Re: [bug, netconsole, SLUB] BUG skbuff_head_cache: Poisonoverwritten

[David Miller]

From: "Vegard Nossum" <vegard.nossum@xxxxxxxxx>
Date: Fri, 18 Jul 2008 09:03:50 +0200

> > It's supposed to be 0x6b, this would be a "--"
> 
> You're right! Oops. In my defence, I wrote that at 2 AM last night ;-)
> 
> > Also it (more likely IMHO) could be clearing a flag with the value 0x01.
> 
> It could be. But like I said in a later e-mail, the thing is likely
> sk_buff->truesize. Which is not a flags variable. It _is_ however, a
> counter, which is frequently -= and atomic_sub()ed.

skb->truesize is ever incremented or decremented by only one.

Usually it is changed by the entire packet size, or at least one MSS's
worth.

On packet free, it will be decremented by at least sizeof(struct sk_buff)
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/