Open jolivain opened 2 years ago
@jolivain :
Thanks for your feedback.
We did see error log after rmmod
then attempting modprobe wlan
module driver.
But we don't see system hanging after rmmod wlan
module driver.
Test steps:
wlan
driver.In arch/arm64/boot/dts/freescale/imx8mm-pico.dtsi, under kernel source code:
WIFI SDIO is configured as non-removable
devices.
/* WIFI SDIO */
&usdhc1 {
pinctrl-names = "default", "state_100mhz", "state_200mhz";
pinctrl-0 = <&pinctrl_usdhc1>;
pinctrl-1 = <&pinctrl_usdhc1_100mhz>;
pinctrl-2 = <&pinctrl_usdhc1_200mhz>;
bus-width = <4>;
no-1-8-v;
vmmc-supply = <&wl_reg_on>;
pm-ignore-notify;
keep-power-in-suspend;
non-removable;
status = "okay";
};
I guess It would need to trigger mmc driver to rescan bus once the driver is reloaded.
BR,
Richard
Hi Richard,
Thank you for testing.
On my end, I see the same as you: doing "rmmod wlan" alone on a started Yocto system does not freeze the system.
To crash the system, I also need to stop connman before unloading wlan, with the two commands:
systemctl stop connman
rmmod wlan
The same crash is reproduced when systemd is not started at all. To do so, interrupt the U-Boot autoboot by hitting a key, add "init=/bin/sh" in mmc boot args, then boot:
setenv mmcargs ${mmcargs} init=/bin/sh
boot
The bash prompt will show, and the system freezes about 5 seconds later.
For information, I use a bare imx8mm-pico-pi board, with only USB-C power and USB uart connected. (No display, no hat, etc.)
Best regards,
Julien.
Hi Richard,
Some more info:
With the xwayland image you provided (imx-image-full-pico-imx8mm-20211018151521), I cannot always reproduce the issue with the "rmmod wlan": it seems some other user space processes are hiding the issue (most likely connman, hciattach). When writing my initial report, I was using a core-image-minimal Yocto image from imx-5.4.70-2.3.0_2021Q4.
Adding "init=/bin/sh" to kernel boot args always trigger the issue on your image. It seems the most reliable way to trigger the issue.
Note: I'm also able to reproduce the same issue with components from the branch tn-imx_5.10.52_2.1.0-next: Kernel on commit 486b33f92ecdb27ac4959e5cc39dde2213339cfc U-Boot on commit e57a84b6944d55e7748ef6d09afbf4f3b4a131f7
Thanks,
Julien.
How to reproduce:
Environment:
Board imx8mm pico pi: https://www.technexion.com/products/system-on-modules/evk/pico-pi-imx8m-mini/
Starting from Yocto BSP:
tx-imx-yocto-manigest is on commit 86721af835feb1e3ad9ed843c8708c128409acf8, at the time of this writing. Kernel tag: tn-zeus_5.4.70-2.3.0_20211018
Step 1: run the system without wlan.ko:
Option 1: Add "init=/bin/sh" in Kernel boot args
Option 2: On a normally started system, login as root, then unload wlan.ko with commands:
Actual result
system hang after few seconds. The hang can be avoided the first time, by running "modprobe wlan" before the hang. Note: further unloading/reloading wlan.ko seems to crash for other reasons.
Expected result
system should be usable even if the wlan.ko module is not loaded. Ideally, wlan.ko unloading/reloading should work too.