Merge branch 'bpf-x86-allow-function-arguments-up-to-12-for-tracing'

Menglong Dong says:

====================
bpf, x86: allow function arguments up to 12 for TRACING

From: Menglong Dong <imagedong@tencent.com>

For now, the BPF program of type BPF_PROG_TYPE_TRACING can only be used
on the kernel functions whose arguments count less than or equal to 6, if
not considering '> 8 bytes' struct argument. This is not friendly at all,
as too many functions have arguments count more than 6. According to the
current kernel version, below is a statistics of the function arguments
count:

argument count | function count
7              | 704
8              | 270
9              | 84
10             | 47
11             | 47
12             | 27
13             | 22
14             | 5
15             | 0
16             | 1

Therefore, let's enhance it by increasing the function arguments count
allowed in arch_prepare_bpf_trampoline(), for now, only x86_64.

In the 1st patch, we save/restore regs with BPF_DW size to make the code
in save_regs()/restore_regs() simpler.

In the 2nd patch, we make arch_prepare_bpf_trampoline() support to copy
function arguments in stack for x86 arch. Therefore, the maximum
arguments can be up to MAX_BPF_FUNC_ARGS for FENTRY, FEXIT and
MODIFY_RETURN. Meanwhile, we clean the potential garbage value when we
copy the arguments on-stack.

And the 3rd patch is for the testcases of the this series.

Changes since v9:
- fix the failed test cases of trampoline_count and get_func_args_test
  in the 3rd patch

Changes since v8:
- change the way to test fmod_ret in the 3rd patch

Changes since v7:
- split the testcases, and add fentry_many_args/fexit_many_args to
  DENYLIST.aarch64 in 3rd patch

Changes since v6:
- somit nits from commit message and comment in the 1st patch
- remove the inline in get_nr_regs() in the 1st patch
- rename some function and various in the 1st patch

Changes since v5:
- adjust the commit log of the 1st patch, avoiding confusing people that
  bugs exist in current code
- introduce get_nr_regs() to get the space that used to pass args on
  stack correct in the 2nd patch
- add testcases to tracing_struct.c instead of fentry_test.c and
  fexit_test.c

Changes since v4:
- consider the case of the struct in arguments can't be hold by regs
- add comment for some code
- add testcases for MODIFY_RETURN
- rebase to the latest

Changes since v3:
- try make the stack pointer 16-byte aligned. Not sure if I'm right :)
- introduce clean_garbage() to clean the grabage when argument count is 7
- use different data type in bpf_testmod_fentry_test{7,12}
- add testcase for grabage values in ctx

Changes since v2:
- keep MAX_BPF_FUNC_ARGS still
- clean garbage value in upper bytes in the 2nd patch
- move bpf_fentry_test{7,12} to bpf_testmod.c and rename them to
  bpf_testmod_fentry_test{7,12} meanwhile in the 3rd patch

Changes since v1:
- change the maximun function arguments to 14 from 12
- add testcases (Jiri Olsa)
- instead EMIT4 with EMIT3_off32 for "lea" to prevent overflow
====================

Link: https://lore.kernel.org/r/20230713040738.1789742-1-imagedong@tencent.comSigned-off-by: Alexei Starovoitov <ast@kernel.org>

arch/x86/net/bpf_jit_comp.c

@@ -1857,59 +1857,177 @@ st:			if (is_imm8(insn->off))
 	return proglen;
 }
 
-static void save_regs(const struct btf_func_model *m, u8 **prog, int nr_regs,
-		      int stack_size)
+static void clean_stack_garbage(const struct btf_func_model *m,
+				u8 **pprog, int nr_stack_slots,
+				int stack_size)
 {
-	int i, j, arg_size;
-	bool next_same_struct = false;
+	int arg_size, off;
+	u8 *prog;
+
+	/* Generally speaking, the compiler will pass the arguments
+	 * on-stack with "push" instruction, which will take 8-byte
+	 * on the stack. In this case, there won't be garbage values
+	 * while we copy the arguments from origin stack frame to current
+	 * in BPF_DW.
+	 *
+	 * However, sometimes the compiler will only allocate 4-byte on
+	 * the stack for the arguments. For now, this case will only
+	 * happen if there is only one argument on-stack and its size
+	 * not more than 4 byte. In this case, there will be garbage
+	 * values on the upper 4-byte where we store the argument on
+	 * current stack frame.
+	 *
+	 * arguments on origin stack:
+	 *
+	 * stack_arg_1(4-byte) xxx(4-byte)
+	 *
+	 * what we copy:
+	 *
+	 * stack_arg_1(8-byte): stack_arg_1(origin) xxx
+	 *
+	 * and the xxx is the garbage values which we should clean here.
+	 */
+	if (nr_stack_slots != 1)
+		return;
+
+	/* the size of the last argument */
+	arg_size = m->arg_size[m->nr_args - 1];
+	if (arg_size <= 4) {
+		off = -(stack_size - 4);
+		prog = *pprog;
+		/* mov DWORD PTR [rbp + off], 0 */
+		if (!is_imm8(off))
+			EMIT2_off32(0xC7, 0x85, off);
+		else
+			EMIT3(0xC7, 0x45, off);
+		EMIT(0, 4);
+		*pprog = prog;
+	}
+}
+
+/* get the count of the regs that are used to pass arguments */
+static int get_nr_used_regs(const struct btf_func_model *m)
+{
+	int i, arg_regs, nr_used_regs = 0;
+
+	for (i = 0; i < min_t(int, m->nr_args, MAX_BPF_FUNC_ARGS); i++) {
+		arg_regs = (m->arg_size[i] + 7) / 8;
+		if (nr_used_regs + arg_regs <= 6)
+			nr_used_regs += arg_regs;
+
+		if (nr_used_regs >= 6)
+			break;
+	}
+
+	return nr_used_regs;
+}
+
+static void save_args(const struct btf_func_model *m, u8 **prog,
+		      int stack_size, bool for_call_origin)
+{
+	int arg_regs, first_off, nr_regs = 0, nr_stack_slots = 0;
+	int i, j;
 
