Received-SPF: pass (google.com: domain of linux-wireless-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Sender: Larry Finger <larry.finger@gmail.com>
Subject: Re: RTL8821CE 802.11ac PCIe Wireless Network Adapter - Not handled
 properly by the rtw_8821ce dirver on Kernel 5.11.6-1
To:     Michal TOMA <michaltoma@sicoop.com>, linux-wireless@vger.kernel.org
References: <2846955.Y2WTrdj9rP@linux-9g0r.site>
From:   Larry Finger <Larry.Finger@lwfinger.net>
Message-ID: <b9ea29a4-675f-6fec-954e-2878e2e8285f@lwfinger.net>
Date:   Fri, 26 Mar 2021 10:18:18 -0500
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101
 Thunderbird/78.8.1
MIME-Version: 1.0
In-Reply-To: <2846955.Y2WTrdj9rP@linux-9g0r.site>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 3/26/21 7:16 AM, Michal TOMA wrote:
> The RTL8821CE driver doesn't work on several recent kernels (probably since
> 5.9).
> 
> 
> journalctl -b | grep 8821
> mars 19 22:49:13 localhost kernel: rtw_8821ce 0000:07:00.0: Firmware version
> 24.8.0, H2C version 12
> mars 19 22:49:13 localhost NetworkManager[639]: <info>  [1616190553.7766]
> rfkill2: found Wi-Fi radio killswitch (at
> /sys/devices/pci0000:00/0000:00:1d.4/0000:07:00.0/ieee80211/phy0/rfkill2)
> (driver rtw_8821ce)
> mars 19 22:49:13 localhost kernel: rtw_8821ce 0000:07:00.0 wlp7s0: renamed
> from wlan0
> mars 19 22:49:14 localhost kernel: rtw_8821ce 0000:07:00.0: start vif
> 28:39:26:ab:b4:5d on port 0
> mars 19 22:49:14 localhost kernel: rtw_8821ce 0000:07:00.0: stop vif
> 28:39:26:ab:b4:5d on port 0
> mars 19 22:49:14 localhost kernel: rtw_8821ce 0000:07:00.0: start vif
> 7a:36:c4:26:1d:f1 on port 0
> mars 19 22:56:07 linux.local kernel: rtw_8821ce 0000:07:00.0: stop vif
> 7a:36:c4:26:1d:f1 on port 0
> mars 19 22:56:07 linux.local kernel: rtw_8821ce 0000:07:00.0: start vif
> c2:a0:c3:48:17:58 on port 0
> mars 19 23:03:00 linux.local kernel: rtw_8821ce 0000:07:00.0: stop vif
> c2:a0:c3:48:17:58 on port 0
> mars 19 23:03:00 linux.local kernel: rtw_8821ce 0000:07:00.0: start vif
> ae:92:06:47:50:83 on port 0
> mars 19 23:09:52 linux.local kernel: rtw_8821ce 0000:07:00.0: stop vif
> ae:92:06:47:50:83 on port 0
> ...
> And continues like this indefinitely
> 
> uname -a
> Linux linux.local 5.11.6-1-default #1 SMP Thu Mar 11 16:11:36 UTC 2021
> (7358b30) x86_64 x86_64 x86_64 GNU/Linux
> 
> rfkill list
> 0: ideapad_wlan: Wireless LAN
>          Soft blocked: no
>          Hard blocked: no
> 1: ideapad_bluetooth: Bluetooth
>          Soft blocked: no
>          Hard blocked: no
> 2: phy0: Wireless LAN
>          Soft blocked: no
>          Hard blocked: no
> 

I want to add a bit to this report as I have been helping Michal on an openSUSE 
bugzilla thread. His driver comes from my repo at 
https://GitHub.com/lwfinger/rtw88.git. That code corresponds to wireless-next 
with fixes for kernel API changes. The repo provides 8822ce code that works 
perfectly on my machine.

I do not have an 8821ce cdhip, thus I cannot verify this directly. What would be 
helpful is for the Realtek devs to suggest debug parameters that would yield 
information as to why the driver does not attempt to authenticate, but 
immediately stops the vif.

Thanks,

Larry