Re: [PATCH v2] nbd: Don't use workqueue to handle recv work

Yongji Xie
2022-03-22T08:10:16Z

Ping.

Hi Josef, any other comments for this approach.

On Sat, Feb 19, 2022 at 9:04 PM Yongji Xie <xieyongji@bytedance.com> wrote:
>
> On Fri, Feb 18, 2022 at 11:21 PM Josef Bacik <josef@toxicpanda.com> wrote:
> >
> > On Tue, Feb 15, 2022 at 09:17:37PM +0800, Yongji Xie wrote:
> > > Ping again.
> > >
> > > Hi Josef, could you take a look?
> >
> > Sorry Yongji this got lost. Again in the reconnect case we're still setting up
> > a long running thread, so it's not like it'll happen during a normal reclaim
> > path thing, it'll be acted upon by userspace. Thanks,
> >
>
> During creating this long running thread, we might trigger memory
> reclaim since workqueue will use GFP_KERNEL allocation for it. Then a
> deadlock can occur if the memory reclaim happens to hit the page cache
> on this reconnecting nbd device.
>
> Thanks,
> Yongji