Re: brcmfmac: Fix kernel oops on resume when request firmware fails.

From: Arend van Spriel
Date: Tue Jun 13 2017 - 06:58:34 EST


On 13-06-17 12:23, Enric Balletbo Serra wrote:
> Hello Kalle,
>
> 2017-06-13 7:54 GMT+02:00 Kalle Valo <kvalo@xxxxxxxxxxxxxx>:
>> Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx> wrote:
>>
>>> When request firmware fails, brcmf_ops_sdio_remove is being called and
>>> brcmf_bus freed. In such circumstancies if you do a suspend/resume cycle
>>> the kernel hangs on resume due a NULL pointer dereference in resume
>>> function.
>>>
>>> Steps to reproduce the problem:
>>> - modprobe brcmfmac without the firmware
>>> brcmfmac mmc1:0001:1: Direct firmware load for brcm/brcmfmac4354-sdio.bin
>>> failed with error -2
>>> - do a suspend/resume cycle (echo mem > /sys/power/state)
>>>
>>> Protect against the NULL pointer derefence by checking if dev_get_drvdata
>>> returned a valid pointer.
>>>
>>> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
>>
>> My understanding is that there's a new version of this patch which fixes
>> the issue. If not, let me know.
>>
>> Patch set to Superseded.
>>
>
> Yes there are these patch series [1] that fixes the issue, I guess
> Arend is working on a v2 to fix a small issue we found.
>
> [1] https://www.spinics.net/lists/linux-wireless/msg162762.html

That series was actually RFT so not a formal submit. I send out a series
yesterday, which indeed has the small issue fixed [2].

Regards,
Arend

[2] https://patchwork.kernel.org/patch/9780793/

>> --
>> https://patchwork.kernel.org/patch/9743159/
>>
>> https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
>>
>
> Regards,
> Enric
>