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Re: Sleeping after preempt_disable() possible?

Rick Brown wrote:

I was curious that after a call to preempt_disable(), can I call a
function that MAY sleep?

Bad idea. That can make the kernel do bad things...

Just take a look at schedule() in kernel/sched.c:

asmlinkage void __sched schedule(void)
{
...
	if (unlikely(in_atomic() && !current->exit_state)) {
                printk(KERN_ERR "BUG: scheduling while atomic: "
                        "%s/0x%08x/%d\n",
                        current->comm, preempt_count(), current->pid);
                dump_stack();
        }

Of course, in_atomic() checks whether you disabled preemption.

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