 	/* Store function arguments to stack.
 	 * For a function that accepts two pointers the sequence will be:
 	 * mov QWORD PTR [rbp-0x10],rdi
 	 * mov QWORD PTR [rbp-0x8],rsi
 	 */
-	for (i = 0, j = 0; i < min(nr_regs, 6); i++) {
-		/* The arg_size is at most 16 bytes, enforced by the verifier. */
-		arg_size = m->arg_size[j];
-		if (arg_size > 8) {
-			arg_size = 8;
-			next_same_struct = !next_same_struct;
-		}
+	for (i = 0; i < min_t(int, m->nr_args, MAX_BPF_FUNC_ARGS); i++) {
+		arg_regs = (m->arg_size[i] + 7) / 8;
 
-		emit_stx(prog, bytes_to_bpf_size(arg_size),
-			 BPF_REG_FP,
-			 i == 5 ? X86_REG_R9 : BPF_REG_1 + i,
-			 -(stack_size - i * 8));
+		/* According to the research of Yonghong, struct members
+		 * should be all in register or all on the stack.
+		 * Meanwhile, the compiler will pass the argument on regs
+		 * if the remaining regs can hold the argument.
+		 *
+		 * Disorder of the args can happen. For example:
+		 *
+		 * struct foo_struct {
+		 *     long a;
+		 *     int b;
+		 * };
+		 * int foo(char, char, char, char, char, struct foo_struct,
+		 *         char);
+		 *
+		 * the arg1-5,arg7 will be passed by regs, and arg6 will
+		 * by stack.
+		 */
+		if (nr_regs + arg_regs > 6) {
+			/* copy function arguments from origin stack frame
+			 * into current stack frame.
+			 *
+			 * The starting address of the arguments on-stack
+			 * is:
+			 *   rbp + 8(push rbp) +
+			 *   8(return addr of origin call) +
+			 *   8(return addr of the caller)
+			 * which means: rbp + 24
+			 */
+			for (j = 0; j < arg_regs; j++) {
+				emit_ldx(prog, BPF_DW, BPF_REG_0, BPF_REG_FP,
+					 nr_stack_slots * 8 + 0x18);
+				emit_stx(prog, BPF_DW, BPF_REG_FP, BPF_REG_0,
+					 -stack_size);
+
+				if (!nr_stack_slots)
+					first_off = stack_size;
+				stack_size -= 8;
+				nr_stack_slots++;
+			}
+		} else {
+			/* Only copy the arguments on-stack to current
+			 * 'stack_size' and ignore the regs, used to
+			 * prepare the arguments on-stack for orign call.
+			 */
+			if (for_call_origin) {
+				nr_regs += arg_regs;
+				continue;
+			}
 
-		j = next_same_struct ? j : j + 1;
+			/* copy the arguments from regs into stack */
+			for (j = 0; j < arg_regs; j++) {
+				emit_stx(prog, BPF_DW, BPF_REG_FP,
+					 nr_regs == 5 ? X86_REG_R9 : BPF_REG_1 + nr_regs,
+					 -stack_size);
+				stack_size -= 8;
+				nr_regs++;
+			}
+		}
 	}
+
+	clean_stack_garbage(m, prog, nr_stack_slots, first_off);
 }
 
-static void restore_regs(const struct btf_func_model *m, u8 **prog, int nr_regs,
+static void restore_regs(const struct btf_func_model *m, u8 **prog,
 			 int stack_size)
 {
-	int i, j, arg_size;
-	bool next_same_struct = false;
+	int i, j, arg_regs, nr_regs = 0;
 
 	/* Restore function arguments from stack.
 	 * For a function that accepts two pointers the sequence will be:
 	 * EMIT4(0x48, 0x8B, 0x7D, 0xF0); mov rdi,QWORD PTR [rbp-0x10]
 	 * EMIT4(0x48, 0x8B, 0x75, 0xF8); mov rsi,QWORD PTR [rbp-0x8]
+	 *
+	 * The logic here is similar to what we do in save_args()
 	 */
-	for (i = 0, j = 0; i < min(nr_regs, 6); i++) {
-		/* The arg_size is at most 16 bytes, enforced by the verifier. */
-		arg_size = m->arg_size[j];
-		if (arg_size > 8) {
-			arg_size = 8;
-			next_same_struct = !next_same_struct;
+	for (i = 0; i < min_t(int, m->nr_args, MAX_BPF_FUNC_ARGS); i++) {
+		arg_regs = (m->arg_size[i] + 7) / 8;
+		if (nr_regs + arg_regs <= 6) {
+			for (j = 0; j < arg_regs; j++) {
+				emit_ldx(prog, BPF_DW,
+					 nr_regs == 5 ? X86_REG_R9 : BPF_REG_1 + nr_regs,
+					 BPF_REG_FP,
+					 -stack_size);
+				stack_size -= 8;
+				nr_regs++;
+			}
+		} else {
+			stack_size -= 8 * arg_regs;
 		}
 
