wlan0 is not present after updating kernel to 5.6.0-rc7

[aronfeher]

Hi!

I've started a new issue, since The last one (the header problem) was solved, but a new issue arose, which was different.

I've downloaded torvalds kernel 5.6.0-rc7, and built the complete image with my modules, and headers. I've installed the zImage, modules and linux headers. I've installed the device tree as you stated at the build your own kernel section.

When I restarted the BPI everything was seemingly OK - I did not try the WiFi at this stage, so I modified the device tree to have the PWM, SPI, I2C modules, which were present after the restart.

The problem is now wlan0 won't appear. At boot-up the system failes to start DHCP Client, and fails to Raise network interfaces. ifconfig shows only eth0 and lo. Writing ifup wlan0 gives:

wpa_supplicant: /sbin/wpa_supplicant daemon failed to start
run-parts: /etc/network/if-pre-up.d/wpasupplicant exited with return code 1
ifup: failed to bring up wlan0

Do I have to change something in the Kernel, or the Device Tree? Or something after the build?

[avafinger]

Use this kernel: https://github.com/avafinger/linux-5.6.y

[aronfeher]

Ok, I've downloaded the kernel. git tag -l | less Returned nothign, so I presume it's the latest rc7. After make -j4 sunxi_defconfig the configuration was written, but two warnings arose:

drivers/mtd/devices/Kconfig:212:warning: config symbol defined without type drivers/mtd/devices/Kconfig:214:warning: config symbol defined without type and the instruction make INSTALL_MOD_PATH=output zImage can't complete because of some scripts/mod/devicetable-offsets.c errors - the last few lines are: scripts/mod/devicetable-offsets.c:228:2: note: in expansion of macro ‘DEVID’ 228 | DEVID(tee_client_device_id); | ^~~~~ scripts/mod/devicetable-offsets.c:5:50: error: invalid application of ‘sizeof’ to incomplete type ‘struct tee_client_device_id’ 5 | #define DEVID(devid) DEFINE(SIZE_##devid, sizeof(struct devid)) | ^~~~~~ scripts/mod/devicetable-offsets.c:228:2: note: in expansion of macro ‘DEVID’ 228 | DEVID(tee_client_device_id); | ^~~~~ scripts/mod/devicetable-offsets.c:7:9: error: ‘OFF_tee_client_device_id_uuid’ undeclared (first use in this function); did you mean ‘tee_client_device_id’? 7 | DEFINE(OFF_##devid##_##field, offsetof(struct devid, field)) | ^~~~ scripts/mod/devicetable-offsets.c:229:2: note: in expansion of macro ‘DEVID_FIELD’ 229 | DEVID_FIELD(tee_client_device_id, uuid); | ^~~~~~~~~~~ scripts/mod/devicetable-offsets.c:7:41: error: expected expression before ‘struct’ 7 | DEFINE(OFF_##devid##_##field, offsetof(struct devid, field)) | ^~~~~~ scripts/mod/devicetable-offsets.c:229:2: note: in expansion of macro ‘DEVID_FIELD’ 229 | DEVID_FIELD(tee_client_device_id, uuid); | ^~~~~~~~~~~ scripts/mod/devicetable-offsets.c:5:29: error: ‘SIZE_wmi_device_id’ undeclared (first use in this function); did you mean ‘fsl_mc_device_id’? 5 | #define DEVID(devid) DEFINE(SIZE_##devid, sizeof(struct devid)) | ^~~~~ scripts/mod/devicetable-offsets.c:231:2: note: in expansion of macro ‘DEVID’ 231 | DEVID(wmi_device_id); | ^~~~~ scripts/mod/devicetable-offsets.c:5:50: error: invalid application of ‘sizeof’ to incomplete type ‘struct wmi_device_id’ 5 | #define DEVID(devid) DEFINE(SIZE_##devid, sizeof(struct devid)) | ^~~~~~ scripts/mod/devicetable-offsets.c:231:2: note: in expansion of macro ‘DEVID’ 231 | DEVID(wmi_device_id); | ^~~~~ scripts/mod/devicetable-offsets.c:7:9: error: ‘OFF_wmi_device_id_guid_string’ undeclared (first use in this function) 7 | DEFINE(OFF_##devid##_##field, offsetof(struct devid, field)) | ^~~~ scripts/mod/devicetable-offsets.c:232:2: note: in expansion of macro ‘DEVID_FIELD’ 232 | DEVID_FIELD(wmi_device_id, guid_string); | ^~~~~~~~~~~ scripts/mod/devicetable-offsets.c:7:41: error: expected expression before ‘struct’ 7 | DEFINE(OFF_##devid##_##field, offsetof(struct devid, field)) | ^~~~~~ scripts/mod/devicetable-offsets.c:232:2: note: in expansion of macro ‘DEVID_FIELD’ 232 | DEVID_FIELD(wmi_device_id, guid_string); | ^~~~~~~~~~~ cc1: some warnings being treated as errors make[1]: *** [scripts/Makefile.build:101: scripts/mod/devicetable-offsets.s] Error 1 make: *** [Makefile:1112: prepare0] Error 2

