Re: [PATCH v2] xfrm: policy: Read seqcount outside of rcu-read side in xfrm_policy_lookup_bytype
From: Ahmed S. Darwish <hidden>
Date: 2021-05-28 16:45:40
Also in:
linux-rt-users, lkml, stable
On Fri, May 28, 2021, Varad Gautam wrote:
Thead 1 (xfrm_hash_resize) Thread 2 (xfrm_policy_lookup_bytype) rcu_read_lock(); mutex_lock(&hash_resize_mutex); read_seqcount_begin(&xfrm_policy_hash_generation); mutex_lock(&hash_resize_mutex); // block xfrm_bydst_resize(); synchronize_rcu(); // block <RCU stalls in xfrm_policy_lookup_bytype>
...
Fixes: 77cc278f7b20 ("xfrm: policy: Use sequence counters with associated lock")
Signed-off-by: Varad Gautam <redacted>Acked-by: Ahmed S. Darwish <redacted>