On Thu, 24 Dec 2009 14:18:12 -0500
Michael Breuer [off-list ref] wrote:

I'll be the first to admit I don't know much about network drivers... 
but I am wondering why __free_page(frag->page); is called in 
skb_put_frags when the fragment length is zero. I don't see why that 
page pointer wouldn't potentially be reused afterwords.

When using Jumbo frames, the sky2 driver allocates pages to hold
the larger part of the frame. With 9K MTU it will allocate 2 * 4K pages
and then 1K for start of frame. Then if frame is <= 1K it will drop
the extra pages.  Not sure why this broke now, I am not a VM expert.

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