-		emit_ldx(prog, bytes_to_bpf_size(arg_size),
-			 i == 5 ? X86_REG_R9 : BPF_REG_1 + i,
-			 BPF_REG_FP,
-			 -(stack_size - i * 8));
-
-		j = next_same_struct ? j : j + 1;
+		if (nr_regs >= 6)
+			break;
 	}
 }
 
@@ -1938,7 +2056,10 @@ static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog,
 	/* arg1: mov rdi, progs[i] */
 	emit_mov_imm64(&prog, BPF_REG_1, (long) p >> 32, (u32) (long) p);
 	/* arg2: lea rsi, [rbp - ctx_cookie_off] */
-	EMIT4(0x48, 0x8D, 0x75, -run_ctx_off);
+	if (!is_imm8(-run_ctx_off))
+		EMIT3_off32(0x48, 0x8D, 0xB5, -run_ctx_off);
+	else
+		EMIT4(0x48, 0x8D, 0x75, -run_ctx_off);
 
 	if (emit_rsb_call(&prog, bpf_trampoline_enter(p), prog))
 		return -EINVAL;
@@ -1954,7 +2075,10 @@ static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog,
 	emit_nops(&prog, 2);
 
 	/* arg1: lea rdi, [rbp - stack_size] */
-	EMIT4(0x48, 0x8D, 0x7D, -stack_size);
+	if (!is_imm8(-stack_size))
+		EMIT3_off32(0x48, 0x8D, 0xBD, -stack_size);
+	else
+		EMIT4(0x48, 0x8D, 0x7D, -stack_size);
 	/* arg2: progs[i]->insnsi for interpreter */
 	if (!p->jited)
 		emit_mov_imm64(&prog, BPF_REG_2,
@@ -1984,7 +2108,10 @@ static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog,
 	/* arg2: mov rsi, rbx <- start time in nsec */
 	emit_mov_reg(&prog, true, BPF_REG_2, BPF_REG_6);
 	/* arg3: lea rdx, [rbp - run_ctx_off] */
-	EMIT4(0x48, 0x8D, 0x55, -run_ctx_off);
+	if (!is_imm8(-run_ctx_off))
+		EMIT3_off32(0x48, 0x8D, 0x95, -run_ctx_off);
+	else
+		EMIT4(0x48, 0x8D, 0x55, -run_ctx_off);
 	if (emit_rsb_call(&prog, bpf_trampoline_exit(p), prog))
 		return -EINVAL;
 
@@ -2136,7 +2263,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
 				void *func_addr)
 {
 	int i, ret, nr_regs = m->nr_args, stack_size = 0;
-	int regs_off, nregs_off, ip_off, run_ctx_off;
+	int regs_off, nregs_off, ip_off, run_ctx_off, arg_stack_off, rbx_off;
 	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];
@@ -2150,8 +2277,10 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
 		if (m->arg_flags[i] & BTF_FMODEL_STRUCT_ARG)
 			nr_regs += (m->arg_size[i] + 7) / 8 - 1;
 
-	/* x86-64 supports up to 6 arguments. 7+ can be added in the future */
-	if (nr_regs > 6)
+	/* x86-64 supports up to MAX_BPF_FUNC_ARGS arguments. 1-6
+	 * are passed through regs, the remains are through stack.
+	 */
+	if (nr_regs > MAX_BPF_FUNC_ARGS)
 		return -ENOTSUPP;
 
 	/* Generated trampoline stack layout:
@@ -2170,7 +2299,14 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
 	 *
 	 * RBP - ip_off    [ traced function ]  BPF_TRAMP_F_IP_ARG flag
 	 *
+	 * RBP - rbx_off   [ rbx value       ]  always
+	 *
 	 * RBP - run_ctx_off [ bpf_tramp_run_ctx ]
+	 *
+	 *                     [ stack_argN ]  BPF_TRAMP_F_CALL_ORIG
+	 *                     [ ...        ]
+	 *                     [ stack_arg2 ]
+	 * RBP - arg_stack_off [ stack_arg1 ]
 	 */
 
 	/* room for return value of orig_call or fentry prog */
@@ -2190,9 +2326,26 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
 
 	ip_off = stack_size;
 
+	stack_size += 8;
+	rbx_off = stack_size;
+
 	stack_size += (sizeof(struct bpf_tramp_run_ctx) + 7) & ~0x7;
 	run_ctx_off = stack_size;
 
