From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <dada1@cosmosbay.com>
Subject: Re: [RFC,PATCH] loopback: calls netif_receive_skb() instead of netif_rx()
Date: Mon, 31 Mar 2008 08:38:22 +0200
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To: David Miller <davem@davemloft.net>
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David Miller a =E9crit :
> From: Eric Dumazet <dada1@cosmosbay.com>
> Date: Sat, 29 Mar 2008 09:18:03 +0100
>=20
>> BTW, can loopback_xmit() be called on an interrupt stack ?
>=20
> Absolutely, softirq processes TCP data, ACK goes out in
> softirq context.

yes, ICMP messages (if any are sent) too.

>=20
> Softirqs run on interrupt stacks just as hardirqs do.
>=20

Well, it depends.

Not on x86_32 with 8K stacks, and some other arches.
do_softirq() can use the underlying stack too.

Thank you