Dmitry Safonov <dima@xxxxxxxxxx> wrote: > So, here I add a compatible layer to xfrm. > As xfrm uses netlink notifications, kernel should send them in ABI > format that an application will parse. The proposed solution is > to save the ABI of bind() syscall. The realization detail is > to create kernel-hidden, non visible to userspace netlink groups > for compat applications. Why not use exisiting netlink support? Just add the 32bit skb to skb64->frag_list and let netlink find if tasks needs 64 or 32 one. It only needs this small fix to properly signal the end of a dump: https://marc.info/?l=linux-netdev&m=126625240303351&w=2 I had started a second attempt to make xfrm compat work, but its still in early stage. One link that might still have some value: https://git.breakpoint.cc/cgit/fw/net-next.git/commit/?h=xfrm_config_compat_07&id=f64430e6d9e297f3990f485a4832e273751b9869 (compat structure definitions with BUILD_BUG_ON checking) My plan was to make xfrm compat work strictly as shrinker (64->32) and expander (32->64), i.e. no/little changes to exisiting code and pass all "expanded" skbs through existing xfrm rcv functions. Example to illustrate idea: https://git.breakpoint.cc/cgit/fw/net-next.git/commit/?h=xfrm_config_compat_07&id=c622f067849b02170127b69471cb3481e4bc9e49 ... its supposed to take 64bit skb and create a 32bit one from it. Just for reference; I currently don't plan to work on this again. -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
