On Sun, May 19, 2013 at 07:40:09PM +0300, Michael S. Tsirkin wrote: > OK I get it. So let me correct myself. The simple code > that does something like this under a spinlock: > > preempt_disable > > pagefault_disable > > error = copy_to_user > > pagefault_enable > > preempt_enable > > > is not doing anything wrong and should not get a warning, > as long as error is handled correctly later. > Right? Indeed, but I don't get the point of the preempt_{disable,enable}() here. Why does it have to disable preemption explicitly here? I thought all you wanted was to avoid the pagefault handler and make it do the exception table thing; for that pagefault_disable() is sufficient. -- 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>