linux/drivers/media/dvb/dvb-core
matthieu castet e36309f54a V4L/DVB: fix dvb frontend lockup
If my dvb device is removed while in use, I got the following oops:

[ 4920.484084] Call Trace:
[ 4920.484102]  [<c102daad>] ? default_wake_function+0x0/0x8
[ 4920.484147]  [<f8cb09e1>] ? dvb_unregister_frontend+0x95/0xcc [dvb_core]
[ 4920.484157]  [<c1044412>] ? autoremove_wake_function+0x0/0x2d
[ 4920.484168]  [<f8dd1af2>] ? dvb_usb_adapter_frontend_exit+0x12/0x21 [dvb_usb]
[ 4920.484176]  [<f8dd12f1>] ? dvb_usb_exit+0x26/0x88 [dvb_usb]
[ 4920.484184]  [<f8dd138d>] ? dvb_usb_device_exit+0x3a/0x4a [dvb_usb]
[ 4920.484217]  [<f7fe1b08>] ? usb_unbind_interface+0x3f/0xb4 [usbcore]
[ 4920.484227]  [<c11a4178>] ? __device_release_driver+0x74/0xb7
[ 4920.484233]  [<c11a4247>] ? device_release_driver+0x15/0x1e
[ 4920.484243]  [<c11a3a33>] ? bus_remove_device+0x6e/0x87
[ 4920.484249]  [<c11a26d6>] ? device_del+0xfa/0x152
[ 4920.484264]  [<f7fdf609>] ? usb_disable_device+0x59/0xb9 [usbcore]
[ 4920.484279]  [<f7fdb9ee>] ? usb_disconnect+0x70/0xdc [usbcore]
[ 4920.484294]  [<f7fdc728>] ? hub_thread+0x521/0xe1d [usbcore]
[ 4920.484301]  [<c1044412>] ? autoremove_wake_function+0x0/0x2d
[ 4920.484316]  [<f7fdc207>] ? hub_thread+0x0/0xe1d [usbcore]
[ 4920.484321]  [<c10441e0>] ? kthread+0x61/0x66
[ 4920.484327]  [<c104417f>] ? kthread+0x0/0x66
[ 4920.484336]  [<c1003d47>] ? kernel_thread_helper+0x7/0x10

If there are users (for example users == -2) :
 - dvb_unregister_frontend :
 - stop kernel thread with dvb_frontend_stop :
  - fepriv->exit = 1;
  - thread loop catch stop event and break while loop
  - fepriv->thread = NULL; and fepriv->exit = 0;
 - dvb_unregister_frontend wait on "fepriv->dvbdev->wait_queue" that fepriv->dvbdev->users==-1.
The user finish :
 - dvb_frontend_release - set users to -1
 - don't wait wait_queue because fepriv->exit != 1

=> dvb_unregister_frontend never exit the wait queue.

Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:59:15 -03:00
..
demux.h V4L/DVB (8131): dmx_write: memcpy from user-supplied pointer 2008-07-20 07:13:27 -03:00
dmxdev.c V4L/DVB: dvb-core: fix initialization of feeds list in demux filter 2010-02-08 10:47:17 -02:00
dmxdev.h include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
dvb_ca_en50221.c V4L/DVB (10391): dvb: constify VFTs 2009-03-30 12:42:34 -03:00
dvb_ca_en50221.h V4L/DVB (9054): implement proper locking in the dvb ca en50221 driver 2009-01-29 08:35:37 -02:00
dvb_demux.c V4L/DVB: Allow to enable TS continuity and TEI check on loaded module 2010-05-18 00:46:32 -03:00
dvb_demux.h V4L/DVB (13271): TS speed check. Logging transport stream speed in Kbits per second 2009-12-05 18:41:11 -02:00
dvb_filter.c
dvb_filter.h
dvb_frontend.c V4L/DVB: fix dvb frontend lockup 2010-05-19 12:59:15 -03:00
dvb_frontend.h include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
dvb_math.c
dvb_math.h
dvb_net.c Merge branch 'master' of /home/davem/src/GIT/linux-2.6/ 2010-02-28 19:23:06 -08:00
dvb_net.h V4L/DVB (5512): Fix 3/3 for bug 7819: fixed hotplugging for dvbnet 2007-04-27 15:45:32 -03:00
dvb_ringbuffer.c V4L/DVB: DVB: Export dvb_ringbuffer_flush() again 2010-02-26 15:10:54 -03:00
dvb_ringbuffer.h V4L/DVB (8130): split dvb_ringbuffer dual-use functions 2008-07-20 07:13:23 -03:00
dvbdev.c Driver-Core: extend devnode callbacks to provide permissions 2009-09-19 12:50:38 -07:00
dvbdev.h V4L/DVB (13103): create a standard method for dvb adapter drivers to override frontend ioctls 2009-12-05 18:40:21 -02:00
Makefile