Re: [PATCH RFC nf-next 09/12] netfilter: ipset: use plain rcu_read_lock

Florian Westphal <[email protected]> Thu, 16 Jul 2026 16:05:52 +0200

Newsgroups	gmane.comp.security.firewalls.netfilter.devel
Message-ID	<[email protected]>

Jozsef Kadlecsik <[email protected]> wrote:
> > No need to disable/reenable softirqs.
> 
> Couldn't then similarly simple spinlocking be used instead the _bh()
> variant? I assume then that there's no need to disable/reenable softirqs in
> those cases either.

I don't think so, the spinlocks are reachable from softirq / timers, so
if you do spin_lock(s) [timer] -> reentry it will deadlock.

rcu_read_lock() can nest, so doesn't have that problem.