Description of problem: printk calls consol functions that write to the appropriate devices. But in the PREEMPT_RT kernel, some of these console functions grab spin locks that are converted to mutexes. This means that calling printk in an atomic operation or from interrupt contex can schedule and cause undefined results. Version-Release number of selected component (if applicable): How reproducible: Steps to Reproduce: 1. 2. 3. Actual results: Expected results: Additional info: I need to write a patch that will add an ATOMIC_SAFE flag to the console drivers. This will be checked if printk is called from an atomic operation. If the console is not safe, then printk will skip that console. Current consoles that should be atomic safe, is the VGA console as well as early_printk console.
Patch applied