netdev - Question on comment in dev_queue_xmit

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Message-ID: <40bf4696-2c58-f5ba-e81f-46a2a5e7887a@candelatech.com>
Date:   Tue, 8 Feb 2022 15:51:17 -0800
From:   Ben Greear <greearb@...delatech.com>
To:     Salam Noureddine <noureddine@...sta.com>
Cc:     netdev <netdev@...r.kernel.org>
Subject: Question on comment in dev_queue_xmit_nit

Hello Salam,

After an 8 day torture test on a hacked 5.15.7+ kernel doing wifi testing, our system crashed
in the dev_queue_xmit_nit method, evidently 'skb' is NULL.

gdb claims it is the 'skb2 = skb_clone ...' line below.  Now, this crash could
be fault of my local patches or other random things, but the comment caught
my attention.  It is cloning once per loop as far as I can see, so why the comment
about 'done only once' ?

		/* need to clone skb, done only once */
		skb2 = skb_clone(skb, GFP_ATOMIC);
		if (!skb2)
			goto out_unlock;

Thanks,
Ben

-- 
Ben Greear <greearb@...delatech.com>
Candela Technologies Inc  http://www.candelatech.com