>> It looks like the first bad commit would be the following: >> >> [jenkins@zappa linux-stable-new]$ sudo bash bisect.sh -g >> 3ece782693c4b64d588dd217868558ab9a19bfe7 is the first bad commit >> commit 3ece782693c4b64d588dd217868558ab9a19bfe7 >> Author: Willem de Bruijn <willemb@xxxxxxxxxx> >> Date: Thu Aug 3 16:29:38 2017 -0400 >> >> sock: skb_copy_ubufs support for compound pages >> >> Refine skb_copy_ubufs to support compound pages. With upcoming TCP >> zerocopy sendmsg, such fragments may appear. >> >> The existing code replaces each page one for one. Splitting each >> compound page into an independent number of regular pages can result >> in exceeding limit MAX_SKB_FRAGS if data is not exactly page aligned. >> >> Instead, fill all destination pages but the last to PAGE_SIZE. >> Split the existing alloc + copy loop into separate stages: >> 1. compute bytelength and minimum number of pages to store this. >> 2. allocate >> 3. copy, filling each page except the last to PAGE_SIZE bytes >> 4. update skb frag array >> >> Signed-off-by: Willem de Bruijn <willemb@xxxxxxxxxx> >> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> >> >> :040000 040000 f1b652be7e59b1046400cad8e6be25028a88b8e2 >> 6ecf86d9f06a2d98946f531f1e4cf803de071b10 M include >> :040000 040000 8420cf451fcf51f669ce81437ce7e0aacc33d2eb >> 4fc8384362693e4619fab39b0a945f6f2349226b M net >> >> Here is the bisect log: > > > Thanks for the hard bisecting. > > Cc netdev and Willem. This is being discussed in http://lkml.kernel.org/r/<CAF=yD-LWyCD4Y0aJ9O0e_CHLR+3JOeKicRRTEVCPxgw4XOcqGQ@xxxxxxxxxxxxxx> David also previously reported this at https://bugzilla.kernel.org/show_bug.cgi?id=197861 which has a pointer to the above thread, too. Let's discuss this in a single thread. I have suggested a fix there. Thanks for bisecting. Please also test the patch in the above thread if possible.
