On Wed, 2021-02-17 at 23:16 -0800, Yonghong Song wrote:
> On 2/15/21 5:12 PM, Ilya Leoshkevich wrote:
> > The logic follows that of BTF_KIND_INT most of the time.
> > Sanitization
> > replaces BTF_KIND_FLOATs with equally-sized BTF_KIND_INTs on older
> > kernels.
> >
> > Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx>
> > ---
> > tools/lib/bpf/btf.c | 44
> > +++++++++++++++++++++++++++++++++
> > tools/lib/bpf/btf.h | 8 ++++++
> > tools/lib/bpf/btf_dump.c | 4 +++
> > tools/lib/bpf/libbpf.c | 29 +++++++++++++++++++++-
> > tools/lib/bpf/libbpf.map | 5 ++++
> > tools/lib/bpf/libbpf_internal.h | 2 ++
> > 6 files changed, 91 insertions(+), 1 deletion(-)
> >
> > diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
> > index d9c10830d749..07a30e98c3de 100644
> > --- a/tools/lib/bpf/btf.c
> > +++ b/tools/lib/bpf/btf.c
[...]
> > @@ -2445,6 +2450,9 @@ static void bpf_object__sanitize_btf(struct
> > bpf_object *obj, struct btf *btf)
> > } else if (!has_func_global && btf_is_func(t)) {
> > /* replace BTF_FUNC_GLOBAL with
> > BTF_FUNC_STATIC */
> > t->info = BTF_INFO_ENC(BTF_KIND_FUNC, 0,
> > 0);
> > + } else if (!has_float && btf_is_float(t)) {
> > + /* replace FLOAT with INT */
> > + t->info = BTF_INFO_ENC(BTF_KIND_FLOAT, 0,
> > 0);
>
> You can replace float with a "pointer to void" type.
Wouldn't this cause problems with 32-bit floats on 64-bit machines?
[...]
