diff options
| author | Leon Hwang <leon.hwang@linux.dev> | 2025-09-19 12:41:09 +0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2025-09-23 12:07:46 -0700 |
| commit | ccb4f5d91ec43c05ba165ccfc7ed889eb9cdfd05 (patch) | |
| tree | 0c7b1d0fb83f232083059b08732b027d6aa49205 /kernel/bpf/btf.c | |
| parent | 2383e45f1da7ac73683ac3494a205bc878a58cc9 (diff) | |
bpf: Allow union argument in trampoline based programs
Currently, functions with 'union' arguments cannot be traced with
fentry/fexit:
bpftrace -e 'fentry:release_pages { exit(); }' -v
The function release_pages arg0 type UNION is unsupported.
The type of the 'release_pages' arg0 is defined as:
typedef union {
struct page **pages;
struct folio **folios;
struct encoded_page **encoded_pages;
} release_pages_arg __attribute__ ((__transparent_union__));
This patch relaxes the restriction by allowing function arguments of type
'union' to be traced in verifier.
Reviewed-by: Amery Hung <ameryhung@gmail.com>
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Link: https://lore.kernel.org/r/20250919044110.23729-2-leon.hwang@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel/bpf/btf.c')
| -rw-r--r-- | kernel/bpf/btf.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 9f47a3aa7ff8..0de8fc8a0e0b 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -6751,7 +6751,7 @@ bool btf_ctx_access(int off, int size, enum bpf_access_type type, /* skip modifiers */ while (btf_type_is_modifier(t)) t = btf_type_by_id(btf, t->type); - if (btf_type_is_small_int(t) || btf_is_any_enum(t) || __btf_type_is_struct(t)) + if (btf_type_is_small_int(t) || btf_is_any_enum(t) || btf_type_is_struct(t)) /* accessing a scalar */ return true; if (!btf_type_is_ptr(t)) { @@ -7323,7 +7323,7 @@ static int __get_type_size(struct btf *btf, u32 btf_id, if (btf_type_is_ptr(t)) /* kernel size of pointer. Not BPF's size of pointer*/ return sizeof(void *); - if (btf_type_is_int(t) || btf_is_any_enum(t) || __btf_type_is_struct(t)) + if (btf_type_is_int(t) || btf_is_any_enum(t) || btf_type_is_struct(t)) return t->size; return -EINVAL; } @@ -7332,7 +7332,7 @@ static u8 __get_type_fmodel_flags(const struct btf_type *t) { u8 flags = 0; - if (__btf_type_is_struct(t)) + if (btf_type_is_struct(t)) flags |= BTF_FMODEL_STRUCT_ARG; if (btf_type_is_signed_int(t)) flags |= BTF_FMODEL_SIGNED_ARG; @@ -7373,7 +7373,7 @@ int btf_distill_func_proto(struct bpf_verifier_log *log, return -EINVAL; } ret = __get_type_size(btf, func->type, &t); - if (ret < 0 || __btf_type_is_struct(t)) { + if (ret < 0 || btf_type_is_struct(t)) { bpf_log(log, "The function %s return type %s is unsupported.\n", tname, btf_type_str(t)); |