Re: [PATCH v13 RESEND 01/14] arm64/ptrace: Refactor syscall_trace_enter/exit() to accept flags parameter

[Linus Walleij]

On Tue, Mar 17, 2026 at 9:20 AM Jinjie Ruan <ruanjinjie@xxxxxxxxxx> wrote:

> Refactor syscall_trace_enter() and syscall_trace_exit() to move thread
> flag reading to the caller. This aligns arm64's syscall trace enter/exit
> function signature with generic entry framework.
>
> [Changes]
> 1. Function signature changes:
>    - syscall_trace_enter(regs) → syscall_trace_enter(regs, flags)
>    - syscall_trace_exit(regs) → syscall_trace_exit(regs, flags)
>
> 2. Move flags reading to caller:
>    - Previously: read_thread_flags() called inside each function.
>    - Now: caller (like el0_svc_common) passes flags as parameter.
>
> 3. Update syscall.c:
>    - el0_svc_common() now passes flags to tracing functions and
>      re-fetches flags before exit to handle potential TIF updates.
>
> [Why this matters]
> - Aligns arm64 with the generic entry interface.
> - Makes future migration to generic entry framework.
>
> No functional changes intended.
>
> Cc: Will Deacon <will@xxxxxxxxxx>
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Reviewed-by: Kevin Brodsky <kevin.brodsky@xxxxxxx>
> Signed-off-by: Jinjie Ruan <ruanjinjie@xxxxxxxxxx>

Reviewed-by: Linus Walleij <linusw@xxxxxxxxxx>

Yours,
Linus Walleij