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Date:   Fri, 10 Nov 2023 15:13:35 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Mina Almasry <almasrymina@google.com>
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arch@vger.kernel.org, linux-kselftest@vger.kernel.org,
        linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org,
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        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
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        Jesper Dangaard Brouer <hawk@kernel.org>,
        Ilias Apalodimas <ilias.apalodimas@linaro.org>,
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        David Ahern <dsahern@kernel.org>,
        Willem de Bruijn <willemdebruijn.kernel@gmail.com>,
        Shuah Khan <shuah@kernel.org>,
        Sumit Semwal <sumit.semwal@linaro.org>,
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        Shakeel Butt <shakeelb@google.com>,
        Jeroen de Borst <jeroendb@google.com>,
        Praveen Kaligineedi <pkaligineedi@google.com>,
        Stanislav Fomichev <sdf@google.com>
Subject: Re: [RFC PATCH v3 12/12] selftests: add ncdevmem, netcat for devmem
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My brain is slightly fried after trying to catch up on the thread 
for close to 2h. So forgive me if I'm missing something.
This applies to all emails I'm about to send :)

On Sun,  5 Nov 2023 18:44:11 -0800 Mina Almasry wrote:
> +	trigger_device_reset();

The user space must not be responsible for the reset.
We can add some temporary "recreate page pools" ndo
until the queue API is ready. 

But it should not be visible to the user in any way.

And then the kernel can issue the same reset when the netlink 
socket dies to flush device free lists.

Maybe we should also add a "allow device/all-queues reload" flag 
to the netlink API to differentiate drivers which can't implement 
full queue API later on. We want to make sure the defaults work well 
in our "target design", rather than at the first stage. And target
design will reload queues one by one.