Fabio Estevam
019edd01d1
On a i.MX-based board with a QCA9377 Wifi chip, the following errors are seen after launching the 'hostapd' application: hostapd /etc/wifi.conf Configuration file: /etc/wifi.conf wlan0: interface state UNINITIALIZED->COUNTRY_UPDATE NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!! Using interface wlan0 with hwaddr 00:1f:7b:31:04:a0 and ssid "thessid" IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready wlan0: interface state COUNTRY_UPDATE->ENABLED wlan0: AP-ENABLED NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!! NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!! NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!! NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!! ... Fix this problem by adding the BH locking around napi-schedule(), in the same way it was done in commite63052a5dd("mlx5e: add add missing BH locking around napi_schdule()"). Its commit log provides the following explanation: "It's not correct to call napi_schedule() in pure process context. Because we use __raise_softirq_irqoff() we require callers to be in a context which will eventually lead to softirq handling (hardirq, bh disabled, etc.). With code as is users will see: NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!! " Fixes:cfee8793a7("ath10k: enable napi on RX path for sdio") Signed-off-by: Fabio Estevam <festevam@denx.de> Signed-off-by: Kalle Valo <kvalo@codeaurora.org> Link: https://lore.kernel.org/r/20210824144339.2796122-1-festevam@denx.de
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.