Ian Campbell
2013-Sep-04 08:36 UTC
Re: xen-netback: count number required slots for an skb more carefully
On Tue, 2013-09-03 at 23:04 -0700, Matt Wilson wrote:> On Wed, Sep 04, 2013 at 10:25:59AM +0800, annie li wrote: > > On 2013-9-4 5:53, Wei Liu wrote: > [...] > > >Matt, do you fancy sending the final version? IIRC the commit message > > >needs to be re-written. I personally still prefer Matt''s solution as > > >it a) make efficient use of the ring, b) uses ring pointers to > > >calculate slots which is most accurate, c) removes the dependence on > > >MAX_SKB_FRAGS in guest RX path. > > > > > >Anyway, we should get this fixed ASAP.Yes. Would there be any harm in just applying David''s patch (just because it is the one currently in our hands and it is based on a recent enough kernel). It looks right from a correctness PoV to me.> > Totally agree. This issue is easy to be reproduced with large MTU. > > It is better to upstream the fix soon in case others hit it and > > waste time to fix it. > > I''d like to go with Xi''s proposed patch that I posed earlier.I don''t think I saw that, do you have a message-id? ("Xi" is a bit too short for a search on my INBOX unfortunately).> The main > thing that''s kept me from sending a final version is lack of time to > retest against a newer kernel. > > Could someone help out with that? I probably can''t get to it until the > end of the week. > > Sorry for the delay. :-( > > --msw