RE: [PATCH] iommu/iova: Free all CPU rcache for retry when iova alloc failure

From: yf.wang
Date: Sun Mar 06 2022 - 22:55:44 EST


On Fri, 2022-03-04 at 14:03 +0000, Robin Murphy wrote:
>
> OK, so either there's a mystery bug where IOVAs somehow get freed on
> offline CPUs, or the hotplug notifier isn't working correctly, or
> you've
> contrived a situation where alloc_iova_fast() is actually racing
> against
> iova_cpuhp_dead(). In the latter case, the solution is "don't do
> that".
>
> This change should not be necessary.
>
> Thanks,
> Robin.

Hi Robin,

You are right, kernel 5.15 already has this patch, but kernel 5.10
not contain.

Thanks,
Yunfei.