+	if (nr_regs > 6 && (flags & BPF_TRAMP_F_CALL_ORIG)) {
+		/* the space that used to pass arguments on-stack */
+		stack_size += (nr_regs - get_nr_used_regs(m)) * 8;
+		/* make sure the stack pointer is 16-byte aligned if we
+		 * need pass arguments on stack, which means
+		 *  [stack_size + 8(rbp) + 8(rip) + 8(origin rip)]
+		 * should be 16-byte aligned. Following code depend on
+		 * that stack_size is already 8-byte aligned.
+		 */
+		stack_size += (stack_size % 16) ? 0 : 8;
+	}
+
+	arg_stack_off = stack_size;
+
 	if (flags & BPF_TRAMP_F_SKIP_FRAME) {
 		/* skip patched call instruction and point orig_call to actual
 		 * body of the kernel function.
@@ -2212,8 +2365,14 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
 	x86_call_depth_emit_accounting(&prog, NULL);
 	EMIT1(0x55);		 /* push rbp */
 	EMIT3(0x48, 0x89, 0xE5); /* mov rbp, rsp */
-	EMIT4(0x48, 0x83, 0xEC, stack_size); /* sub rsp, stack_size */
-	EMIT1(0x53);		 /* push rbx */
+	if (!is_imm8(stack_size))
+		/* sub rsp, stack_size */
+		EMIT3_off32(0x48, 0x81, 0xEC, stack_size);
+	else
+		/* sub rsp, stack_size */
+		EMIT4(0x48, 0x83, 0xEC, stack_size);
+	/* mov QWORD PTR [rbp - rbx_off], rbx */
+	emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_6, -rbx_off);
 
 	/* Store number of argument registers of the traced function:
 	 *   mov rax, nr_regs
@@ -2231,7 +2390,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
 		emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -ip_off);
 	}
 
-	save_regs(m, &prog, nr_regs, regs_off);
+	save_args(m, &prog, regs_off, false);
 
 	if (flags & BPF_TRAMP_F_CALL_ORIG) {
 		/* arg1: mov rdi, im */
@@ -2261,7 +2420,8 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
 	}
 
 	if (flags & BPF_TRAMP_F_CALL_ORIG) {
-		restore_regs(m, &prog, nr_regs, regs_off);
+		restore_regs(m, &prog, regs_off);
+		save_args(m, &prog, arg_stack_off, true);
 
 		if (flags & BPF_TRAMP_F_ORIG_STACK) {
 			emit_ldx(&prog, BPF_DW, BPF_REG_0, BPF_REG_FP, 8);
@@ -2302,7 +2462,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
 		}
 
 	if (flags & BPF_TRAMP_F_RESTORE_REGS)
-		restore_regs(m, &prog, nr_regs, regs_off);
+		restore_regs(m, &prog, regs_off);
 
 	/* This needs to be done regardless. If there were fmod_ret programs,
 	 * the return value is only updated on the stack and still needs to be
@@ -2321,7 +2481,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
 	if (save_ret)
 		emit_ldx(&prog, BPF_DW, BPF_REG_0, BPF_REG_FP, -8);
 
-	EMIT1(0x5B); /* pop rbx */
+	emit_ldx(&prog, BPF_DW, BPF_REG_6, BPF_REG_FP, -rbx_off);
 	EMIT1(0xC9); /* leave */
 	if (flags & BPF_TRAMP_F_SKIP_FRAME)
 		/* skip our return address and return to parent */

net/bpf/test_run.c

@@ -565,6 +565,13 @@ __bpf_kfunc int bpf_modify_return_test(int a, int *b)
 	return a + *b;
 }
 
+__bpf_kfunc int bpf_modify_return_test2(int a, int *b, short c, int d,
+					void *e, char f, int g)
+{
+	*b += 1;
+	return a + *b + c + d + (long)e + f + g;
+}
+
 int noinline bpf_fentry_shadow_test(int a)
 {
 	return a + 1;
@@ -600,6 +607,7 @@ __diag_pop();
 
 BTF_SET8_START(bpf_test_modify_return_ids)
 BTF_ID_FLAGS(func, bpf_modify_return_test)
+BTF_ID_FLAGS(func, bpf_modify_return_test2)
 BTF_ID_FLAGS(func, bpf_fentry_test1, KF_SLEEPABLE)
 BTF_SET8_END(bpf_test_modify_return_ids)
 
@@ -667,7 +675,11 @@ int bpf_prog_test_run_tracing(struct bpf_prog *prog,
 	case BPF_MODIFY_RETURN:
 		ret = bpf_modify_return_test(1, &b);
 		if (b != 2)
-			side_effect = 1;
+			side_effect++;
+		b = 2;
+		ret += bpf_modify_return_test2(1, &b, 3, 4, (void *)5, 6, 7);
+		if (b != 2)
+			side_effect++;
 		break;
 	default:
 		goto out;

tools/testing/selftests/bpf/DENYLIST.aarch64

@@ -10,3 +10,5 @@ kprobe_multi_test/link_api_addrs                 # link_fd unexpected link_fd: a
 kprobe_multi_test/link_api_syms                  # link_fd unexpected link_fd: actual -95 < expected 0
 kprobe_multi_test/skel_api                       # libbpf: failed to load BPF skeleton 'kprobe_multi': -3
 module_attach                                    # prog 'kprobe_multi': failed to auto-attach: -95
+fentry_test/fentry_many_args                     # fentry_many_args:FAIL:fentry_many_args_attach unexpected error: -524
+fexit_test/fexit_many_args                       # fexit_many_args:FAIL:fexit_many_args_attach unexpected error: -524

tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c

@@ -34,6 +34,11 @@ struct bpf_testmod_struct_arg_3 {
 	int b[];
 };
 
+struct bpf_testmod_struct_arg_4 {
+	u64 a;
+	int b;
+};
+
 __diag_push();
 __diag_ignore_all("-Wmissing-prototypes",
 		  "Global functions as their definitions will be in bpf_testmod.ko BTF");
@@ -75,6 +80,24 @@ bpf_testmod_test_struct_arg_6(struct bpf_testmod_struct_arg_3 *a) {
 	return bpf_testmod_test_struct_arg_result;
 }
 
