Re: [PATCH net-next v1] ipv6: fix a BUG in rt6_get_pcpu_route() under PREEMPT_RT
From: Paolo Abeni <pabeni@redhat.com>
Date: 2025-12-18 12:25:37
Also in:
linux-rt-devel, lkml
On 12/9/25 1:48 PM, Jiayuan Chen wrote:
quoted hunk ↗ jump to hunk
@@ -2299,11 +2308,13 @@ struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, } else { /* Get a percpu copy */ local_bh_disable(); + migrate_disable(); rt = rt6_get_pcpu_route(&res); if (!rt) rt = rt6_make_pcpu_route(net, &res); + migrate_enable();
AFAICS, this part is not needed: local_bh_disable() ensures migrating is already disabled, if !CONFIG_PREEMPT_RT_NEEDS_BH_LOCK or preemption is disabled, when CONFIG_PREEMPT_RT_NEEDS_BH_LOCK==y Side note: this patch looks suitable for the 'net' tree, please change the subj prefix accordingly in the next revision. Cheers, Paolo