On Wed, 8 Jan 2025 10:04:55 +0100 Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> wrote: > __module_text_address() can be invoked within a RCU section, there is no > requirement to have preemption disabled. > > Replace the preempt_disable() section around __module_text_address() > with RCU. Hi, Since the below cleanup has been merged, this patch needs to be updated. https://lore.kernel.org/all/20241121-kprobes-preempt-v1-1-fd581ee7fcbb@xxxxxxxxxxxxx/ (may need to change the guard(preempt)() -> guard(rcu)() in the new version.) Thank you, > > Cc: David S. Miller <davem@xxxxxxxxxxxxx> > Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@xxxxxxxxx> > Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx> > Cc: Naveen N Rao <naveen@xxxxxxxxxx> > Cc: linux-trace-kernel@xxxxxxxxxxxxxxx > Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> > --- > kernel/kprobes.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/kprobes.c b/kernel/kprobes.c > index b027a4030976a..22e47a27df4aa 100644 > --- a/kernel/kprobes.c > +++ b/kernel/kprobes.c > @@ -1566,7 +1566,7 @@ static int check_kprobe_address_safe(struct kprobe *p, > if (ret) > return ret; > jump_label_lock(); > - preempt_disable(); > + rcu_read_lock(); > > /* Ensure the address is in a text area, and find a module if exists. */ > *probed_mod = NULL; > @@ -1612,7 +1612,7 @@ static int check_kprobe_address_safe(struct kprobe *p, > } > > out: > - preempt_enable(); > + rcu_read_unlock(); > jump_label_unlock(); > > return ret; > -- > 2.47.1 > -- Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