+noinline int
+bpf_testmod_test_struct_arg_7(u64 a, void *b, short c, int d, void *e,
+			      struct bpf_testmod_struct_arg_4 f)
+{
+	bpf_testmod_test_struct_arg_result = a + (long)b + c + d +
+		(long)e + f.a + f.b;
+	return bpf_testmod_test_struct_arg_result;
+}
+
+noinline int
+bpf_testmod_test_struct_arg_8(u64 a, void *b, short c, int d, void *e,
+			      struct bpf_testmod_struct_arg_4 f, int g)
+{
+	bpf_testmod_test_struct_arg_result = a + (long)b + c + d +
+		(long)e + f.a + f.b + g;
+	return bpf_testmod_test_struct_arg_result;
+}
+
 __bpf_kfunc void
 bpf_testmod_test_mod_kfunc(int i)
 {
@@ -191,6 +214,20 @@ noinline int bpf_testmod_fentry_test3(char a, int b, u64 c)
 	return a + b + c;
 }
 
+noinline int bpf_testmod_fentry_test7(u64 a, void *b, short c, int d,
+				      void *e, char f, int g)
+{
+	return a + (long)b + c + d + (long)e + f + g;
+}
+
+noinline int bpf_testmod_fentry_test11(u64 a, void *b, short c, int d,
+				       void *e, char f, int g,
+				       unsigned int h, long i, __u64 j,
+				       unsigned long k)
+{
+	return a + (long)b + c + d + (long)e + f + g + h + i + j + k;
+}
+
 int bpf_testmod_fentry_ok;
 
 noinline ssize_t
@@ -206,6 +243,7 @@ bpf_testmod_test_read(struct file *file, struct kobject *kobj,
 	struct bpf_testmod_struct_arg_1 struct_arg1 = {10};
 	struct bpf_testmod_struct_arg_2 struct_arg2 = {2, 3};
 	struct bpf_testmod_struct_arg_3 *struct_arg3;
+	struct bpf_testmod_struct_arg_4 struct_arg4 = {21, 22};
 	int i = 1;
 
 	while (bpf_testmod_return_ptr(i))
@@ -216,6 +254,11 @@ bpf_testmod_test_read(struct file *file, struct kobject *kobj,
 	(void)bpf_testmod_test_struct_arg_3(1, 4, struct_arg2);
 	(void)bpf_testmod_test_struct_arg_4(struct_arg1, 1, 2, 3, struct_arg2);
 	(void)bpf_testmod_test_struct_arg_5();
+	(void)bpf_testmod_test_struct_arg_7(16, (void *)17, 18, 19,
+					    (void *)20, struct_arg4);
+	(void)bpf_testmod_test_struct_arg_8(16, (void *)17, 18, 19,
+					    (void *)20, struct_arg4, 23);
+
 
 	struct_arg3 = kmalloc((sizeof(struct bpf_testmod_struct_arg_3) +
 				sizeof(int)), GFP_KERNEL);
@@ -243,7 +286,11 @@ bpf_testmod_test_read(struct file *file, struct kobject *kobj,
 
 	if (bpf_testmod_fentry_test1(1) != 2 ||
 	    bpf_testmod_fentry_test2(2, 3) != 5 ||
-	    bpf_testmod_fentry_test3(4, 5, 6) != 15)
+	    bpf_testmod_fentry_test3(4, 5, 6) != 15 ||
+	    bpf_testmod_fentry_test7(16, (void *)17, 18, 19, (void *)20,
+			21, 22) != 133 ||
+	    bpf_testmod_fentry_test11(16, (void *)17, 18, 19, (void *)20,
+			21, 22, 23, 24, 25, 26) != 231)
 		goto out;
 
 	bpf_testmod_fentry_ok = 1;

tools/testing/selftests/bpf/prog_tests/fentry_test.c

@@ -2,8 +2,9 @@
 /* Copyright (c) 2019 Facebook */
 #include <test_progs.h>
 #include "fentry_test.lskel.h"
+#include "fentry_many_args.skel.h"
 
-static int fentry_test(struct fentry_test_lskel *fentry_skel)
+static int fentry_test_common(struct fentry_test_lskel *fentry_skel)
 {
 	int err, prog_fd, i;
 	int link_fd;
@@ -37,7 +38,7 @@ static int fentry_test(struct fentry_test_lskel *fentry_skel)
 	return 0;
 }
 
-void test_fentry_test(void)
+static void fentry_test(void)
 {
 	struct fentry_test_lskel *fentry_skel = NULL;
 	int err;
@@ -46,13 +47,47 @@ void test_fentry_test(void)
 	if (!ASSERT_OK_PTR(fentry_skel, "fentry_skel_load"))
 		goto cleanup;
 
-	err = fentry_test(fentry_skel);
+	err = fentry_test_common(fentry_skel);
 	if (!ASSERT_OK(err, "fentry_first_attach"))
 		goto cleanup;
 
