Arch Linux User Repository

kelebek333 has a PR to fix 5.18 build

replace 'source' in PKGBUILD with

git+https://github.com/kelebek333/rtl8821CU.git#branch=buildfix-518

Doesn't work with the 5.18 kernel

5.12.0 version has been released in morrownr fork

You need to uninstall the package and then reinstall it. It will then compile, but there is still the message "Deprecated feature: REMAKE_INITRD".

It does not compile anymore with kernel v5.15 /var/lib/dkms/rtl8821cu/5.4.1118f1bc7e8/build/core/rtw_br_ext.c:20:18: fatal error: net/ipx.h: No such file or directory 20 | #include <net/ipx.h>

This is due to kernel commit 6c9b40844751 ("net: Remove net/ipx.h and uapi/linux/ipx.h header files"), merged in v5.15-rc1

Please consider switching to the morrownr fork - the current brektrou fork uses the net/ipx network layer which has been deprecated and removed altogether as of kernel 5.15.3.

I've just reinstalled the driver and it works great with both linux 5.10.47-1-lts and 5.12.14-arch1-1

I suggest you all to upgrade to this newer version.

I followed the advice, but still nothing.

sudo sed -i s/GRO_DROP/GRO_MERGED_FREE/ /usr/src/rtl8821cu-5.4.11202e43634/os_dep/linux/recv_linux.c sudo dkms install -m rtl8821cu -v 5.4.11202e43634 Kernel preparation unnecessary for this kernel. Skipping...

Building module: cleaning build area... 'make' -j4 KVER=5.12.8-arch1-1 KSRC=/lib/modules/5.12.8-arch1-1/build...(bad exit status: 2) Error! Bad return status for module build on kernel: 5.12.8-arch1-1 (x86_64) Consult /var/lib/dkms/rtl8821cu/5.4.11202e43634/build/make.log for more information.

error in log is:

cc1: error: incompatible gcc/plugin versions

Quick fix from upstream bug report for those that need this working asap (will be overwritten on next package update):

# sed -i s/GRO_DROP/GRO_MERGED_FREE/ /usr/src/rtl8821cu-5.4.1118f1bc7e8/os_dep/linux/recv_linux.c
# dkms install -m rtl8821cu -v 5.4.1118f1bc7e8
# modprobe 8821cu

@Ilgaz That package is for a separate upstream repo, which doesn't use DKMS. It's also available in the AUR: https://aur.archlinux.org/packages/rtl8821cu-git/

As for this one, it seems someone went ahead and reported the problem upstream: https://github.com/brektrou/rtl8821CU/issues/132

I am using it under kernel 5.12 on openSUSE TW via this package (perhaps it can help) https://build.opensuse.org/package/show/home%3ASauerland/rtl8821cu

Doesn't seem to compile for kernel 5.12. I'm getting this error:

==> dkms install --no-depmod -m rtl8821cu -v 5.4.1118f1bc7e8 -k 5.12.1-arch1-1
Error! Bad return status for module build on kernel: 5.12.1-arch1-1 (x86_64)
Consult /var/lib/dkms/rtl8821cu/5.4.1118f1bc7e8/build/make.log for more information.

Checking the make.log file, the problem seems to be this:

/var/lib/dkms/rtl8821cu/5.4.1118f1bc7e8/build/os_dep/linux/recv_linux.c: In function ‘napi_recv’:
/var/lib/dkms/rtl8821cu/5.4.1118f1bc7e8/build/os_dep/linux/recv_linux.c:358:55: error: ‘GRO_DROP’ undeclared (first use in this function)

Same error for the linux-zen kernel, which is also on 5.12.1. It still compiles just fine for the LTS kernel (5.10.34-1-lts), so I'm guessing this driver doesn't work with 5.12. Can anyone confirm the issue so it can be reported upstream?

Is there any advantage in using the 5.8.1 version?

@khvalera There was a fix on the repo page. I have updated the PKGBUILD let me know if it's working now

@khvalera Is it specific to this package or it does not work either using the upstream repo directly ?

@riazufila I don't know. Try it and let us know :)

Does this driver work with WPA3 AP?

does not work under armv7h

There is a patch making this dkms module compile&work on Debian and now openSUSE. I tested the patch on openSUSE TW and it works with kernel 5.10.rc5 . see https://github.com/brektrou/rtl8821CU/issues/100#issuecomment-733511163

@simona I am afraid not. I have a kernel supported USB dongle too and it works right after plugging. Realtek does not (it has led too,not lighting).

newer kernel core has it inside?

I have tested Manjaro kernel 5.10.rc4 right now on "testing" branch Intel i5 64bit system. Unfortunately it fails stating "error 10" when switching kernel. I have the git tree locally too and manually trying to build fails too.

Update: Here is the reason why. Unless those API calls change there is a little hope it will work in 5.10

https://github.com/brektrou/rtl8821CU/issues/100#issue-741264469

bug on armv7, attempts to enter /path/to/kernel/headers/build/armv7l; the directory is however /path/to/kernel/headers/build/arm

Also: https://github.com/brektrou/rtl8821CU/issues/85 - not sure if this is packager issue or upstream. - Too busy&tired to dig further...

@Cuiyn There has been an update on https://github.com/brektrou/rtl8821CU. My dongle is working on Linux 5.8.3.

