On Mon, Sep 5, 2022 at 12:34 PM Toke Høiland-Jørgensen <toke@xxxxxxxxxx> wrote: > > From: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx> > > BPF ABI always uses 64-bit return value, but so far __bpf_prog_run and > higher level wrappers always truncated the return value to 32-bit. We want > to be able to introduce a new BPF program type that returns a PTR_TO_BTF_ID > or NULL from the BPF program to the caller context in the kernel. To be > able to use this returned pointer value, the bpf_prog_run invocation needs > to be able to return a 64-bit value, so update the definitions to allow > this. > > To avoid code churn in the whole kernel, we let the compiler handle > truncation normally, and allow new call sites to utilize the 64-bit > return value, by receiving the return value as a u64. > > Reviewed-by: Stanislav Fomichev <sdf@xxxxxxxxxx> > Signed-off-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx> > Signed-off-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx> Acked-by: Song Liu <song@xxxxxxxxxx>
