From: Tiezhu Yang Use BPF_TRAMP_F_INDIRECT flag to detect struct ops and emit proper prologue and epilogue for this case. With this patch, all of the struct_ops related testcases (except struct_ops_multi_pages) passed on LoongArch. The testcase struct_ops_multi_pages failed is because the actual image_pages_cnt is 40 which is bigger than MAX_TRAMP_IMAGE_PAGES. Before: $ sudo ./test_progs -t struct_ops -d struct_ops_multi_pages ... WATCHDOG: test case struct_ops_module/struct_ops_load executes for 10 seconds... After: $ sudo ./test_progs -t struct_ops -d struct_ops_multi_pages ... #15 bad_struct_ops:OK ... #399 struct_ops_autocreate:OK ... #400 struct_ops_kptr_return:OK ... #401 struct_ops_maybe_null:OK ... #402 struct_ops_module:OK ... #404 struct_ops_no_cfi:OK ... #405 struct_ops_private_stack:SKIP ... #406 struct_ops_refcounted:OK Summary: 8/25 PASSED, 3 SKIPPED, 0 FAILED Signed-off-by: Tiezhu Yang --- arch/loongarch/net/bpf_jit.c | 71 ++++++++++++++++++++++++------------ 1 file changed, 47 insertions(+), 24 deletions(-) diff --git a/arch/loongarch/net/bpf_jit.c b/arch/loongarch/net/bpf_jit.c index ac5ce3a28..6a84fb104 100644 --- a/arch/loongarch/net/bpf_jit.c +++ b/arch/loongarch/net/bpf_jit.c @@ -1603,6 +1603,7 @@ static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_i struct bpf_tramp_links *fentry = &tlinks[BPF_TRAMP_FENTRY]; struct bpf_tramp_links *fexit = &tlinks[BPF_TRAMP_FEXIT]; struct bpf_tramp_links *fmod_ret = &tlinks[BPF_TRAMP_MODIFY_RETURN]; + bool is_struct_ops = flags & BPF_TRAMP_F_INDIRECT; int ret, save_ret; void *orig_call = func_addr; u32 **branches = NULL; @@ -1678,18 +1679,31 @@ static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_i stack_size = round_up(stack_size, 16); - /* For the trampoline called from function entry */ - /* RA and FP for parent function*/ - emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, -16); - emit_insn(ctx, std, LOONGARCH_GPR_RA, LOONGARCH_GPR_SP, 8); - emit_insn(ctx, std, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, 0); - emit_insn(ctx, addid, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, 16); - - /* RA and FP for traced function*/ - emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, -stack_size); - emit_insn(ctx, std, LOONGARCH_GPR_T0, LOONGARCH_GPR_SP, stack_size - 8); - emit_insn(ctx, std, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_size - 16); - emit_insn(ctx, addid, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_size); + if (!is_struct_ops) { + /* + * For the trampoline called from function entry, + * the frame of traced function and the frame of + * trampoline need to be considered. + */ + emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, -16); + emit_insn(ctx, std, LOONGARCH_GPR_RA, LOONGARCH_GPR_SP, 8); + emit_insn(ctx, std, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, 0); + emit_insn(ctx, addid, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, 16); + + emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, -stack_size); + emit_insn(ctx, std, LOONGARCH_GPR_T0, LOONGARCH_GPR_SP, stack_size - 8); + emit_insn(ctx, std, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_size - 16); + emit_insn(ctx, addid, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_size); + } else { + /* + * For the trampoline called directly, just handle + * the frame of trampoline. + */ + emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, -stack_size); + emit_insn(ctx, std, LOONGARCH_GPR_RA, LOONGARCH_GPR_SP, stack_size - 8); + emit_insn(ctx, std, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_size - 16); + emit_insn(ctx, addid, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_size); + } /* callee saved register S1 to pass start time */ emit_insn(ctx, std, LOONGARCH_GPR_S1, LOONGARCH_GPR_FP, -sreg_off); @@ -1779,21 +1793,30 @@ static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_i emit_insn(ctx, ldd, LOONGARCH_GPR_S1, LOONGARCH_GPR_FP, -sreg_off); - /* trampoline called from function entry */ - emit_insn(ctx, ldd, LOONGARCH_GPR_T0, LOONGARCH_GPR_SP, stack_size - 8); - emit_insn(ctx, ldd, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_size - 16); - emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, stack_size); + if (!is_struct_ops) { + /* trampoline called from function entry */ + emit_insn(ctx, ldd, LOONGARCH_GPR_T0, LOONGARCH_GPR_SP, stack_size - 8); + emit_insn(ctx, ldd, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_size - 16); + emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, stack_size); + + emit_insn(ctx, ldd, LOONGARCH_GPR_RA, LOONGARCH_GPR_SP, 8); + emit_insn(ctx, ldd, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, 0); + emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, 16); - emit_insn(ctx, ldd, LOONGARCH_GPR_RA, LOONGARCH_GPR_SP, 8); - emit_insn(ctx, ldd, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, 0); - emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, 16); + if (flags & BPF_TRAMP_F_SKIP_FRAME) + /* return to parent function */ + emit_insn(ctx, jirl, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_RA, 0); + else + /* return to traced function */ + emit_insn(ctx, jirl, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_T0, 0); + } else { + /* trampoline called directly */ + emit_insn(ctx, ldd, LOONGARCH_GPR_RA, LOONGARCH_GPR_SP, stack_size - 8); + emit_insn(ctx, ldd, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_size - 16); + emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, stack_size); - if (flags & BPF_TRAMP_F_SKIP_FRAME) - /* return to parent function */ emit_insn(ctx, jirl, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_RA, 0); - else - /* return to traced function */ - emit_insn(ctx, jirl, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_T0, 0); + } ret = ctx->idx; out: -- 2.25.1