On Sun, 2013-05-19 at 12:35 +0300, Michael S. Tsirkin wrote: > No, I was not assuming that. What I'm trying to say is that a caller > that does something like this under a spinlock: > preempt_disable > pagefault_disable > error = copy_to_user > pagefault_enable > preempt_enable_no_resched > > is not doing anything wrong and should not get a warning, > as long as error is handled correctly later. > Right? > What I see wrong with the above is the preempt_enable_no_resched(). The only place that should be ever used is right before a schedule(), as you don't want to schedule twice (once for the preempt_enable() and then again for the schedule itself). Remember, in -rt, a spin lock does not disable preemption. -- Steve -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>