-	err = fentry_test(fentry_skel);
+	err = fentry_test_common(fentry_skel);
 	ASSERT_OK(err, "fentry_second_attach");
 
 cleanup:
 	fentry_test_lskel__destroy(fentry_skel);
 }
+
+static void fentry_many_args(void)
+{
+	struct fentry_many_args *fentry_skel = NULL;
+	int err;
+
+	fentry_skel = fentry_many_args__open_and_load();
+	if (!ASSERT_OK_PTR(fentry_skel, "fentry_many_args_skel_load"))
+		goto cleanup;
+
+	err = fentry_many_args__attach(fentry_skel);
+	if (!ASSERT_OK(err, "fentry_many_args_attach"))
+		goto cleanup;
+
+	ASSERT_OK(trigger_module_test_read(1), "trigger_read");
+
+	ASSERT_EQ(fentry_skel->bss->test1_result, 1,
+		  "fentry_many_args_result1");
+	ASSERT_EQ(fentry_skel->bss->test2_result, 1,
+		  "fentry_many_args_result2");
+	ASSERT_EQ(fentry_skel->bss->test3_result, 1,
+		  "fentry_many_args_result3");
+
+cleanup:
+	fentry_many_args__destroy(fentry_skel);
+}
+
+void test_fentry_test(void)
+{
+	if (test__start_subtest("fentry"))
+		fentry_test();
+	if (test__start_subtest("fentry_many_args"))
+		fentry_many_args();
+}

tools/testing/selftests/bpf/prog_tests/fexit_test.c

@@ -2,8 +2,9 @@
 /* Copyright (c) 2019 Facebook */
 #include <test_progs.h>
 #include "fexit_test.lskel.h"
+#include "fexit_many_args.skel.h"
 
-static int fexit_test(struct fexit_test_lskel *fexit_skel)
+static int fexit_test_common(struct fexit_test_lskel *fexit_skel)
 {
 	int err, prog_fd, i;
 	int link_fd;
@@ -37,7 +38,7 @@ static int fexit_test(struct fexit_test_lskel *fexit_skel)
 	return 0;
 }
 
-void test_fexit_test(void)
+static void fexit_test(void)
 {
 	struct fexit_test_lskel *fexit_skel = NULL;
 	int err;
@@ -46,13 +47,47 @@ void test_fexit_test(void)
 	if (!ASSERT_OK_PTR(fexit_skel, "fexit_skel_load"))
 		goto cleanup;
 
-	err = fexit_test(fexit_skel);
+	err = fexit_test_common(fexit_skel);
 	if (!ASSERT_OK(err, "fexit_first_attach"))
 		goto cleanup;
 
-	err = fexit_test(fexit_skel);
+	err = fexit_test_common(fexit_skel);
 	ASSERT_OK(err, "fexit_second_attach");
 
 cleanup:
 	fexit_test_lskel__destroy(fexit_skel);
 }
+
+static void fexit_many_args(void)
+{
+	struct fexit_many_args *fexit_skel = NULL;
+	int err;
+
+	fexit_skel = fexit_many_args__open_and_load();
+	if (!ASSERT_OK_PTR(fexit_skel, "fexit_many_args_skel_load"))
+		goto cleanup;
+
+	err = fexit_many_args__attach(fexit_skel);
+	if (!ASSERT_OK(err, "fexit_many_args_attach"))
+		goto cleanup;
+
+	ASSERT_OK(trigger_module_test_read(1), "trigger_read");
+
+	ASSERT_EQ(fexit_skel->bss->test1_result, 1,
+		  "fexit_many_args_result1");
+	ASSERT_EQ(fexit_skel->bss->test2_result, 1,
+		  "fexit_many_args_result2");
+	ASSERT_EQ(fexit_skel->bss->test3_result, 1,
+		  "fexit_many_args_result3");
+
+cleanup:
+	fexit_many_args__destroy(fexit_skel);
+}
+
+void test_fexit_test(void)
+{
+	if (test__start_subtest("fexit"))
+		fexit_test();
+	if (test__start_subtest("fexit_many_args"))
+		fexit_many_args();
+}

tools/testing/selftests/bpf/prog_tests/get_func_args_test.c

@@ -30,7 +30,9 @@ void test_get_func_args_test(void)
 	prog_fd = bpf_program__fd(skel->progs.fmod_ret_test);
 	err = bpf_prog_test_run_opts(prog_fd, &topts);
 	ASSERT_OK(err, "test_run");
-	ASSERT_EQ(topts.retval, 1234, "test_run");
+
+	ASSERT_EQ(topts.retval >> 16, 1, "test_run");
+	ASSERT_EQ(topts.retval & 0xffff, 1234 + 29, "test_run");
 
 	ASSERT_EQ(skel->bss->test1_result, 1, "test1_result");
 	ASSERT_EQ(skel->bss->test2_result, 1, "test2_result");

tools/testing/selftests/bpf/prog_tests/modify_return.c

@@ -41,6 +41,10 @@ static void run_test(__u32 input_retval, __u16 want_side_effect, __s16 want_ret)
 	ASSERT_EQ(skel->bss->fexit_result, 1, "modify_return fexit_result");
 	ASSERT_EQ(skel->bss->fmod_ret_result, 1, "modify_return fmod_ret_result");
 
+	ASSERT_EQ(skel->bss->fentry_result2, 1, "modify_return fentry_result2");
+	ASSERT_EQ(skel->bss->fexit_result2, 1, "modify_return fexit_result2");
+	ASSERT_EQ(skel->bss->fmod_ret_result2, 1, "modify_return fmod_ret_result2");
+
 cleanup:
 	modify_return__destroy(skel);
 }
@@ -49,9 +53,9 @@ static void run_test(__u32 input_retval, __u16 want_side_effect, __s16 want_ret)
 void serial_test_modify_return(void)
 {
 	run_test(0 /* input_retval */,
-		 1 /* want_side_effect */,
-		 4 /* want_ret */);
+		 2 /* want_side_effect */,
+		 33 /* want_ret */);
 	run_test(-EINVAL /* input_retval */,
 		 0 /* want_side_effect */,
-		 -EINVAL /* want_ret */);
+		 -EINVAL * 2 /* want_ret */);
 }

tools/testing/selftests/bpf/prog_tests/tracing_struct.c

@@ -55,6 +55,25 @@ static void test_fentry(void)
 
