diff options
| author | Kumar Kartikeya Dwivedi <memxor@gmail.com> | 2026-08-08 02:39:21 +0200 |
|---|---|---|
| committer | Eduard Zingerman <eddyz87@gmail.com> | 2026-08-08 03:03:25 -0700 |
| commit | 04962afb3cd6a3cbf1a3679c0c95049833db36c1 (patch) | |
| tree | 61d6aea714ec23818114aa20b57dddb5ec2480ac /kernel | |
| parent | 8b365b3c68b474a1053ec0755dacdc751578afb0 (diff) | |
bpf: Rename 'early' BTF checking as a preparation phase
BTF processing is split around subprogram discovery. The first phase gets
program BTF and imports func_info because a BTF-tagged exception callback
may not be referenced by any instruction. Subprogram discovery needs this
metadata to find it.
The later phase validates func_info and line_info against the complete
subprogram table and applies CO-RE relocations. This split breaks a real
dependency cycle rather than merely running the same checks early.
Rename bpf_check_btf_info_early() and check_btf_func_early() to preparation
names that reflect this role. Add short call-site comments to make the two
phases and their responsibilities clear.
No functional change is intended.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Reviewed-by: Amery Hung <ameryhung@gmail.com>
Link: https://patch.msgid.link/20260808003938.3486067-2-memxor@gmail.com
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/check_btf.c | 14 | ||||
| -rw-r--r-- | kernel/bpf/verifier.c | 4 |
2 files changed, 10 insertions, 8 deletions
diff --git a/kernel/bpf/check_btf.c b/kernel/bpf/check_btf.c index 93bebe6fe12e..0e8b3ccc7a5b 100644 --- a/kernel/bpf/check_btf.c +++ b/kernel/bpf/check_btf.c @@ -28,9 +28,9 @@ static int check_abnormal_return(struct bpf_verifier_env *env) #define MIN_BPF_FUNCINFO_SIZE 8 #define MAX_FUNCINFO_REC_SIZE 252 -static int check_btf_func_early(struct bpf_verifier_env *env, - const union bpf_attr *attr, - bpfptr_t uattr) +static int prepare_btf_func(struct bpf_verifier_env *env, + const union bpf_attr *attr, + bpfptr_t uattr) { u32 krec_size = sizeof(struct bpf_func_info); const struct btf_type *type, *func_proto; @@ -407,9 +407,9 @@ static int check_core_relo(struct bpf_verifier_env *env, return err; } -int bpf_check_btf_info_early(struct bpf_verifier_env *env, - const union bpf_attr *attr, - bpfptr_t uattr) +int bpf_prepare_btf_info(struct bpf_verifier_env *env, + const union bpf_attr *attr, + bpfptr_t uattr) { struct btf *btf; int err; @@ -429,7 +429,7 @@ int bpf_check_btf_info_early(struct bpf_verifier_env *env, } env->prog->aux->btf = btf; - err = check_btf_func_early(env, attr, uattr); + err = prepare_btf_func(env, attr, uattr); if (err) return err; return 0; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 9eabc5123e5a..ce755c8b0ee2 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -20135,7 +20135,8 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr, INIT_LIST_HEAD(&env->explored_states[i]); INIT_LIST_HEAD(&env->free_list); - ret = bpf_check_btf_info_early(env, attr, uattr); + /* Prepare BTF and func_info needed to discover all subprograms. */ + ret = bpf_prepare_btf_info(env, attr, uattr); if (ret < 0) goto skip_full_check; @@ -20147,6 +20148,7 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr, if (ret < 0) goto skip_full_check; + /* Validate BTF against the complete subprogram layout and apply CO-RE. */ ret = bpf_check_btf_info(env, attr, uattr); if (ret < 0) goto skip_full_check; |