It looks like the Intel out-of-tree driver is carrying around some legacy HAVE_PAGE_COUNT_BULK_UPDATE option that is making their porting efforts difficult. Th

It looks like the Intel out-of-tree driver is carrying around some legacy HAVE_PAGE_COUNT_BULK_UPDATE option that is making their porting efforts difficult. This commit in upstream ends up getting split in half: https://github.com/torvalds/linux/commit/8ce29c679a6ecefb88dc794260f4e91a284eed9a https://github.com/torvalds/linux/commit/8ce29c679a6ecefb88d... With only 3 lines of it getting pulled into i40e-2.13.10: https://github.com/dmarion/i40e/blob/master/src/i40e_txrx.c#L1836 https://github.com/dmarion/i40e/blob/master/src/i40e_txrx.c#... https://github.com/dmarion/i40e/blob/master/src/i40e_txrx.c#L2355 https://github.com/dmarion/i40e/blob/master/src/i40e_txrx.c#... (Can't link git diff line for 2.13.10->2.14.13 because diff is too big, annoying!) And the final line getting pulled into i40e-2.14.13: https://github.com/dmarion/i40e/commit/135d6d885aa4704180e10e6d157405e3e65165d9#diff-9c8458f2e0e8996a46dc78440383f0ed85e512826231730d79fcfdca318fd065R2354 https://github.com/dmarion/i40e/commit/135d6d885aa4704180e10... --- if (unlikely(!pagecnt_bias)) { +++ if (unlikely(pagecnt_bias == 1)) { Best thing I can find in i40e_txrx.c where a single patch in Linux upstream got split across 2.13.10 and 2.14.13. Not a smoking gun exactly, still some exercise left for the reader.