atmodem: gprs context deactivate crashes ofonod

Hello again,

I have been testing ofono with my Huawei E1552 usb stick, which is using atmodem and PPP. I noticed that whenever I call test/deactivate-context ofono either crashes or busyloops here in at_gprs_deactivate_primary():

	if (g_at_chat_send(gcd->chat, buf, none_prefix,
				at_cgact_down_cb, cbd, g_free) > 0)
		return;

Further investigation revealed that gcd->chat is already unreferenced in setup_ppp():

	g_at_chat_unref(gcd->chat);

So there's a conflict here. How to handle this properly? Calling g_at_ppp_shutdown() is most likely not enough, because nobody is not creating gcd->chat again which is needed during subsequent activate call.

Comments?

Hi Kalle,

Quoted 18 lines

I have been testing ofono with my Huawei E1552 usb stick, which is using atmodem and PPP. I noticed that whenever I call test/deactivate-context ofono either crashes or busyloops here in at_gprs_deactivate_primary():

	if (g_at_chat_send(gcd->chat, buf, none_prefix,
				at_cgact_down_cb, cbd, g_free) > 0)
		return;

Further investigation revealed that gcd->chat is already unreferenced in setup_ppp():

	g_at_chat_unref(gcd->chat);

So there's a conflict here. How to handle this properly? Calling g_at_ppp_shutdown() is most likely not enough, because nobody is not creating gcd->chat again which is needed during subsequent activate call.

Quoted 2 lines

Comments?

Deactivation of the context was never made to work properly. For a hint, please have a look at gatchat/gsmdial.c. When PPP is established we should be using g_at_chat_suspend. During a context deactivation we should use g_at_ppp_shutdown and then reactivate the gatchat using g_at_chat_resume

(assuming the Huawei does not HUP the tty when disconnecting the ppp link.)