Merge tag 'rcu.6.4.april5.2023.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jfern/linux

Pull RCU updates from Joel Fernandes:

 - Updates and additions to MAINTAINERS files, with Boqun being added to
   the RCU entry and Zqiang being added as an RCU reviewer.

   I have also transitioned from reviewer to maintainer; however, Paul
   will be taking over sending RCU pull-requests for the next merge
   window.

 - Resolution of hotplug warning in nohz code, achieved by fixing
   cpu_is_hotpluggable() through interaction with the nohz subsystem.

   Tick dependency modifications by Zqiang, focusing on fixing usage of
   the TICK_DEP_BIT_RCU_EXP bitmask.

 - Avoid needless calls to the rcu-lazy shrinker for CONFIG_RCU_LAZY=n
   kernels, fixed by Zqiang.

 - Improvements to rcu-tasks stall reporting by Neeraj.

 - Initial renaming of k[v]free_rcu() to k[v]free_rcu_mightsleep() for
   increased robustness, affecting several components like mac802154,
   drbd, vmw_vmci, tracing, and more.

   A report by Eric Dumazet showed that the API could be unknowingly
   used in an atomic context, so we'd rather make sure they know what
   they're asking for by being explicit:

      https://lore.kernel.org/all/20221202052847.2623997-1-edumazet@google.com/

 - Documentation updates, including corrections to spelling,
   clarifications in comments, and improvements to the srcu_size_state
   comments.

 - Better srcu_struct cache locality for readers, by adjusting the size
   of srcu_struct in support of SRCU usage by Christoph Hellwig.

 - Teach lockdep to detect deadlocks between srcu_read_lock() vs
   synchronize_srcu() contributed by Boqun.

   Previously lockdep could not detect such deadlocks, now it can.

 - Integration of rcutorture and rcu-related tools, targeted for v6.4
   from Boqun's tree, featuring new SRCU deadlock scenarios, test_nmis
   module parameter, and more

 - Miscellaneous changes, various code cleanups and comment improvements

* tag 'rcu.6.4.april5.2023.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jfern/linux: (71 commits)
  checkpatch: Error out if deprecated RCU API used
  mac802154: Rename kfree_rcu() to kvfree_rcu_mightsleep()
  rcuscale: Rename kfree_rcu() to kfree_rcu_mightsleep()
  ext4/super: Rename kfree_rcu() to kfree_rcu_mightsleep()
  net/mlx5: Rename kfree_rcu() to kfree_rcu_mightsleep()
  net/sysctl: Rename kvfree_rcu() to kvfree_rcu_mightsleep()
  lib/test_vmalloc.c: Rename kvfree_rcu() to kvfree_rcu_mightsleep()
  tracing: Rename kvfree_rcu() to kvfree_rcu_mightsleep()
  misc: vmw_vmci: Rename kvfree_rcu() to kvfree_rcu_mightsleep()
  drbd: Rename kvfree_rcu() to kvfree_rcu_mightsleep()
  rcu: Protect rcu_print_task_exp_stall() ->exp_tasks access
  rcu: Avoid stack overflow due to __rcu_irq_enter_check_tick() being kprobe-ed
  rcu-tasks: Report stalls during synchronize_srcu() in rcu_tasks_postscan()
  rcu: Permit start_poll_synchronize_rcu_expedited() to be invoked early
  rcu: Remove never-set needwake assignment from rcu_report_qs_rdp()
  rcu: Register rcu-lazy shrinker only for CONFIG_RCU_LAZY=y kernels
  rcu: Fix missing TICK_DEP_MASK_RCU_EXP dependency check
  rcu: Fix set/clear TICK_DEP_BIT_RCU_EXP bitmask race
  rcu/trace: use strscpy() to instead of strncpy()
  tick/nohz: Fix cpu_is_hotpluggable() by checking with nohz subsystem
  ...

3 files changed, 6 insertions, 6 deletions

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 60757ac31701..f49f2a5282e1 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -1615,7 +1615,7 @@ int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info)
 			drbd_send_sync_param(peer_device);
 	}
 
-	kvfree_rcu(old_disk_conf);
+	kvfree_rcu_mightsleep(old_disk_conf);
 	kfree(old_plan);
 	mod_timer(&device->request_timer, jiffies + HZ);
 	goto success;
@@ -2446,7 +2446,7 @@ int drbd_adm_net_opts(struct sk_buff *skb, struct genl_info *info)
 
 	mutex_unlock(&connection->resource->conf_update);
 	mutex_unlock(&connection->data.mutex);
-	kvfree_rcu(old_net_conf);
+	kvfree_rcu_mightsleep(old_net_conf);
 
 	if (connection->cstate >= C_WF_REPORT_PARAMS) {
 		struct drbd_peer_device *peer_device;
@@ -2860,7 +2860,7 @@ int drbd_adm_resize(struct sk_buff *skb, struct genl_info *info)
 		new_disk_conf->disk_size = (sector_t)rs.resize_size;
 		rcu_assign_pointer(device->ldev->disk_conf, new_disk_conf);
 		mutex_unlock(&device->resource->conf_update);
-		kvfree_rcu(old_disk_conf);
+		kvfree_rcu_mightsleep(old_disk_conf);
 		new_disk_conf = NULL;
 	}
 
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 757f4692b5bd..e197b2a465d2 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -3759,7 +3759,7 @@ static int receive_protocol(struct drbd_connection *connection, struct packet_in
 		drbd_info(connection, "peer data-integrity-alg: %s\n",
 			  integrity_alg[0] ? integrity_alg : "(none)");
 
-	kvfree_rcu(old_net_conf);
+	kvfree_rcu_mightsleep(old_net_conf);
 	return 0;
 
 disconnect_rcu_unlock:
@@ -4127,7 +4127,7 @@ static int receive_sizes(struct drbd_connection *connection, struct packet_info
 
 			rcu_assign_pointer(device->ldev->disk_conf, new_disk_conf);
 			mutex_unlock(&connection->resource->conf_update);
-			kvfree_rcu(old_disk_conf);
+			kvfree_rcu_mightsleep(old_disk_conf);
 
 			drbd_info(device, "Peer sets u_size to %lu sectors (old: %lu)\n",
 				 (unsigned long)p_usize, (unsigned long)my_usize);
diff --git a/drivers/block/drbd/drbd_state.c b/drivers/block/drbd/drbd_state.c
index 75d13ea0024f..2aeea295fa28 100644
--- a/drivers/block/drbd/drbd_state.c
+++ b/drivers/block/drbd/drbd_state.c
@@ -2071,7 +2071,7 @@ static int w_after_conn_state_ch(struct drbd_work *w, int unused)
 		conn_free_crypto(connection);
 		mutex_unlock(&connection->resource->conf_update);
 
-		kvfree_rcu(old_conf);
+		kvfree_rcu_mightsleep(old_conf);
 	}
 
 	if (ns_max.susp_fen) {