On Wed 23 May 2018 at 01:10, Cong Wang <xiyou.wangc...@gmail.com> wrote: > On Mon, May 21, 2018 at 1:03 PM, Vlad Buslov <vla...@mellanox.com> wrote: >> Initial net_device implementation used ingress_lock spinlock to synchronize >> ingress path of device. This lock was used in both process and bh context. >> In some code paths action map lock was obtained while holding ingress_lock. >> Commit e1e992e52faa ("[NET_SCHED] protect action config/dump from irqs") >> modified actions to always disable bh, while using action map lock, in >> order to prevent deadlock on ingress_lock in softirq. This lock was removed >> from net_device, so disabling bh, while accessing action map, is no longer >> necessary. >> >> Replace all action idr spinlock usage with regular calls that do not >> disable bh. > > While your patch is probably fine, the above justification seems not.
Sorry if I missed something. My justification is based on commit description that added bh disable in subject code. > > In the past, tc actions could be released in BH context because tc > filters use call_rcu(). However, I moved them to a workqueue recently. > So before my change I don't think you can remove the BH protection, > otherwise race with idr_remove()... Found commit series that you described. Will modify commit message accordingly. Thanks, Vlad