Re: [2.6.16] saa7134 disable_ir oops

[David Liontooth <liontooth@cogweb.net>]

Sergey Vlasov wrote:
> On Fri, 24 Mar 2006 14:00:46 -0800 David Liontooth wrote:
>
>   
>> On 2.6.16 mainline, I get an oops when inserting the saa7134 module with 
>> the option "disable_ir=1", whether for a single card or several.
>>
>> Gigabyte K8NS Ultra-939, LifeView FlyVideo-3000FM NTSC, athlon64 x2 
>> 3800+, Debian sid. All four cards work great otherwise. The new 
>> saa7134-alsa does not appear to be involved in the oops.
>>
>> Issued:
>>
>> sudo modprobe saa7134 card=2,2,2,2 tuner=43,43,43,43 video_nr=1,2,3,4
>> vbi_nr=1,2,3,4 radio_nr=1,2,3,4 alsa=1,1,1,1 disable_ir=1,1,1,1
>> sudo modprobe saa7134-alsa index=1,2,3,4
>>
>> Got in dmesg:
>>
>> Unable to handle kernel NULL pointer dereference at 0000000000000260 RIP:
>> <ffffffff880d5a95>{:saa7134:saa7134_initdev+1452}
>> PGD 3e607067 PUD 3b0b6067 PMD 0
>> Oops: 0000 [1] SMP
>> CPU 0
>> Modules linked in: saa7134 video_buf compat_ioctl32 v4l2_common
>> v4l1_compat ir_kbd_i2c ir_common videodev xfs exportfs snd_intel8x0
>> snd_ac97_codec snd_ac97_bus snd_pcm snd_timer snd soundcore sk98lin
>> snd_page_alloc psmouse pcspkr evdev parport_pc parport ehci_hcd
>> i2c_nforce2 ohci_hcd i2c_core unix
>> Pid: 7134, comm: modprobe Not tainted 2.6.16 #1
>> RIP: 0010:[<ffffffff880d5a95>]
>> <ffffffff880d5a95>{:saa7134:saa7134_initdev+1452}
>>     
> [skip]
>
> Other people algo get oops with disable_ir=1:
>
> http://lkml.org/lkml/2006/2/20/122
>
> Does the following patch fix things?
>   
The patch fixes the oops -- thank you! Yet the ir modules get loaded in 
spite of the "disable_ir=1" parameter:

# sudo modprobe -vvv saa7134 card=2 tuner=43 disable_ir=1
insmod /lib/modules/2.6.16/kernel/drivers/media/common/ir-common.ko
insmod /lib/modules/2.6.16/kernel/drivers/media/video/ir-kbd-i2c.ko
insmod /lib/modules/2.6.16/kernel/drivers/media/video/video-buf.ko
insmod /lib/modules/2.6.16/kernel/drivers/media/video/saa7134/saa7134.ko 
card=2 tuner=43 disable_ir=1

David
> ---
>
> saa7134: Fix oops with disable_ir=1
>
> When disable_ir=1 parameter is used, or when saa7134_input_init1()
> fails for any other reason, dev->remote will remain NULL, and the
> driver will oops in saa7134_hwinit2().  Therefore dev->remote must be
> checked before dereferencing.
>
> Signed-off-by: Sergey Vlasov <vsu@altlinux.ru>
>
> --- linux-2.6.16.orig/drivers/media/video/saa7134/saa7134-core.c	2006-03-20 08:53:29 +0300
> +++ linux-2.6.16/drivers/media/video/saa7134/saa7134-core.c	2006-04-06 20:00:56 +0400
> @@ -543,6 +543,8 @@ static irqreturn_t saa7134_irq(int irq, 
>  		if (report & SAA7134_IRQ_REPORT_GPIO16) {
>  			switch (dev->has_remote) {
>  				case SAA7134_REMOTE_GPIO:
> +					if (!dev->remote)
> +						break;
>  					if  (dev->remote->mask_keydown & 0x10000) {
>  						saa7134_input_irq(dev);
>  					}
> @@ -559,6 +561,8 @@ static irqreturn_t saa7134_irq(int irq, 
>  		if (report & SAA7134_IRQ_REPORT_GPIO18) {
>  			switch (dev->has_remote) {
>  				case SAA7134_REMOTE_GPIO:
> +					if (!dev->remote)
> +						break;
>  					if ((dev->remote->mask_keydown & 0x40000) ||
>  					    (dev->remote->mask_keyup & 0x40000)) {
>  						saa7134_input_irq(dev);
> @@ -671,7 +675,7 @@ static int saa7134_hwinit2(struct saa713
>  		SAA7134_IRQ2_INTE_PE      |
>  		SAA7134_IRQ2_INTE_AR;
>  
> -	if (dev->has_remote == SAA7134_REMOTE_GPIO) {
> +	if (dev->has_remote == SAA7134_REMOTE_GPIO && dev->remote) {
>  		if (dev->remote->mask_keydown & 0x10000)
>  			irq2_mask |= SAA7134_IRQ2_INTE_GPIO16;
>  		else if (dev->remote->mask_keydown & 0x40000)
>
>
>