Re: [patch] irqlock patch -G3. [was Re: odd memory corruption

[Linus Torvalds]

On Tue, 23 Jul 2002, Andrew Morton wrote:
>
> And yet here we have a case where a spin_unlock() will
> go and turn on local interrupts.  Only with CONFIG_PREEMPT,
> and even then, extremely rarely.

I think that's just a bug, the same way it was a bug that preemtion would
sometimes set tsk->state to TASK_RUNNING.

I think Robert already sent a fix: make "preempt_schedule()" refuse to
schedule if local interrupts are disabled.

That, together with making it a warning (so that we can _fix_ places that
have unbalanced irq/spinlock behaviour) shoul dbe fine. Eventually, if we
think all places are fixed, we can remove the test from
preempt_schedule().

		Linus