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Subject: Re: Memory providers multiplexing (Was: [PATCH net-next v4 4/5]
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To:     Eric Dumazet <edumazet@google.com>
Cc:     Mina Almasry <almasrymina@google.com>,
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From:   David Ahern <dsahern@kernel.org>
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On 7/3/23 11:15 AM, Eric Dumazet wrote:
> On Mon, Jul 3, 2023 at 4:45 PM David Ahern <dsahern@kernel.org> wrote:
> 
>> That is my expectation. The tcpdump is just an easy example of accessing
>> the skb page frags. skb_copy_and_csum_bits used by icmp is another
>> example that can walk frags wanting access to device memory. You did not
>> cause a panic or trip a WARN_ON for example with the tcpdump?
>>
> 
> ICMP packets do not land on the queues having devmem buffers, for
> obvious reasons.

I was not referring to ICMP packets coming in to the nic, but rather an
icmp getting triggered during stack processing.

> 
> Only chosen TCP flows are steered to these queues.

of course.