[PATCH 3/3] wcn36xx: don't delete invalid bss indices

[Daniel Mack]

On Wednesday, April 04, 2018 07:40 AM, Ramon Fried wrote:
> On 4/3/2018 7:51 PM, Daniel Mack wrote:
>> The firmware code cannot cope with requests to remove BSS indices that have
>> not previously been added. This primarily happens when the device is
>> suspended and then resumed. ieee80211_reconfig() then calls into
>> wcn36xx_bss_info_changed() with an empty bssid and BSS_CHANGED_BSSID set,
>> which subsequently leads to a firmware crash:
>>
>> [   43.647928] qcom-wcnss-pil a204000.wcnss: fatal error received: halMsg.c:4964:halMsg_DelBss: Invalid BSSIndex 0
>> [   43.647959] remoteproc remoteproc0: crash detected in a204000.wcnss: type fatal error
>>
>> To fix this, set bss_index to WCN36XX_HAL_BSS_INVALID_IDX for all bss
>> that have not been configured in the firmware, and don't call into the
>> firmware with invalid indices.
>>
>> Signed-off-by: Daniel Mack <daniel at zonque.org>

> Interesting. I have never seen this bug before.
> Do you have a way of recreating it so I can test it on my side ?

I tested this by putting the machine to suspend with

  # echo freeze >/sys/power/state

right after boot, without connecting to a network before. Resume will
then fail without this patch. I haven't see it in any other cases either
though.


Thanks,
Daniel