 	ASSERT_EQ(skel->bss->t6, 1, "t6 ret");
 
+	ASSERT_EQ(skel->bss->t7_a, 16, "t7:a");
+	ASSERT_EQ(skel->bss->t7_b, 17, "t7:b");
+	ASSERT_EQ(skel->bss->t7_c, 18, "t7:c");
+	ASSERT_EQ(skel->bss->t7_d, 19, "t7:d");
+	ASSERT_EQ(skel->bss->t7_e, 20, "t7:e");
+	ASSERT_EQ(skel->bss->t7_f_a, 21, "t7:f.a");
+	ASSERT_EQ(skel->bss->t7_f_b, 22, "t7:f.b");
+	ASSERT_EQ(skel->bss->t7_ret, 133, "t7 ret");
+
+	ASSERT_EQ(skel->bss->t8_a, 16, "t8:a");
+	ASSERT_EQ(skel->bss->t8_b, 17, "t8:b");
+	ASSERT_EQ(skel->bss->t8_c, 18, "t8:c");
+	ASSERT_EQ(skel->bss->t8_d, 19, "t8:d");
+	ASSERT_EQ(skel->bss->t8_e, 20, "t8:e");
+	ASSERT_EQ(skel->bss->t8_f_a, 21, "t8:f.a");
+	ASSERT_EQ(skel->bss->t8_f_b, 22, "t8:f.b");
+	ASSERT_EQ(skel->bss->t8_g, 23, "t8:g");
+	ASSERT_EQ(skel->bss->t8_ret, 156, "t8 ret");
+
 	tracing_struct__detach(skel);
 destroy_skel:
 	tracing_struct__destroy(skel);

tools/testing/selftests/bpf/prog_tests/trampoline_count.c

@@ -88,8 +88,8 @@ void serial_test_trampoline_count(void)
 	if (!ASSERT_OK(err, "bpf_prog_test_run_opts"))
 		goto cleanup;
 
-	ASSERT_EQ(opts.retval & 0xffff, 4, "bpf_modify_return_test.result");
-	ASSERT_EQ(opts.retval >> 16, 1, "bpf_modify_return_test.side_effect");
+	ASSERT_EQ(opts.retval & 0xffff, 33, "bpf_modify_return_test.result");
+	ASSERT_EQ(opts.retval >> 16, 2, "bpf_modify_return_test.side_effect");
 
 cleanup:
 	for (; i >= 0; i--) {

tools/testing/selftests/bpf/progs/fentry_many_args.c

+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2023 Tencent */
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+__u64 test1_result = 0;
+SEC("fentry/bpf_testmod_fentry_test7")
+int BPF_PROG(test1, __u64 a, void *b, short c, int d, void *e, char f,
+	     int g)
+{
+	test1_result = a == 16 && b == (void *)17 && c == 18 && d == 19 &&
+		e == (void *)20 && f == 21 && g == 22;
+	return 0;
+}
+
+__u64 test2_result = 0;
+SEC("fentry/bpf_testmod_fentry_test11")
+int BPF_PROG(test2, __u64 a, void *b, short c, int d, void *e, char f,
+	     int g, unsigned int h, long i, __u64 j, unsigned long k)
+{
+	test2_result = a == 16 && b == (void *)17 && c == 18 && d == 19 &&
+		e == (void *)20 && f == 21 && g == 22 && h == 23 &&
+		i == 24 && j == 25 && k == 26;
+	return 0;
+}
+
+__u64 test3_result = 0;
+SEC("fentry/bpf_testmod_fentry_test11")
+int BPF_PROG(test3, __u64 a, __u64 b, __u64 c, __u64 d, __u64 e, __u64 f,
+	     __u64 g, __u64 h, __u64 i, __u64 j, __u64 k)
+{
+	test3_result = a == 16 && b == 17 && c == 18 && d == 19 &&
+		e == 20 && f == 21 && g == 22 && h == 23 &&
+		i == 24 && j == 25 && k == 26;
+	return 0;
+}

tools/testing/selftests/bpf/progs/fexit_many_args.c

+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2023 Tencent */
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+__u64 test1_result = 0;
+SEC("fexit/bpf_testmod_fentry_test7")
+int BPF_PROG(test1, __u64 a, void *b, short c, int d, void *e, char f,
+	     int g, int ret)
+{
+	test1_result = a == 16 && b == (void *)17 && c == 18 && d == 19 &&
+		e == (void *)20 && f == 21 && g == 22 && ret == 133;
+	return 0;
+}
+
+__u64 test2_result = 0;
+SEC("fexit/bpf_testmod_fentry_test11")
+int BPF_PROG(test2, __u64 a, void *b, short c, int d, void *e, char f,
+	     int g, unsigned int h, long i, __u64 j, unsigned long k,
+	     int ret)
+{
+	test2_result = a == 16 && b == (void *)17 && c == 18 && d == 19 &&
+		e == (void *)20 && f == 21 && g == 22 && h == 23 &&
+		i == 24 && j == 25 && k == 26 && ret == 231;
+	return 0;
+}
+
+__u64 test3_result = 0;
+SEC("fexit/bpf_testmod_fentry_test11")
+int BPF_PROG(test3, __u64 a, __u64 b, __u64 c, __u64 d, __u64 e, __u64 f,
+	     __u64 g, __u64 h, __u64 i, __u64 j, __u64 k, __u64 ret)
+{
+	test3_result = a == 16 && b == 17 && c == 18 && d == 19 &&
+		e == 20 && f == 21 && g == 22 && h == 23 &&
+		i == 24 && j == 25 && k == 26 && ret == 231;
+	return 0;
+}

