On Mon, Jul 27, 2020 at 11:01 PM Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote: > > On 7/27/20 10:48 PM, Andrii Nakryiko wrote: > > On Mon, Jul 27, 2020 at 11:58 AM Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote: > >> > >> On 7/27/20 6:23 AM, Stephen Rothwell wrote: > >>> Hi all, > >>> > >>> Changes since 20200724: > >>> > >> > >> on i386: > >> when CONFIG_XPS is not set/enabled: > >> > >> ld: kernel/bpf/syscall.o: in function `__do_sys_bpf': > >> syscall.c:(.text+0x4482): undefined reference to `bpf_xdp_link_attach' > >> > > > > I can't repro this on x86-64 with CONFIG_XPS unset. Do you mind > > sharing the exact config you've used? > > No problem. I see this on i386 or x86_64. I am attaching the x86_64 > randconfig file instead of the i386 one. > > > I see that kernel/bpf/syscall.c doesn't include linux/netdevice.h > > directly, so something must be preventing netdevice.h to eventually > > get to bpf/syscall.c, but instead of guessing on the fix, I'd like to > > repro it first. Thanks! > > The build failure was causing me to see lots of builds failing, so I made > a simple patch so that I could get past this issue. My patch follows. > Feel free to fix it any way you like. > I was confused for a while by CONFIG_XPS, as nothing really depends on it. So it turned out the real dependency is CONFIG_NET, which is also unset in your random config. I just sent a fix, thanks for reporting and sharing the config! > Thanks. > --- > --- > kernel/bpf/syscall.c | 4 ++++ > 1 file changed, 4 insertions(+) > > --- mmotm-2020-0727-1818.orig/kernel/bpf/syscall.c > +++ mmotm-2020-0727-1818/kernel/bpf/syscall.c > @@ -3924,7 +3924,11 @@ static int link_create(union bpf_attr *a > ret = netns_bpf_link_create(attr, prog); > break; > case BPF_PROG_TYPE_XDP: > +#ifdef CONFIG_XPS > ret = bpf_xdp_link_attach(attr, prog); > +#else > + ret = -EINVAL; > +#endif > break; > default: > ret = -EINVAL; >
