On Thu, Mar 30, 2017 at 01:27:19PM +0300, Andrey Ryabinin wrote:
> vfree() can be used in any atomic context and there is no
> vfree_atomic() callers left, so let's remove it.
We might still get warnings though.
> @@ -1588,9 +1556,11 @@ void vfree(const void *addr)
>
> if (!addr)
> return;
> - if (unlikely(in_interrupt()))
> - __vfree_deferred(addr);
> - else
> + if (unlikely(in_interrupt())) {
> + struct vfree_deferred *p = this_cpu_ptr(&vfree_deferred);
> + if (llist_add((struct llist_node *)addr, &p->list))
> + schedule_work(&p->wq);
> + } else
> __vunmap(addr, 1);
> }
> EXPORT_SYMBOL(vfree);
If I disable preemption, then call vfree(), in_interrupt() will not be
true (I've only incremented preempt_count()), then __vunmap() calls
remove_vm_area() which calls might_sleep(), which will warn.
So I think this check needs to change from in_interrupt() to in_atomic().
