On Wed, Mar 27, 2024 at 3:21 AM Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>
> Add uretprobe syscall test that compares register values before
> and after the uretprobe is hit. It also compares the register
> values seen from attached bpf program.
>
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> ---
> tools/include/linux/compiler.h | 4 +
> .../selftests/bpf/prog_tests/uprobe_syscall.c | 163 ++++++++++++++++++
> .../selftests/bpf/progs/uprobe_syscall.c | 15 ++
> 3 files changed, 182 insertions(+)
> create mode 100644 tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
> create mode 100644 tools/testing/selftests/bpf/progs/uprobe_syscall.c
[...]
> +__naked unsigned long uprobe_syscall_arch_test(void)
> +{
> + asm volatile (
> + "movq $0xdeadbeef, %rax\n"
> + "ret\n"
> + );
> +}
> +
> +__naked void uprobe_syscall_arch(struct pt_regs *before, struct pt_regs *after)
don't you get compiler warnings for using __naked with explicit
function arguments?
> +{
> + asm volatile (
> + "movq %r15, 0(%rdi)\n"
> + "movq %r14, 8(%rdi)\n"
[...]
> + err = uprobe_syscall__attach(skel);
> + if (!ASSERT_OK(err, "uprobe_syscall__attach"))
> + goto cleanup;
> +
> + uprobe_syscall_arch(&before, &after);
uprobe_syscall_arch() doesn't really do an explicit `syscall
uretprobe`, it should work for int3-based uretprobes as well? Let's
call it something a bit more generic then?
Also, I think patch #1 will go through Masami's trace tree, right? But
we can land selftests into bpf-next even before that, given they
should work for both syscall and interrupt based uretprobes.
> +
> + pp = (unsigned long *) &skel->bss->regs;
> + cnt = sizeof(before)/sizeof(*pb);
> +
[...]
