Jarod Wilson 08aeb7c9a4 [media] rc: add locking to fix register/show race ... When device_add is called in rc_register_device, the rc sysfs nodes show up, and there's a window in which ir-keytable can be launched via udev and trigger a show_protocols call, which runs without various rc_dev fields filled in yet. Add some locking around registration and store/show_protocols to prevent that from happening. The problem manifests thusly: [64692.957872] BUG: unable to handle kernel NULL pointer dereference at 0000000000000090 [64692.957878] IP: [<ffffffffa036a4c1>] show_protocols+0x47/0xf1 [rc_core] [64692.957890] PGD 19cfc7067 PUD 19cfc6067 PMD 0 [64692.957894] Oops: 0000 [#1] SMP [64692.957897] last sysfs file: /sys/devices/pci0000:00/0000:00:03.1/usb3/3-1/3-1:1.0/rc/rc2/protocols [64692.957902] CPU 3 [64692.957903] Modules linked in: redrat3(+) ir_lirc_codec lirc_dev ir_sony_decoder ir_jvc_decoder ir_rc6_decoder ir_rc5_decoder rc_hauppauge ir_nec _decoder rc_core ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables snd_emu10k1_synth snd_emux_synth snd_seq_virmidi snd_seq_mi di_event snd_seq_midi_emul snd_emu10k1 snd_rawmidi snd_ac97_codec ac97_bus snd_seq snd_pcm snd_seq_device snd_timer snd_page_alloc snd_util_mem pcsp kr tg3 snd_hwdep emu10k1_gp snd amd64_edac_mod gameport edac_core soundcore edac_mce_amd k8temp shpchp i2c_piix4 lm63 e100 mii uinput ipv6 raid0 rai d1 ata_generic firewire_ohci pata_acpi firewire_core crc_itu_t sata_svw pata_serverworks floppy radeon ttm drm_kms_helper drm i2c_algo_bit i2c_core [last unloaded: redrat3] [64692.957949] [64692.957952] Pid: 12265, comm: ir-keytable Tainted: G M W 2.6.39-rc6+ #2 empty empty/TYAN Thunder K8HM S3892 [64692.957957] RIP: 0010:[<ffffffffa036a4c1>] [<ffffffffa036a4c1>] show_protocols+0x47/0xf1 [rc_core] [64692.957962] RSP: 0018:ffff880194509e38 EFLAGS: 00010202 [64692.957964] RAX: 0000000000000000 RBX: ffffffffa036d1e0 RCX: ffffffffa036a47a [64692.957966] RDX: ffff88019a84d000 RSI: ffffffffa036d1e0 RDI: ffff88019cf2f3f0 [64692.957969] RBP: ffff880194509e68 R08: 0000000000000002 R09: 0000000000000000 [64692.957971] R10: 0000000000000002 R11: 0000000000001617 R12: ffff88019a84d000 [64692.957973] R13: 0000000000001000 R14: ffff8801944d2e38 R15: ffff88019ce5f190 [64692.957976] FS: 00007f0a30c9a720(0000) GS:ffff88019fc00000(0000) knlGS:0000000000000000 [64692.957979] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [64692.957981] CR2: 0000000000000090 CR3: 000000019a8e0000 CR4: 00000000000006e0 [64692.957983] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [64692.957986] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [64692.957989] Process ir-keytable (pid: 12265, threadinfo ffff880194508000, task ffff88019a9fc720) [64692.957991] Stack: [64692.957992] 0000000000000002 ffffffffa036d1e0 ffff880194509f58 0000000000001000 [64692.957997] ffff8801944d2e38 ffff88019ce5f190 ffff880194509e98 ffffffff8131484b [64692.958001] ffffffff8118e923 ffffffff810e9b2f ffff880194509e98 ffff8801944d2e18 [64692.958005] Call Trace: [64692.958014] [<ffffffff8131484b>] dev_attr_show+0x27/0x4e [64692.958014] [<ffffffff8118e923>] ? sysfs_read_file+0x94/0x172 [64692.958014] [<ffffffff810e9b2f>] ? __get_free_pages+0x16/0x52 [64692.958014] [<ffffffff8118e94c>] sysfs_read_file+0xbd/0x172 [64692.958014] [<ffffffff8113205e>] vfs_read+0xac/0xf3 [64692.958014] [<ffffffff8113347b>] ? fget_light+0x3a/0xa1 [64692.958014] [<ffffffff811320f2>] sys_read+0x4d/0x74 [64692.958014] [<ffffffff814c19c2>] system_call_fastpath+0x16/0x1b Its a bit difficult to reproduce, but I'm fairly confident this has fixed the problem. Signed-off-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>		2011-05-20 16:21:22 -03:00
..
