Re: [PATCH v2 12/39] x86/ibt,ftrace: Search for __fentry__ location

From: Steven Rostedt
Date: Wed Mar 02 2022 - 11:01:46 EST


On Wed, 2 Mar 2022 14:20:23 +0100
Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:

> Like so, or is something else needed?
>
> diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
> index 68ecd3e35342..d1b30b5c5c23 100644
> --- a/kernel/trace/ftrace.c
> +++ b/kernel/trace/ftrace.c
> @@ -4980,7 +4980,8 @@ ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove)
> {
> struct ftrace_func_entry *entry;
>
> - if (!ftrace_location(ip))
> + ip = ftrace_location(ip);
> + if (!ip)
> return -EINVAL;

This could possibly work. I'd have to test all this though.

I probably could just take this patch and try it out. You can remove the
"x86/ibt" from the subject, as this patch may be a requirement for that
(include that in the commit log), but it is has no changes to x86/ibt
specifically.

-- Steve


>
> if (remove) {