V4L/DVB (10229): cx88-dvb: Fix order of frontend allocations

On Fri, 2009-01-09 at 15:40 +0300, Goga777 wrote:
> hI
>
> With today v4l-dvb I couldn't run my hvr4000 card on 2.6.27 kernel

> [   14.555162] cx88/2: cx2388x dvb driver version 0.0.6 loaded
> [   14.555231] cx88/2: registering cx8802 driver, type: dvb access: shared
> [   14.555303] cx88[0]/2: subsystem: 0070:6900, board: Hauppauge WinTV-HVR4000 DVB-S/S2/T/Hybrid [card=68]
> [   14.555374] cx88[0]/2: cx2388x based DVB/ATSC card
> [   14.555446] BUG: unable to handle kernel NULL pointer dereference at 00000000
> [   14.555560] IP: [<c02e6bff>] __mutex_lock_common+0x3c/0xe4
> [   14.555652] *pde = 00000000
> [   14.555735] Oops: 0002 [#1] SMP
> [   14.555851] Modules linked in: cx88_dvb(+) cx88_vp3054_i2c videobuf_dvb wm8775 dvb_core tuner_simple tuner_types snd_seq_dummy tda9887 snd_seq_oss(+) snd_intel8x0(+) tda8290 snd_seq_midi snd_seq_midi_event snd_ac97_codec cx88_alsa(+) snd_seq ac97_bus snd_pcm_oss snd_mixer_oss snd_pcm snd_rawmidi snd_timer tuner snd_seq_device psmouse snd serio_raw ivtv(+) cx8800 cx8802 cx88xx soundcore cx2341x ir_common ns558 i2c_i801 v4l2_common videodev i2c_algo_bit gameport v4l1_compat snd_page_alloc tveeprom pcspkr floppy videobuf_dma_sg videobuf_core btcx_risc i2c_core parport_pc parport button intel_agp agpgart shpchp pci_hotplug rng_core iTCO_wdt sd_mod evdev usbhid hid ff_memless ext3 jbd mbcache ide_cd_mod cdrom ide_disk ata_piix libata dock 8139too usb_storage scsi_mod piix 8139cp mii ide_core uhci_hcd ehci_hcd usbcore thermal processor fan thermal_sys
> [   14.557013]
> [   14.557013] Pid: 2310, comm: modprobe Not tainted (2.6.27.1-custom-default1 #1)
> [   14.557013] EIP: 0060:[<c02e6bff>] EFLAGS: 00010246 CPU: 1
> [   14.557013] EIP is at __mutex_lock_common+0x3c/0xe4
> [   14.557013] EAX: de653e98 EBX: de739118 ECX: de739120 EDX: 00000000
> [   14.557013] ESI: dd4209e0 EDI: de73911c EBP: de653eb0 ESP: de653e88
> [   14.557013]  DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
> [   14.557013] Process modprobe (pid: 2310, ti=de652000 task=dd4209e0 task.ti=de652000)
> [   14.557013] Stack: 3535352e 5d343733 00000002 de739120 de739120 00000000 c044a6c0 de739110
> [   14.557013]        de739118 00000001 de653ebc c02e6d38 c02e6b88 de653ec4 c02e6b88 de653ed8
> [   14.557013]        e1ac7115 de6a9000 00000001 00000000 de653f0c e1aeca62 de739004 de739000
> [   14.557013] Call Trace:
> [   14.557013]  [<c02e6d38>] ? __mutex_lock_slowpath+0x17/0x1a
> [   14.557013]  [<c02e6b88>] ? mutex_lock+0x12/0x14
> [   14.557013]  [<c02e6b88>] ? mutex_lock+0x12/0x14
> [   14.557013]  [<e1ac7115>] ? videobuf_dvb_get_frontend+0x19/0x40 [videobuf_dvb]
> [   14.557013]  [<e1aeca62>] ? cx8802_dvb_probe+0xc9/0x1945 [cx88_dvb]
> [   14.557013]  [<e09ee41e>] ? cx8802_register_driver+0xbd/0x1ac [cx8802]
> [   14.557013]  [<e09ee467>] ? cx8802_register_driver+0x106/0x1ac [cx8802]
> [   14.557013]  [<e1aee37f>] ? dvb_init+0x22/0x27 [cx88_dvb]
> [   14.557013]  [<c0101132>] ? _stext+0x42/0x11a
> [   14.557013]  [<e1aee35d>] ? dvb_init+0x0/0x27 [cx88_dvb]
> [   14.557013]  [<c013d2ca>] ? __blocking_notifier_call_chain+0xe/0x51
> [   14.557013]  [<c014970b>] ? sys_init_module+0x8c/0x17d
> [   14.557013]  [<c0103b42>] ? syscall_call+0x7/0xb
> [   14.557013]  [<c013007b>] ? round_jiffies_relative+0x14/0x16
> [   14.557013]  =======================
> [   14.557013] Code: 78 04 89 f8 89 55 e0 64 8b 35 00 30 3f c0 e8 2e 0c 00 00 8d 43 08 89 45 e4 8b 53 0c 8d 45 e8 8b 4d e4 89 43 0c 89 4d e8 89 55 ec <89> 02 89 75 f0 83 c8 ff 87 03 48 74 55 8a 45 e0 8b 4d e0 83 e0
> [   14.557013] EIP: [<c02e6bff>] __mutex_lock_common+0x3c/0xe4 SS:ESP 0068:de653e88
> [   14.565211] ---[ end trace 94d8b014e067ac7b ]---

Tested and confirmed to work by several users at linux-media@vger.kernel.org

Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>