On Tue, Mar 29, 2022 at 9:17 AM Mathieu Desnoyers
<mathieu.desnoyers@xxxxxxxxxxxx> wrote:
>
> >
> >> include/uapi/linux/user_events.h:
> >>
> >> struct user_bpf_iter {
> >>
> >> /* Offset of the data within the first iovec */
> >> __u32 iov_offset;
> >>
> >> /* Number of iovec structures */
> >> __u32 nr_segs;
> >>
> >> /* Pointer to iovec structures */
> >> const struct iovec *iov;
> >>
> >> ^ a pointer in a uapi header is usually a no-go. This should be a u64.
> >> };
> >>
> >> include/uapi/linux/user_events.h:
> >>
> >> struct user_bpf_context {
> >>
> >> /* Data type being passed (see union below) */
> >> __u32 data_type;
> >>
> >> /* Length of the data */
> >> __u32 data_len;
> >>
> >> /* Pointer to data, varies by data type */
> >> union {
> >> /* Kernel data (data_type == USER_BPF_DATA_KERNEL) */
> >> void *kdata;
> >>
> >> /* User data (data_type == USER_BPF_DATA_USER) */
> >> void *udata;
> >>
> >> /* Direct iovec (data_type == USER_BPF_DATA_ITER) */
> >> struct user_bpf_iter *iter;
> >>
> >> ^ likewise for the 3 pointers above. Should be u64 in uapi headers.
> >> };
> >> };
> >>
> >
> > The bpf structs are only used within a BPF program. At that point the pointer
> > sizes should all align, right?
>
> I must admit I do not know enough about the eBPF uapi practices to answer this.
> [CCing Alexei on this]
Mathieu,
Thanks for flagging.
Whoever added this user_bpf* stuff please remove it immediately.
It was never reviewed by bpf maintainers.
It's a hard Nack to add a bpf interface to user_events.
