Re: [RFC PATCH 03/14] arm: kprobes: Use generic kretprobe trampoline handler

peterz
2020-08-26T14:10:49Z

On Wed, Aug 26, 2020 at 04:08:52PM +0200, peterz@infradead.org wrote:
> On Wed, Aug 26, 2020 at 10:46:43PM +0900, Masami Hiramatsu wrote:
> > static __used __kprobes void *trampoline_handler(struct pt_regs *regs)
> > {
> > + return (void *)kretprobe_trampoline_handler(regs,
> > + (unsigned long)&kretprobe_trampoline,
> > + regs->ARM_fp);
> > }
>
> Does it make sense to have the generic code have a weak
> trampoline_handler() implemented like the above? It looks like a number
> of architectures have this trivial variant and it seems pointless to
> duplicate this.

Argh, I replied to the wrong variant, I mean the one that uses
kernel_stack_pointer(regs).

Then the architecture only needs to implement kernel_stack_pointer() if
there is nothing else to do.