BPF_F_KPROBE_MULTI_RETURN was deleted on golang.org/x/sys v0.14.0

[keisku]

I am asking this question out of personal curiosity. There are no negative effects occurring at the moment.

golang/sys@1168e25 deleted BPF_F_KPROBE_MULTI_RETURN in golang/sys/unix/zerrors_linux.go to fix golang/go#63833

Therefore, https://github.com/cilium/ebpf/blob/v0.12.2/internal/unix/types_linux.go#L41 causes ../../../go/pkg/mod/github.com/cilium/ebpf@v0.12.2/internal/unix/types_linux.go:41:36: undefined: linux.BPF_F_KPROBE_MULTI_RETURN when using bpf2go if we update golang.org/x/sys v0.6.0 to v0.14.0.

Of course, we can use bpf2go without any problems if I switch to golang.org/x/sys v0.6.0 in go.mod.

I am wondering if there is any negative impacts when I use Linux v6.6+ and cilium/ebpf.
FYI, we can still see BPF_F_KPROBE_MULTI_RETURN in https://github.com/torvalds/linux/blob/v6.6/include/uapi/linux/bpf.h#L1188-L1193

[mythi]

golang/sys@1168e25 deleted BPF_F_KPROBE_MULTI_RETURN in golang/sys/unix/zerrors_linux.go to fix golang/go#63833

This will trigger errors where both cilium/ebpf and golang.org/x/sys v0.14.0 are used, AFAICS. I'm already seeing dependabot updates that trigger

 # github.com/cilium/ebpf/internal/unix
Error: vendor/github.com/cilium/ebpf/internal/unix/types_linux.go:41:36: undefined: unix.BPF_F_KPROBE_MULTI_RETURN

I wonder if the removal happened by accident?

[brycekahle]

It must be a side-effect of this change torvalds/linux@c5487f8 which changes from a #define to an enum.

[brycekahle]

I filed an issue golang/go#63969

[ti-mo]

Please upgrade to v0.12.3 to work around this issue.