[avafinger]

Can you compare the scripts/mod (this kernel) and scripts/mod (from the Linus you just compiled successfully?)

[aronfeher]

I've run a file compare, and no differences were found. I've checked them visually, they are the same.

[aronfeher]

Update. I couldn't build the kernel because of some configs. I've made a clean clone of your linux-5.6.y kernel. Left the default sun8i_defconfig, and I could generate every file. After reboot I get the same problem: A start job is running for network interfaces, and DHCP Client. Both of the jobs fail. Only eth0, and lo.

Another try with a fresh, clean SD card. I've installed linux-5.3.18 with the given image, and updated it to 5.6.0-rc5+ with the .deb file. So far the wlan0 was present. I've downloaded the linux-5.6.y kernel, built it (only the default build, so that I don't have more unknown variables), installed it, and the wlan0 is no more.

[aronfeher]

Do you have an image of the linux-5.6.y with working wlan0, so that I could compare the generated files, because I still couldn't figure out the issue with my build.

[avafinger]

I will build one with 5.6.6 server. You can install Desktop or use it for building kernels.

[aronfeher]

Hi again! Sorry for the continuous bother, but I'm still having the same issues. I download the deb package for the linux-5.6.13-server. and I install it. The system can connect to the Internet, but I can't build kernel modules, since the /usr/lib/modules/build is inaccessible - in ssh it shows up red.

I download the linux-5.6.13 from the official web site. I build it, and place the zImage, dtb, usr files to the correct locations (in this case the /usr/lib/modules/build is accessible and is shown blue), but the wifi disappears. ifup gives the same message as above.

I even tried to use the 5.6.13 src and lib folders with the 5.6.13-server kernel, but that is not working because the kernel differs.

Could you please write the exact kernel number which was used to generate the linux-5.6.13-server, or a download location? As things are I'm starting to feel like dropping the BPi and using an ESP32 where I can control the hardware, and have internet access :)).

[avafinger]

It is 5.6.3. Before you build your kernel, type this: export LOCALVERSION="-server" , so you can build your modules and use it with the pre-built one.

If you build your own kernel from https://www.kernel.org/ it should boot but you have to enable BRCM (wifi):

CONFIG_WLAN=y
CONFIG_WLAN_VENDOR_BROADCOM=y
CONFIG_B43=m
CONFIG_B43_BCMA=y
CONFIG_B43_SSB=y
CONFIG_B43_BUSES_BCMA_AND_SSB=y
CONFIG_B43_SDIO=y
CONFIG_B43_BCMA_PIO=y
CONFIG_B43_PIO=y
CONFIG_B43_PHY_G=y
CONFIG_B43_PHY_N=y
CONFIG_B43_PHY_LP=y
CONFIG_B43_PHY_HT=y
CONFIG_B43_LEDS=y
CONFIG_B43LEGACY=m
CONFIG_B43LEGACY_LEDS=y
CONFIG_B43LEGACY_DEBUG=y
CONFIG_B43LEGACY_DMA=y
CONFIG_B43LEGACY_PIO=y
CONFIG_B43LEGACY_DMA_AND_PIO_MODE=y
CONFIG_BRCMUTIL=m
CONFIG_BRCMFMAC=m
CONFIG_BRCMFMAC_PROTO_BCDC=y
CONFIG_BRCMFMAC_SDIO=y

That will do the trick.

[aronfeher]

Okay. Now I get it. I was missing those CONFIG_B43 settings. For some reason I couldn't (and still can't) find them in menuconfig. After adding them manually the wlan0 reappeared, and now I can use the kernel modules and the wifi. Well this was a nice learning experience.

Thank you very much for this invaluable help!