9f02b8f61f
If the kernel is compiled with CONFIG_PREEMPT_VOLUNTARY and OP-TEE is executing a long running workload, the following errors are raised: [ 1705.971228] rcu: INFO: rcu_sched detected stalls on CPUs/tasks: [ 1705.977195] rcu: (detected by 0, t=2102 jiffies, g=51977, q=3) [ 1705.983152] rcu: All QSes seen, last rcu_sched kthread activity 2102 (140596-138494), jiffies_till_next_fqs=1, root ->qsmask 0x0 [ 1705.994729] optee-xtest R running task 0 169 157 0x00000002 While OP-TEE is returning regularly to the kernel due to timer interrupts, the OPTEE_SMC_FUNC_FOREIGN_INTR case does not contain an explicit rescheduling point. Add a might_sleep() to the RPC request case to ensure that the kernel can reschedule another task if OP-TEE requests RPC handling. Signed-off-by: Rouven Czerwinski <r.czerwinski@pengutronix.de> Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
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.