From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jesper Dangaard Brouer <brouer@redhat.com>
Subject: Re: [bpf-next V5 PATCH 11/15] page_pool: refurbish version of
 page_pool code
Date: Mon, 26 Mar 2018 17:19:38 +0200
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To: Eric Dumazet <eric.dumazet@gmail.com>
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On Fri, 23 Mar 2018 07:55:37 -0700
Eric Dumazet <eric.dumazet@gmail.com> wrote:

> rcu grace period before freeing huge quantitites of pages is
> problematic and could be used by syzbot to OOM the host.

Okay. Adjusted code to empty ring "right-way" when driver calls
destroy, and then only RCU delay/free the page_pool pointer and also
free/empty ring for pages of any in-flight producers.

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer