cbcd2a548e0 (libmbim-glib.so.4 - mbim-device.c: 264) transaction_task_complete_and_free
0x00007cbcd2a562fc (libmbim-glib.so.4 - mbim-device.c: 1047) data_available
0x00007cbcd28534a6 (libglib-2.0.so.0 - gmain.c: 3417) g_main_context_dispatch
0x00007cbcd28537b1 (libglib-2.0.so.0 - gmain.c: 4211) g_main_context_iterate
0x00007cbcd2853a25 (libglib-2.0.so.0 - gmain.c: 4411) g_main_loop_run
0x00005cbdab034d26 (ModemManager - main.c: 217) main
0x00007cbcd25e16c5 (libc.so.6 + 0x000286c5) __libc_init_first
0x00007cbcd25e1781 (libc.so.6 + 0x00028781) __libc_start_main
0x00005cbdab034a40 (ModemManager + 0x00061a40) _start
In order to solve this, upon a sync request the ongoing preload
operation will be cancelled.
ModemManager. ModemManager provides a unified high level API for communicating with mobile broadband modems, regardless of the protocol used to communicate with the actual device (Generic AT, vendor-specific AT, QCDM, QMI, MBIM...). Using. ModemManager is a system daemon and is not meant to be used directly from the command line. However, since it provides a DBus API, it is possible to use 'dbus-send' commands or the new 'mmcli' command line interface to control it from the terminal. The devices are queried from udev and automatically updated based on hardware events, although a manual re-scan can also be requested to look for RS232 modems. Implementation. ModemManager is a DBus system bus activated service (meaning it's started automatically when a request arrives). It is written in C, using glib and gio. Several GInterfaces specify different features that the modems support, including the generic MMIfaceModem3gpp and MMIfaceModemCdma which provide basic operations for 3GPP (GSM, UMTS, LTE) or CDMA (CDMA1x, EV-DO) modems. If a given feature is not available in the modem, the specific interface will not be exported in DBus. Plugins. Plugins are loaded on startup, and must implement the MMPlugin interface. It consists of a couple of methods which tell the daemon whether the plugin supports a port and to create custom MMBroadbandModem implementations. It most likely makes sense to derive custom modem implementations from one of the generic classes and just add (or override) operations which are not standard. There are multiple fully working plugins in the plugins/ directory that can be used as an example for writing new plugins. Writing new plugins is highly encouraged! The plugin API is open for changes, so if you're writing a plugin and need to add or change some public method, feel free to suggest it! License. The ModemManager and mmcli binaries are both GPLv2+. The libmm-glib library is LGPLv2+. Code of Conduct. Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms, which you can find in the following link: https://www.freedesktop.org/wiki/CodeOfConduct CoC issues may be raised to the project maintainers at the following address: modemmanager-devel-owner@lists.freedesktop.org