On Wed, Oct 08, 2014 at 05:57:50PM +0200, Kristof Provost wrote:
On 2014-10-08 21:14:43 (+0530), Jeshwanth Kumar N K <jeshkumar555@gmail.com> wrote:
Wayback when I was working on some project to wake up userspace program for every rising edge in GPIO pin (hall sensor), I use to send signal to the PID from kernel, before that userspace has to register its PID with kernel module.
I've seen a certain vendor[1] do something similar. They saved the task pointer for whichever process made the magical ioctl() call and used it to send signals from the interrupt handler. It worked, right up to the point where the process went away and then the kernel panicked.
Exactly, don't do that :) Finding out the real problem that is attempting to be solved would be good... greg k-h