kthread | Killable threads in Python | Architecture library

The second argument of the function kthread_create() is void *data. Right now you are passing NULL, you can pass your pointer to the struct i2c_client instead. Then you can do:

It's make not found error. Try sudo apt-get install build-essential

it contains make, gcc, ... any other necessary stuff.

The following piece of code might help.

(This answer corresponds to Linux kernel version 5.4.)

The newly created kernel thread task executes the function kthread in "kernel/kthread.c". If all is well kthread calls the thread function referred to by the kthread_run's (or kthread_create's) threadfn parameter. However, the final test before calling the threadfn function pointer is to check the kernel thread's KTHREAD_SHOULD_STOP bit. If the KTHREAD_SHOULD_STOP bit is set, the threadfn function pointer will not be called and the new kernel thread task will call do_exit with the exit code -EINTR. The relevant piece of code at the end of function kthread is as follows:

Your Makefile is wrong. In order to build a kernel module, you need to pass M=, not SUBDIRS=. This should work:

It looks like the problem was introduced by the patch: regulator: stpmic1: Usb boost over-current protection workaround.

• The "boost" interrupt handler stpmic1_boost_irq_handler calls regulator_lock(usb_data->boost_rdev);
• The "boost" interrupt handler (stpmic1_boost_irq_handler) is set up by the stpmic1_boost_register function, but usb_data->boost_rdev is still null at this time.
• usb_data->boost_rdev is set to the return value of the stpmic1_boost_register function by thestpmic1_regulator_probe function.
• If the "boost" interrupt handler stpmic1_boost_irq_handler gets called before usb_data->boost_rdev has been set by the stpmic1_regulator_probe function, then the crash occurs.

A workaround would be to set usb_data->boost_rdev = rdev; in the stpmic1_boost_register function after it has set rdev but before it sets up the interrupt handler.

This should be reported to the author of the patch. See the "Signed-off-by:" line in the patch for the email address.

That's an easy one. Near the top are these:

For correctly operate, your kthread should check "stop" status of the thread when waiting on semaphore. Unfortunately, there is no "stoppable" version of down function.

Instead of kthread use workqueue mechanism. Works already have all features you need:

• You can add a work inside interrupt handler (queue_work),
• Only a single work can be run at the same time,
• Using destroy_workqueue you can safetly finalize all works.

Actually, workqueues are implemented using kthreads. See e.g. implementation of kthread_worker_fn function.

The linker has no business finding macros. Macros are handled by the preprocessor, which runs long before the linker. If the linker is complaining about an undefined reference it means your macro expansion went wrong. It emits KERNEL_THREAD_SAVED_KERNEL_TOP_OFFSET where it shouldn't have.

The issue is with