Re: [RFC PATCH] char: misc: Init misc->list in a safe way

From: Chunyan Zhang
Date: Thu Jun 29 2017 - 03:30:41 EST


ti

On 29 June 2017 at 15:03, Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> On Thu, Jun 29, 2017 at 02:54:23PM +0800, Chunyan Zhang wrote:
>> Hi Greg,
>>
>> On 28 June 2017 at 19:21, Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>> > On Wed, Jun 28, 2017 at 12:34:28PM +0200, Arnd Bergmann wrote:
>> >> On Wed, Jun 28, 2017 at 7:18 AM, Greg Kroah-Hartman
>> >> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>> >> > On Wed, Jun 28, 2017 at 09:54:32AM +0800, Orson Zhai wrote:
>> >> >> We found the device is "fm". We highly suspect that fm driver call
>> >> >> misc_register twice and reinitialize list to make ->pre & ->next
>> >> >> pointing to himself.
>> >> >>
>> >> >> Meanwhile, we checked fm driver and found nothing obviously wrong in the code.
>> >> >
>> >> > Do you have a pointer to this driver? Is it in the kernel tree?
>> >>
>> >> I found a version of some spreadtrum FM driver in the sources for the
>> >> Samsung Galaxy
>> >> J3, this is the driver https://pastebin.com/p7Y7xQNE
>> >
>> > Ah nice, Orson, is that the driver?
>>
>> For some unknown reason, Orson was missing in this list :)
>> I'm adding him back.
>>
>> This is not the latest version of our FM driver. You can find the
>> version we're using within Spreadtrum here [1], and the kernel version
>> we're using is v4.4.49.
>
> You forgot the link in your footnote, so we can read the code :)

Ah, my mistake :)

[1] https://github.com/sprdlinux/kernel/blob/for-greg/drivers/misc/sprdwcn_bsp/sc2342/radio/fmdrv_ops.c

>
>> > Any objection for me adding it to the kernel tree so we can fix up the
>>
>> We have no objection to adding this driver to the kernel tree.
>
> Great, want me to make up the patch, or do you want to?

How do we have the heart to take your precious time :)
Anyway, we can do that on our own.

Thank you,
Chunyan

>
> thanks,
>
> greg k-h