Hi all, I was under the impression that it is ok to use printk in interrupt handlers. I tried to use printk in some scheduling code (which, if I am not mistaken, is called on return from the local APIC timer interrupt handler). Unfortunately, this deadlocks my system. A one line message appears (recursive spin lock on CPU\1, with different processes as current when it happens). I have compiled in deplock, locking self-tests, and almost every other self-test found in the Removing the printk statement from the scheduler completely fixes the observed behavior, the system is usable and runs stable. This has been observed on 2.6.20-rc7. Previously, on 2.6.9, we also were never able to use printk inside scheduling code because it led to lock-ups (without output). I tried grep-ing through $SRC/Documentation for printk and also tried to google for printk guidelines, but could not find anything. Is it wrong to use printk inside scheduling code? Thanks, Björn -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
