Re: [PATCH v9 03/16] arm64/ptrace: Return early for ptrace_report_syscall_entry() error

[Kevin Brodsky]

On 12/12/2025 05:00, Jinjie Ruan wrote:
> On 2025/12/9 21:46, Kevin Brodsky wrote:
>> On 04/12/2025 09:21, Jinjie Ruan wrote:
>>> The generic entry abort the syscall_trace_enter() sequence if
>>> ptrace_report_syscall_entry() errors out, but arm64 not.
>>>
>>> As the ptrace_report_syscall_entry() comment said, the calling arch code
>>> should abort the system call and must prevent normal entry so no system
>>> call is made if ptrace_report_syscall_entry() return nonzero.
>> This patch is now in the right position, which means that arm64 does
>> abort the syscall already without this patch. What we're changing here
>> is that the tracing sequence is interrupted. The comment you're
>> referring to says nothing about tracing so I'm not sure it helps to
>> refer to it.
> I think “must prevent normal entry ”means When ptrace requests
> interception, all subsequent processing, including audit and seccomp,
> should completely bypassed.

Fair enough, let's just make sure the commit message doesn't imply that
arm64 performs a syscall before this patch.

- Kevin