Messages in this thread | | | From | Florent Revest <> | Date | Mon, 20 Mar 2023 18:45:08 +0100 | Subject | Re: [PATCH 5/7] ftrace: Store direct called addresses in their ops |
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On Sun, Mar 19, 2023 at 7:55 PM Jiri Olsa <olsajiri@gmail.com> wrote: > > On Sun, Mar 19, 2023 at 01:54:43PM -0400, Steven Rostedt wrote: > > On Sun, 19 Mar 2023 16:29:22 +0100 > > Jiri Olsa <olsajiri@gmail.com> wrote: > > > > > > +++ b/kernel/trace/ftrace.c > > > > @@ -2582,9 +2582,8 @@ ftrace_add_rec_direct(unsigned long ip, unsigned long addr, > > > > static void call_direct_funcs(unsigned long ip, unsigned long pip, > > > > struct ftrace_ops *ops, struct ftrace_regs *fregs) > > > > { > > > > - unsigned long addr; > > > > + unsigned long addr = ops->direct_call; > > > > > > nice, should it be read with READ_ONCE ? > > > > Is there a "read tearing" too? > > don't know, saw the comment in __modify_ftrace_direct and got curious > why it's not in here.. feel free to ignore, I'll look it up > > jirka
Mhh, that's a good question. Based on my current understanding, it seems that it should have a READ_ONCE, indeed. However, I'd like Mark to confirm/deny this. :)
If this should be a READ_ONCE, I can send a v2 series with this fixed.
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