Re: [PATCH -tip v8 01/13] ia64: kprobes: Fix to pass correct trampoline address to the handler

From: Ingo Molnar
Date: Mon Jul 05 2021 - 03:46:41 EST



* Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote:

> Commit e792ff804f49 ("ia64: kprobes: Use generic kretprobe trampoline handler")
> missed to pass the wrong trampoline address (it passes the descriptor address
> instead of function entry address).
> This fixes it to pass correct trampoline address to __kretprobe_trampoline_handler().
> This also changes to use correct symbol dereference function to get the
> function address from the kretprobe_trampoline.
>
> Fixes: e792ff804f49 ("ia64: kprobes: Use generic kretprobe trampoline handler")
> Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>

A better changelog:

The following commit:

Commit e792ff804f49 ("ia64: kprobes: Use generic kretprobe trampoline handler")

Passed the wrong trampoline address to __kretprobe_trampoline_handler(): it
passes the descriptor address instead of function entry address.

Pass the right parameter.

Also use correct symbol dereference function to get the function address
from 'kretprobe_trampoline' - an IA64 special.

(Although I realize that much of this goes away just a couple of patches
later.)

Thanks,

Ingo