Re: [PATCH v2 05/14] net/sysctl: Rename kvfree_rcu() to kvfree_rcu_mightsleep()

From: Joel Fernandes
Date: Sun Mar 26 2023 - 08:29:01 EST


On Wed, Mar 15, 2023 at 2:19 PM Joel Fernandes (Google)
<joel@xxxxxxxxxxxxxxxxx> wrote:
>
> From: "Uladzislau Rezki (Sony)" <urezki@xxxxxxxxx>
>
> The kfree_rcu() and kvfree_rcu() macros' single-argument forms are
> deprecated. Therefore switch to the new kfree_rcu_mightsleep() and
> kvfree_rcu_mightsleep() variants. The goal is to avoid accidental use
> of the single-argument forms, which can introduce functionality bugs in
> atomic contexts and latency bugs in non-atomic contexts.
>
> Cc: Eric Dumazet <edumazet@xxxxxxxxxx>
> Cc: David S. Miller <davem@xxxxxxxxxxxxx>

Could anyone from the networking side Ack this patch so we can take it for 6.4?

Eric or David?

- Joel

> Signed-off-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
> Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
> Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
> ---
> net/core/sysctl_net_core.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c
> index 74842b453407..782273bb93c2 100644
> --- a/net/core/sysctl_net_core.c
> +++ b/net/core/sysctl_net_core.c
> @@ -177,7 +177,7 @@ static int rps_sock_flow_sysctl(struct ctl_table *table, int write,
> if (orig_sock_table) {
> static_branch_dec(&rps_needed);
> static_branch_dec(&rfs_needed);
> - kvfree_rcu(orig_sock_table);
> + kvfree_rcu_mightsleep(orig_sock_table);
> }
> }
> }
> @@ -215,7 +215,7 @@ static int flow_limit_cpu_sysctl(struct ctl_table *table, int write,
> lockdep_is_held(&flow_limit_update_mutex));
> if (cur && !cpumask_test_cpu(i, mask)) {
> RCU_INIT_POINTER(sd->flow_limit, NULL);
> - kfree_rcu(cur);
> + kfree_rcu_mightsleep(cur);
> } else if (!cur && cpumask_test_cpu(i, mask)) {
> cur = kzalloc_node(len, GFP_KERNEL,
> cpu_to_node(i));
> --
> 2.40.0.rc1.284.g88254d51c5-goog
>