Re: [PATCH 3/7] riscv: kprobes: Use patch_text_nosync() for insn slots

Björn Töpel
2024-02-19T12:52:41Z

Samuel Holland <samuel.holland@sifive.com> writes:

> These instructions are not yet visible to the rest of the system,
> so there is no need to do the whole stop_machine() dance.
>
> Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
> ---
>
> arch/riscv/kernel/probes/kprobes.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/riscv/kernel/probes/kprobes.c b/arch/riscv/kernel/probes/kprobes.c
> index 2f08c14a933d..cbf8197072bf 100644
> --- a/arch/riscv/kernel/probes/kprobes.c
> +++ b/arch/riscv/kernel/probes/kprobes.c
> @@ -28,9 +28,9 @@ static void __kprobes arch_prepare_ss_slot(struct kprobe *p)
>
> p->ainsn.api.restore = (unsigned long)p->addr + offset;
>
> - patch_text(p->ainsn.api.insn, &p->opcode, 1);
> - patch_text((void *)((unsigned long)(p->ainsn.api.insn) + offset),
> - &insn, 1);
> + patch_text_nosync(p->ainsn.api.insn, &p->opcode, 1);
> + patch_text_nosync(p->ainsn.api.insn + offset,
> + &insn, 1);

Nit: 100 chars lines!

Nice find!

Reviewed-by: Björn Töpel <bjorn@rivosinc.com>