Re: [PATCH net 0/2] bond: fix xfrm offload feature during init

[Jianbo Liu]

On 1/9/2025 6:17 PM, Hangbin Liu wrote:
On Thu, Jan 09, 2025 at 05:51:07PM +0800, Jianbo Liu wrote:
No, we don't need. But I am trying to understand what you said in your last
email about adding a new lock, or unlocking spin lock in

I *thought* we need the spin lock in xfrm_state_delete(). So to protect 
xfrm_state,

But not need in bond_ipsec_del_sa() because the state still hold by
xfrm_state_hold(), right?

Hmm, I'm not sure. If xfrm_state_hold() is safe. Why not just remove the spin
lock in xfrm_state_delete(). This is more straightforward. e.g.


We can't remove the spin lock in xfrm_state_delete(), but I think we can 
access the state while holding it, for example, checking (ipsec->xs == 
xs) as you mentioned before, because memory is not freed yet.

diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 67ca7ac955a3..150562abf513 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -784,9 +784,7 @@ int xfrm_state_delete(struct xfrm_state *x)
  {
         int err;

-       spin_lock_bh(&x->lock);
         err = __xfrm_state_delete(x);
-       spin_unlock_bh(&x->lock);

         return err;
  }

We can even rename xfrm_state_delete() to xfrm_state_delete() directly.

Thanks
Hangbin