diff options
| author | Menglong Dong <menglong8.dong@gmail.com> | 2025-11-18 20:36:32 +0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2025-11-24 09:47:03 -0800 |
| commit | 373f2f44c300815c5f170e89560ac361c0053dfe (patch) | |
| tree | 3dad2f2bbdf4514eb78fcdafc781e03a2674183b /include/linux | |
| parent | 47c9214dcbea9043ac20441a285c7bb5486b8b2d (diff) | |
bpf,x86: adjust the "jmp" mode for bpf trampoline
In the origin call case, if BPF_TRAMP_F_SKIP_FRAME is not set, it means
that the trampoline is not called, but "jmp".
Introduce the function bpf_trampoline_use_jmp() to check if the trampoline
is in "jmp" mode.
Do some adjustment on the "jmp" mode for the x86_64. The main adjustment
that we make is for the stack parameter passing case, as the stack
alignment logic changes in the "jmp" mode without the "rip". What's more,
the location of the parameters on the stack also changes.
Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Link: https://lore.kernel.org/r/20251118123639.688444-5-dongml2@chinatelecom.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/bpf.h | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 30fb40421405..2f79afe81482 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1264,6 +1264,18 @@ typedef void (*bpf_trampoline_exit_t)(struct bpf_prog *prog, u64 start, bpf_trampoline_enter_t bpf_trampoline_enter(const struct bpf_prog *prog); bpf_trampoline_exit_t bpf_trampoline_exit(const struct bpf_prog *prog); +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_JMP +static inline bool bpf_trampoline_use_jmp(u64 flags) +{ + return flags & BPF_TRAMP_F_CALL_ORIG && !(flags & BPF_TRAMP_F_SKIP_FRAME); +} +#else +static inline bool bpf_trampoline_use_jmp(u64 flags) +{ + return false; +} +#endif + struct bpf_ksym { unsigned long start; unsigned long end; |