@Ilgaz Thanks

Because it fails to work on Linux 5.8.x, I am using the modified version on https://github.com/mbrysa/rtl8821CU, and this works fine for me on 5.8.1.

I am using the manual/git download dkms version and it fails to compile on Linux 5.8.x which just released to stable. Saying for heads up.

@Skallwar I should note that the error I was getting doesn't stop the driver from working. In fact, I'm using it right now to post this comment. Perhaps I should've mentioned this earlier. So the error doesn't really impact me, I just thought it was interesting that someone else was getting the same error.

@janentikan That's strange, the fork just change the name and version of the driver

@strobelite Try remove your AUR helper cache to force a clean build. If it does not work, provide a log and I will switch to "https://github.com/ctwfei/rtl8821cu" while trying to solve your problem. I don't like to rely on a fork but if there is no option, so be it.

@Skallwar Got the same error as @strobelite, but replacing the repo in the pkgbuild to this https://github.com/ctwfei/rtl8821cu seemed to work.

@strobelite I use both lts and non lts kernel. I updated my kernel to 5.6.4 this morning and all went fine. Please report this upstream, or find an other repo, I will happily change the upstream repo

I'm still getting the same error. I uninstalled the driver with pacman, uninstalled and removed it with dkms, uninstalled dkms itself, re-installed linux and linux-headers with pacman, rebooted, installed dkms and the driver again (at this point, installing the driver gave no errors) and then reinstalled linux and linux-headers again.

After doing all this, I still get the exact same error, and I suspect that diomekes will get it, too, the next time they update their kernel.

@Skallwar have you tried using a non-LTS kernel????

That worked. I uninstalled the driver, updated linux and linux-headers, and re-installed the driver. Thanks.

I don't get this issue, weird. Have you tried to remove the driver, update your kernel and make a clean build ? I can do anything about your issue, maybe be report it on GitHub ? If you find an other repo wich works for you, please let me know

I've been getting the same error as diomekes for the last week or two when I update my kernel. I'll add my DKMS make log the next time I do an update.

@Skallwar http://ix.io/2h4A

@diomekes Can you provide more info on your system ? I can't reproduce your error with both linux 5.6.2-arch1-2 and linux 5.4.30-1-lts

I'm getting an "Error! Bad return status for build on kernel" after yesterday's kernel and headers upgrade. I downgraded the headers and it works fine.

@bsosenba Done, thanks to bring that up

The git source you have in the PKGBUILD is no longer maintained. Could you please switch to the master branch of the source tree (https://github.com/brektrou/rtl8821CU)? That one is still being actively developed. I just tested that fork on my machine (kernel 5.8) and it's working well

Yes I would like that! It may help me learn a bit more and I have a USB dongle that has this chipset.

Since nariox disowned the package, I have taken ownership of it. I can add you to the co-maintainers list if you want.

I would be interested in being a maintainer for this module.

I haven't really used this module in a bit, anyone wants to become maintainer?

@nariox Perhaps it is better to switch to this fork? https://github.com/brektrou/rtl8821CU

It supports kernel up to version 5.5

@mkaczanowski, see if it works for you. (;

I just built module on a few arm boards and it seems to work fine. Can you add armv7h to supported architectures?

The problem is upstream. There's not much I can do. It seems the patch for 5.4 was released recently. Maybe you can try rebuilding the driver.

Does it work for you guys after the latest kernel update ? It's just not detecting the adapter anymore. It used to work until a day ago. I couldn't debug it as the PC is with my dad. Anybody facing it?

It works again, thanks for your efforts!

@aufkrawall: I've changed the git repo to one that supports kernel 5.3. See if it works for you.

The problem is upstream. Sorry, can't do much about it. You can use linux-lts for the time-being.

There is no error output while installing/compiling the DKMS module for linux 5.3, but it doesn't work regardless.

@nariox Update working on my side, check your inbox :)

Hi @nariox I am working on it

Hi @ESTBLC,

could you modify the new PKGBUILD? I don't think I have time to test out and deploy a new version in the coming weeks. I am using this in a raspberry pi, but I didn't see support for it in this repo, so that was one of the draws to the current repo, but it seems whitebatman2 has gone AWOL. If you post a new PKGBUILD, I'll add it, then I can probably send a merge request to add the pi's to brektrou's repo.

I recommand switching to this repo since it works out of the box: https://github.com/brektrou/rtl8821CU

Thank you very much, modifying: /usr/src/rtl8821cu-5.2.5.3_24795.20171031.r18.g0278eaa/os_dep/linux/ioctl_cfg80211.c with the patch you posted, the issue is gone.

@barmaley: yes. Kernel 4.20 deprecated one of the functions used by the driver. This has been reported here: https://github.com/whitebatman2/rtl8821CU/issues/12

A patch has been submitted, but not yet merged. In the meantime, you have to change a two lines in the code as shown here: https://github.com/whitebatman2/rtl8821CU/pull/14/commits/adb329bdae3d634550660d17af8d98d67b43d483#diff-c39a0cc7e3701496c432e2cfe95097ba

Hi, this module does not build in my systems: attaching make.log

https://hastebin.com/dorozikohu.cs

Thanks and best regards

You're very welcome. I'm glad to help other Arch users (: I should be able to modify this script to work for armv7h and armv8 boards, but I haven't had any time to work on it. A big thanks to whitebatman2 as well for maintaining the github repo.

Thank you for your effort in providing this driver!