tools/testing/selftests/bpf/progs/modify_return.c

@@ -47,3 +47,43 @@ int BPF_PROG(fexit_test, int a, __u64 b, int ret)
 
 	return 0;
 }
+
+static int sequence2;
+
+__u64 fentry_result2 = 0;
+SEC("fentry/bpf_modify_return_test2")
+int BPF_PROG(fentry_test2, int a, int *b, short c, int d, void *e, char f,
+	     int g)
+{
+	sequence2++;
+	fentry_result2 = (sequence2 == 1);
+	return 0;
+}
+
+__u64 fmod_ret_result2 = 0;
+SEC("fmod_ret/bpf_modify_return_test2")
+int BPF_PROG(fmod_ret_test2, int a, int *b, short c, int d, void *e, char f,
+	     int g, int ret)
+{
+	sequence2++;
+	/* This is the first fmod_ret program, the ret passed should be 0 */
+	fmod_ret_result2 = (sequence2 == 2 && ret == 0);
+	return input_retval;
+}
+
+__u64 fexit_result2 = 0;
+SEC("fexit/bpf_modify_return_test2")
+int BPF_PROG(fexit_test2, int a, int *b, short c, int d, void *e, char f,
+	     int g, int ret)
+{
+	sequence2++;
+	/* If the input_reval is non-zero a successful modification should have
+	 * occurred.
+	 */
+	if (input_retval)
+		fexit_result2 = (sequence2 == 3 && ret == input_retval);
+	else
+		fexit_result2 = (sequence2 == 3 && ret == 29);
+
+	return 0;
+}

tools/testing/selftests/bpf/progs/tracing_struct.c

@@ -18,6 +18,11 @@ struct bpf_testmod_struct_arg_3 {
 	int b[];
 };
 
+struct bpf_testmod_struct_arg_4 {
+	u64 a;
+	int b;
+};
+
 long t1_a_a, t1_a_b, t1_b, t1_c, t1_ret, t1_nregs;
 __u64 t1_reg0, t1_reg1, t1_reg2, t1_reg3;
 long t2_a, t2_b_a, t2_b_b, t2_c, t2_ret;
@@ -25,6 +30,9 @@ long t3_a, t3_b, t3_c_a, t3_c_b, t3_ret;
 long t4_a_a, t4_b, t4_c, t4_d, t4_e_a, t4_e_b, t4_ret;
 long t5_ret;
 int t6;
+long t7_a, t7_b, t7_c, t7_d, t7_e, t7_f_a, t7_f_b, t7_ret;
+long t8_a, t8_b, t8_c, t8_d, t8_e, t8_f_a, t8_f_b, t8_g, t8_ret;
+
 
 SEC("fentry/bpf_testmod_test_struct_arg_1")
 int BPF_PROG2(test_struct_arg_1, struct bpf_testmod_struct_arg_2, a, int, b, int, c)
@@ -130,4 +138,50 @@ int BPF_PROG2(test_struct_arg_11, struct bpf_testmod_struct_arg_3 *, a)
 	return 0;
 }
 
+SEC("fentry/bpf_testmod_test_struct_arg_7")
+int BPF_PROG2(test_struct_arg_12, __u64, a, void *, b, short, c, int, d,
+	      void *, e, struct bpf_testmod_struct_arg_4, f)
+{
+	t7_a = a;
+	t7_b = (long)b;
+	t7_c = c;
+	t7_d = d;
+	t7_e = (long)e;
+	t7_f_a = f.a;
+	t7_f_b = f.b;
+	return 0;
+}
+
+SEC("fexit/bpf_testmod_test_struct_arg_7")
+int BPF_PROG2(test_struct_arg_13, __u64, a, void *, b, short, c, int, d,
+	      void *, e, struct bpf_testmod_struct_arg_4, f, int, ret)
+{
+	t7_ret = ret;
+	return 0;
+}
+
+SEC("fentry/bpf_testmod_test_struct_arg_8")
+int BPF_PROG2(test_struct_arg_14, __u64, a, void *, b, short, c, int, d,
+	      void *, e, struct bpf_testmod_struct_arg_4, f, int, g)
+{
+	t8_a = a;
+	t8_b = (long)b;
+	t8_c = c;
+	t8_d = d;
+	t8_e = (long)e;
+	t8_f_a = f.a;
+	t8_f_b = f.b;
+	t8_g = g;
+	return 0;
+}
+
+SEC("fexit/bpf_testmod_test_struct_arg_8")
+int BPF_PROG2(test_struct_arg_15, __u64, a, void *, b, short, c, int, d,
+	      void *, e, struct bpf_testmod_struct_arg_4, f, int, g,
+	      int, ret)
+{
+	t8_ret = ret;
+	return 0;
+}
+
 char _license[] SEC("license") = "GPL";