Re: [PATCH net v2 1/2] ipmr: Fix RCU list debugging warning

From: David Miller
Date: Thu May 14 2020 - 21:01:28 EST


From: Amol Grover <frextrite@xxxxxxxxx>
Date: Thu, 14 May 2020 23:31:02 +0530

> ipmr_for_each_table() macro uses list_for_each_entry_rcu()
> for traversing outside of an RCU read side critical section
> but under the protection of rtnl_mutex. Hence, add the
> corresponding lockdep expression to silence the following
> false-positive warning at boot:
>
> [ 4.319347] =============================
> [ 4.319349] WARNING: suspicious RCU usage
> [ 4.319351] 5.5.4-stable #17 Tainted: G E
> [ 4.319352] -----------------------------
> [ 4.319354] net/ipv4/ipmr.c:1757 RCU-list traversed in non-reader section!!
>
> Fixes: f0ad0860d01e ("ipv4: ipmr: support multiple tables")
> Signed-off-by: Amol Grover <frextrite@xxxxxxxxx>

Applied.