selftests/bpf: Use at least 10 args in stack argument tests

On arm64, the first 8 arguments are passed in registers (x0-x7), so
tests with 8 or fewer arguments never exercise the native stack argume

selftests/bpf: Use at least 10 args in stack argument tests

On arm64, the first 8 arguments are passed in registers (x0-x7), so
tests with 8 or fewer arguments never exercise the native stack argument
path in the JIT. Increase argument counts to at least 10 across all
BPF-to-BPF subprog and kfunc stack argument tests so that at least 2
arguments land on the arm64 stack.

For the two-callees test, bump foo1 from 8 to 10 and foo2 from 10 to 12
args to preserve the different-stack-depth flavor of the test.

The bpf_kfunc_call_stack_arg_mem kfunc is left unchanged at 7 args to
avoid breaking the precision backtracking test which relies on hardcoded
verifier log instruction indices.

Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20260528161750.1900674-3-puranjay@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

show more ...

selftests/bpf: Add tests for BPF function stack arguments

Add selftests covering stack argument passing for both BPF-to-BPF
subprog calls and kfunc calls with more than 5 arguments. All tests
are gu

selftests/bpf: Add tests for BPF function stack arguments

Add selftests covering stack argument passing for both BPF-to-BPF
subprog calls and kfunc calls with more than 5 arguments. All tests
are guarded by __BPF_FEATURE_STACK_ARGUMENT and __TARGET_ARCH_x86.

BPF-to-BPF subprog call tests (stack_arg.c):
- Scalar stack args
- Pointer stack args
- Mixed pointer/scalar stack args
- Nested calls
- Dynptr stack arg
- Two callees with different stack arg counts
- Async callback

Kfunc call tests (stack_arg_kfunc.c, with bpf_testmod kfuncs):
- Scalar stack args
- Pointer stack args
- Mixed pointer/scalar stack args
- Dynptr stack arg
- Memory buffer + size pair
- Iterator
- Const string pointer
- Timer pointer

Acked-by: Puranjay Mohan <puranjay@kernel.org>
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20260513045127.2397187-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

show more ...