Hi Dave, On Tue, 29 Nov 2016 20:07:08 +1100 Stephen Rothwell <s...@canb.auug.org.au> wrote: > > Hi Jeff, > > On Tue, 29 Nov 2016 10:43:04 +1100 Stephen Rothwell <s...@canb.auug.org.au> > wrote: > > > > On Mon, 28 Nov 2016 14:26:02 -0800 Jeff Kirsher > > <jeffrey.t.kirs...@intel.com> wrote: > > > > > > On Mon, 2016-11-28 at 10:42 -0500, Alexander Duyck wrote: > > > > When I implemented the GSO partial support in the Intel drivers I was > > > > using > > > > lco_csum to compute the checksum that we needed to plug into the IPv4 > > > > checksum field in order to cancel out the data that was not a part of > > > > the > > > > IPv4 header. However this didn't take into account that the transport > > > > offset might be pointing to the inner transport header. > > > > > > > > Instead of using lco_csum I have just coded around it so that we can use > > > > the outer IP header plus the IP header length to determine where we need > > > > to > > > > start our checksum and then just call csum_partial ourselves. > > > > > > > > This should fix the SIT issue reported on igb interfaces as well as > > > > simliar > > > > issues that would pop up on other Intel NICs. > > > > > > > > --- > > > > > > > > Alexander Duyck (2): > > > > igb/igbvf: Don't use lco_csum to compute IPv4 checksum > > > > ixgbe/ixgbevf: Don't use lco_csum to compute IPv4 checksum > > > > > > Stephen, I have applied Alex's patches to my net-queue tree. Can you > > > confirm they resolve the bug seen? > > > > Its a bit tricky because the origin problem only happens on my > > production server (ozlabs.org), but I will see if I can manage to just > > remove and reload the driver ... though, the server is running a 4.7.8 > > kernel and I am wondering how well these patches will apply? > > We have a winner! This fixes my problem, so I can run at full speed > with gso and tso enabled in the sit interface and tx-gso-partial > enabled on the underlying ethernet. > > Thanks to everyone for diagnosis and solution. > > It would be nice if this fix went into the stable kernels as well so it > will turn up in the distro kernels eventually.
It looks like these 2 commits: 516165a1e2f2 igb/igbvf: Don't use lco_csum to compute IPv4 checksum c54cdc316dbd ixgbe/ixgbevf: Don't use lco_csum to compute IPv4 checksum have not been sent to stable. They fix a bug introduced in v4.7-rc1 and so need to go into 4.7 and 4.8 stable trees. -- Cheers, Stephen Rothwell