davinci	Fix common misspellings	2011-03-31 11:26:23 -03:00
adv7343.h	V4L/DVB (11743): Analog Devices ADV7343 video encoder driver	2009-06-16 18:20:59 -03:00
ak881x.h	V4L/DVB: V4L: v4l2-subdev driver for AK8813 and AK8814 TV-encoders from AKM	2010-05-19 12:58:02 -03:00
bt819.h	[media] bt819: the ioctls in the header are internal to the kernel	2010-12-29 08:17:19 -02:00
cs53l32a.h
cs5345.h	V4L/DVB (6869): cs5345: new i2c driver	2008-01-25 19:04:08 -02:00
cx2341x.h	[media] v4l2-ctrls: use const char * const * for the menu arrays	2010-12-30 08:02:14 -02:00
cx25840.h	V4L/DVB: cx25840/ivtv: replace ugly priv control with s_config	2010-08-08 23:43:05 -03:00
i2c-addr.h	V4L/DVB (9940): bt832: remove this driver	2008-12-30 09:39:25 -02:00
ir-kbd-i2c.h	[media] rc: Rename remote controller type to rc_type instead of ir_type	2010-12-29 08:16:50 -02:00
lirc.h	Fix common misspellings	2011-03-31 11:26:23 -03:00
lirc_dev.h	[media] lirc_dev: add some __user annotations	2010-12-29 08:16:55 -02:00
m52790.h	V4L/DVB (6486): m52790: add new Mitsubishi A/V switch i2c driver	2008-01-25 19:01:46 -02:00
media-device.h	[media] media: Links setup	2011-03-22 04:53:16 -03:00
media-devnode.h	[media] media: Media device node support	2011-03-22 04:52:22 -03:00
media-entity.h	[media] media: Pipelines and media streams	2011-03-22 04:53:17 -03:00
msp3400.h	V4L/DVB (11380): v4l2-subdev: change s_routing prototype	2009-04-06 21:44:27 -03:00
mt9t112.h	V4L/DVB (13670): soc-camera: Add mt9t112 camera driver	2009-12-16 09:27:41 -02:00
mt9v011.h	[media] v4l2-subdev: remove core.s_config and v4l2_i2c_new_subdev_cfg()	2011-01-19 11:45:30 -02:00
mt9v032.h	[media] v4l: Add mt9v032 sensor driver	2011-05-20 09:29:49 -03:00
noon010pc30.h	[media] Add v4l2 subdev driver for NOON010PC30L image sensor	2011-03-21 20:31:40 -03:00
omap1_camera.h	[media] SoC Camera: add driver for OMAP1 camera interface	2010-10-21 07:55:37 -02:00
ov772x.h	soc-camera: ov772x: Modify buswidth control	2010-02-26 15:11:00 -03:00
pwc-ioctl.h	v4l-dvb: remove legacy checks to allow support for kernels < 2.6.10	2008-07-20 07:17:52 -03:00
radio-si4713.h	V4L/DVB (12551): FM TX: si4713: Add files to add radio interface for si4713	2009-09-12 12:19:19 -03:00
rc-core.h	[media] rc: add locking to fix register/show race	2011-05-20 16:21:22 -03:00
rc-map.h	[media] rc: add tivo/nero liquidtv keymap	2011-05-20 09:27:29 -03:00
rj54n1cb0c.h	V4L/DVB (13661): rj54n1cb0c: Add cropping, auto white balance, restrict sizes, add platform data	2009-12-16 09:27:30 -02:00
s5p_fimc.h	[media] s5p-fimc: Add a platform data entry for MIPI-CSI data alignment	2011-03-22 04:54:18 -03:00
saa6588.h	[media] saa6588: rename rds.h to saa6588.h	2010-12-29 08:17:18 -02:00
saa6752hs.h
saa7115.h	V4L/DVB (8940): saa7115: fix saa7111(a) support	2008-10-12 09:37:00 -02:00
saa7127.h
saa7146.h	[media] saa7146: Convert from .ioctl to .unlocked_ioctl	2011-01-19 11:28:10 -02:00
saa7146_vv.h	V4L/DVB: saa7146: fix regression of the av7110/budget-av driver	2010-05-06 19:20:50 -03:00
sh_mobile_ceu.h	V4L/DVB: V4L2: sh_mobile_camera_ceu: add support for CSI2	2010-08-02 16:43:40 -03:00
sh_mobile_csi2.h	V4L/DVB: V4L2: soc-camera: add a MIPI CSI-2 driver for SH-Mobile platforms	2010-08-02 16:43:39 -03:00
sh_vou.h	[media] sh_vou: Don't use module names to load I2C modules	2010-10-22 21:53:33 -02:00
si4713.h	[media] radio-si4713: Add regulator framework support	2010-12-29 08:16:35 -02:00
soc_camera.h	[media] V4L: soc-camera: add MIPI bus flags	2011-05-20 12:00:41 -03:00
