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SubjectRe: [for-next][PATCH 12/16] kprobes: Initialize kprobes at postcore_initcall
On Wed, Jul 03, 2019 at 10:02:05AM -0400, Steven Rostedt wrote:
> > On arm64 kprobes depends on the BRK handler we register in
> > debug_traps_init(), which is an arch_initcall.
> >
> > As of this change, init_krprobes() calls init_test_probes() before
> > that's registered, so we end up hitting a BRK before we can handle it.
>
> Would something like this help?
>
> -- Steve
>
> diff --git a/kernel/kprobes.c b/kernel/kprobes.c
> index 5471efbeb937..0ca6f53c8505 100644
> --- a/kernel/kprobes.c
> +++ b/kernel/kprobes.c
> @@ -2235,6 +2235,8 @@ static struct notifier_block kprobe_module_nb = {
> extern unsigned long __start_kprobe_blacklist[];
> extern unsigned long __stop_kprobe_blacklist[];
>
> +static bool run_kprobe_tests __initdata;
> +
> static int __init init_kprobes(void)
> {
> int i, err = 0;
> @@ -2286,11 +2288,18 @@ static int __init init_kprobes(void)
> kprobes_initialized = (err == 0);
>
> if (!err)
> - init_test_probes();
> + run_kprobe_tests = true;
> return err;
> }
> subsys_initcall(init_kprobes);
>
> +static int __init run_init_test_probes(void)
> +{
> + if (run_kprobe_tests)
> + init_test_probes();

A return 0 here.

> +}
> +module_init(run_init_test_probes);

This does the trick. I prefer your fix as it leaves the arch code
unchanged. In case you need it:

Tested-by: Catalin Marinas <catalin.marinas@arm.com>

Thanks.

--
Catalin

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