Messages in this thread Patch in this message | | | Date | Mon, 14 Nov 2022 12:20:40 -0500 | From | Steven Rostedt <> | Subject | Re: [PATCH] tracepoint: Allow livepatch module add trace event |
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On Wed, 2 Nov 2022 16:02:36 +0000 Jianlin Lv <iecedge@gmail.com> wrote:
> In the case of keeping the system running, the preferred method for > tracing the kernel is dynamic tracing (kprobe), but the drawback of > this method is that events are lost, especially when tracing packages > in the network stack. > > Livepatching provides a potential solution, which is to reimplement the > function you want to replace and insert a static tracepoint. > In such a way, custom stable static tracepoints can be expanded without > rebooting the system.
Well that's definitely one way to implement dynamic trace events! :-D
-- Steve
> > Signed-off-by: Jianlin Lv <iecedge@gmail.com> > --- > kernel/tracepoint.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c > index f23144af5743..8d1507dd0724 100644 > --- a/kernel/tracepoint.c > +++ b/kernel/tracepoint.c > @@ -571,8 +571,8 @@ static void for_each_tracepoint_range( > bool trace_module_has_bad_taint(struct module *mod) > { > return mod->taints & ~((1 << TAINT_OOT_MODULE) | (1 << TAINT_CRAP) | > - (1 << TAINT_UNSIGNED_MODULE) | > - (1 << TAINT_TEST)); > + (1 << TAINT_UNSIGNED_MODULE) | (1 << TAINT_TEST) | > + (1 << TAINT_LIVEPATCH)); > } > > static BLOCKING_NOTIFIER_HEAD(tracepoint_notify_list);
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