soc_camera_platform.h	[media] V4L: soc_camera_platform: add helper functions to manage device instances	2011-05-20 07:26:14 -03:00
soc_mediabus.h	[media] V4L: soc-camera: add a new packing for YUV 4:2:0 type formats	2011-05-20 12:05:08 -03:00
sr030pc30.h	[media] Add driver for Siliconfile SR030PC30 VGA camera	2010-10-21 07:55:49 -02:00
timb_radio.h	[media] media: Add timberdale video-in driver	2010-12-29 08:16:46 -02:00
timb_video.h	[media] media: Add timberdale video-in driver	2010-12-29 08:16:46 -02:00
tuner-types.h	V4L/DVB (7352): tuner-simple: enable digital tuning support for Philips FMD1216ME	2008-04-24 14:07:50 -03:00
tuner.h	[media] tuner: Remove remaining usages of T_DIGITAL_TV	2011-03-21 20:32:04 -03:00
tvaudio.h	V4L/DVB (11376): tvaudio.h: add static inline to retrieve the list of possible i2c addrs.	2009-04-06 21:44:25 -03:00
tveeprom.h	V4L/DVB (8479): tveeprom/ivtv: fix usage of has_ir field	2008-07-26 12:54:42 -03:00
tvp514x.h	V4L/DVB (12246): tvp514x: Migration to sub-device framework	2009-09-19 00:18:09 -03:00
tvp5150.h
tvp7002.h	V4L/DVB: Definitions for TVP7002 in DM365	2010-02-26 15:11:01 -03:00
tw9910.h	tw9910: use TABs for indentation	2010-02-26 15:10:59 -03:00
upd64031a.h
upd64083.h
v4l2-chip-ident.h	[media] V4L: Initial submit of OV9740 driver	2011-03-21 20:32:16 -03:00
v4l2-common.h	[media] v4l2_prio: move from v4l2-common to v4l2-dev	2011-03-22 16:37:54 -03:00
v4l2-ctrls.h	[media] v4l: Include linux/videodev2.h in media/v4l2-ctrls.h	2011-01-19 11:52:09 -02:00
v4l2-dev.h	[media] Revert "V4L/DVB: v4l2-dev: remove get_unmapped_area"	2011-05-20 12:14:40 -03:00
v4l2-device.h	[media] v4l2-device: fix a macro definition	2011-04-13 09:53:29 -03:00
v4l2-event.h	V4L/DVB: V4L: Events: Add backend	2010-05-19 12:58:06 -03:00
v4l2-fh.h	[media] v4l2-fh: add v4l2_fh_is_singular	2011-03-22 16:37:58 -03:00
v4l2-int-device.h	V4L/DVB (10141): v4l2: debugging API changed to match against driver name instead of ID.	2009-01-02 17:11:52 -02:00
v4l2-ioctl.h	[media] v4l2-ioctl: add priority handling support	2011-03-22 16:37:59 -03:00
v4l2-mediabus.h	[media] v4l: Move the media/v4l2-mediabus.h header to include/linux	2011-03-22 04:53:21 -03:00
v4l2-mem2mem.h	[media] Update Pawel Osciak's e-mail address	2011-03-22 04:55:05 -03:00
v4l2-subdev.h	[media] v4l: Add subdev sensor g_skip_frames operation	2011-03-22 04:53:34 -03:00
videobuf-core.h	[media] V4L: remove V4L1 compatibility mode	2010-12-29 08:17:07 -02:00
videobuf-dma-contig.h	V4L/DVB: videobuf: add ext_lock argument to the queue init functions	2010-10-21 01:06:14 -02:00
videobuf-dma-sg.h	V4L/DVB: videobuf: add ext_lock argument to the queue init functions	2010-10-21 01:06:14 -02:00
videobuf-dvb.h	V4L/DVB (13103): create a standard method for dvb adapter drivers to override frontend ioctls	2009-12-05 18:40:21 -02:00
videobuf-vmalloc.h	V4L/DVB: videobuf: add ext_lock argument to the queue init functions	2010-10-21 01:06:14 -02:00
videobuf2-core.h	[media] Update Pawel Osciak's e-mail address	2011-03-22 04:55:05 -03:00
videobuf2-dma-contig.h	[media] videobuf2-dma-contig: make cookie() return a pointer to dma_addr_t	2011-03-22 19:41:58 -03:00
videobuf2-dma-sg.h	[media] v4l: videobuf2: add DMA scatter/gather allocator	2011-03-21 20:31:34 -03:00
videobuf2-memops.h	[media] Update Pawel Osciak's e-mail address	2011-03-22 04:55:05 -03:00
videobuf2-vmalloc.h	[media] Update Pawel Osciak's e-mail address	2011-03-22 04:55:05 -03:00
wm8775.h	[media] Add proper audio support for Nova-S Plus with wm8775 ADC	2011-03-21 20:32:19 -03:00