On Thursday 03/07 at 22:09 +0000, Christophe Leroy wrote: > > > Le 06/03/2024 à 21:05, Calvin Owens a écrit : > > [Vous ne recevez pas souvent de courriers de jcalvinowens@xxxxxxxxx. Découvrez pourquoi ceci est important à https://aka.ms/LearnAboutSenderIdentification ] > > > > No BPF code has to change, except in struct_ops (for module refs). > > > > This conflicts with bpf-next because of this (relevant) series: > > > > https://lore.kernel.org/all/20240119225005.668602-1-thinker.li@xxxxxxxxx/ > > > > If something like this is merged down the road, it can go through > > bpf-next at leisure once the module_alloc change is in: it's a one-way > > dependency. > > > > Signed-off-by: Calvin Owens <jcalvinowens@xxxxxxxxx> > > --- > > kernel/bpf/Kconfig | 2 +- > > kernel/bpf/bpf_struct_ops.c | 28 ++++++++++++++++++++++++---- > > 2 files changed, 25 insertions(+), 5 deletions(-) > > > > diff --git a/kernel/bpf/Kconfig b/kernel/bpf/Kconfig > > index 6a906ff93006..77df483a8925 100644 > > --- a/kernel/bpf/Kconfig > > +++ b/kernel/bpf/Kconfig > > @@ -42,7 +42,7 @@ config BPF_JIT > > bool "Enable BPF Just In Time compiler" > > depends on BPF > > depends on HAVE_CBPF_JIT || HAVE_EBPF_JIT > > - depends on MODULES > > + select MODULE_ALLOC > > help > > BPF programs are normally handled by a BPF interpreter. This option > > allows the kernel to generate native code when a program is loaded > > diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c > > index 02068bd0e4d9..fbf08a1bb00c 100644 > > --- a/kernel/bpf/bpf_struct_ops.c > > +++ b/kernel/bpf/bpf_struct_ops.c > > @@ -108,11 +108,30 @@ const struct bpf_prog_ops bpf_struct_ops_prog_ops = { > > #endif > > }; > > > > +#if IS_ENABLED(CONFIG_MODULES) > > Can you avoid ifdefs as much as possible ? Similar to the other one, this was just a misguided attempt to avoid triggering -Wunused, I'll clean it up. This particular patch will look very different when rebased on bpf-next. > > static const struct btf_type *module_type; > > > > +static int bpf_struct_module_type_init(struct btf *btf) > > +{ > > + s32 module_id; > > Could be: > > if (!IS_ENABLED(CONFIG_MODULES)) > return 0; > > > + > > + module_id = btf_find_by_name_kind(btf, "module", BTF_KIND_STRUCT); > > + if (module_id < 0) > > + return 1; > > + > > + module_type = btf_type_by_id(btf, module_id); > > + return 0; > > +} > > +#else > > +static int bpf_struct_module_type_init(struct btf *btf) > > +{ > > + return 0; > > +} > > +#endif > > + > > void bpf_struct_ops_init(struct btf *btf, struct bpf_verifier_log *log) > > { > > - s32 type_id, value_id, module_id; > > + s32 type_id, value_id; > > const struct btf_member *member; > > struct bpf_struct_ops *st_ops; > > const struct btf_type *t; > > @@ -125,12 +144,10 @@ void bpf_struct_ops_init(struct btf *btf, struct bpf_verifier_log *log) > > #include "bpf_struct_ops_types.h" > > #undef BPF_STRUCT_OPS_TYPE > > > > - module_id = btf_find_by_name_kind(btf, "module", BTF_KIND_STRUCT); > > - if (module_id < 0) { > > + if (bpf_struct_module_type_init(btf)) { > > pr_warn("Cannot find struct module in btf_vmlinux\n"); > > return; > > } > > - module_type = btf_type_by_id(btf, module_id); > > > > for (i = 0; i < ARRAY_SIZE(bpf_struct_ops); i++) { > > st_ops = bpf_struct_ops[i]; > > @@ -433,12 +450,15 @@ static long bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, > > > > moff = __btf_member_bit_offset(t, member) / 8; > > ptype = btf_type_resolve_ptr(btf_vmlinux, member->type, NULL); > > + > > +#if IS_ENABLED(CONFIG_MODULES) > > Can't see anything depending on CONFIG_MODULES here, can you instead do: > > if (IS_ENABLED(CONFIG_MODULES) && ptype == module_type) { > > > if (ptype == module_type) { > > if (*(void **)(udata + moff)) > > goto reset_unlock; > > *(void **)(kdata + moff) = BPF_MODULE_OWNER; > > continue; > > } > > +#endif > > > > err = st_ops->init_member(t, member, kdata, udata); > > if (err < 0) > > -- > > 2.43.0 > > > >
