On Mon, Apr 11, 2022 at 11:06 AM Bart Van Assche <bvanassche@xxxxxxx> wrote:
>
> On 4/10/22 15:39, Bob Pearson wrote:
> > Fixes: 3225717f6dfa ("RDMA/rxe: Replace red-black trees by carrays")
> ^^^^^^^
> xarrays?
>
> > @@ -138,8 +140,10 @@ void *rxe_alloc(struct rxe_pool *pool)
> > elem->obj = obj;
> > kref_init(&elem->ref_cnt);
> >
> > - err = xa_alloc_cyclic(&pool->xa, &elem->index, elem, pool->limit,
> > + xa_lock_irqsave(xa, flags);
> > + err = __xa_alloc_cyclic(&pool->xa, &elem->index, elem, pool->limit,
> > &pool->next, GFP_KERNEL);
> > + xa_unlock_irqrestore(xa, flags);
>
> Please take a look at the xas_unlock_type() and xas_lock_type() calls in
> __xas_nomem(). I think that the above change will trigger a GFP_KERNEL
> allocation with interrupts disabled. My understanding is that GFP_KERNEL
> allocations may sleep and hence that the above code may cause
> __xas_nomem() to sleep with interrupts disabled. I don't think that is
> allowed.
Thanks. I will send V2.
Zhu Yanjun
>
> Thanks,
>
> Bart.
