Merge branches 'fixes.2020.04.27a', 'kfree_rcu.2020.04.27a', 'rcu-tasks.2020.04.27a...

fixes.2020.04.27a:  Miscellaneous fixes.
kfree_rcu.2020.04.27a:  Changes related to kfree_rcu().
rcu-tasks.2020.04.27a:  Addition of new RCU-tasks flavors.
stall.2020.04.27a:  RCU CPU stall-warning updates.
torture.2020.05.07a:  Torture-test updates.

diff --cc Documentation/admin-guide/kernel-parameters.txt
Simple merge

diff --cc include/linux/rcutiny.h
Simple merge

diff --cc kernel/rcu/rcu.h
Simple merge

diff --cc kernel/rcu/rcutorture.c
Simple merge

diff --cc kernel/rcu/tree.c
Simple merge

diff --cc kernel/rcu/tree.h
Simple merge

diff --cc kernel/rcu/tree_exp.h
Simple merge

diff --cc kernel/rcu/tree_plugin.h
Simple merge

diff --cc kernel/rcu/tree_stall.h
index 3a7bc99e78e384dbe1e2d1da9c0aa0fa7c94ac0c,4dede00e293639f91eed9abf1f0b1a6095e14179,e1c68a74574f7ad3a22bc4786d7264aace2021a9,535762b0754366c046748cd47829a278785a111c,119ed6afd20feb84e940a0ea01a79ab36d43e423..ae76bd329582929ba2ba988f49f39508ace881bc
--- 1/kernel/rcu/tree_stall.h
--- 2/kernel/rcu/tree_stall.h
--- 3/kernel/rcu/tree_stall.h
--- 4/kernel/rcu/tree_stall.h
--- 5/kernel/rcu/tree_stall.h
+++ b/kernel/rcu/tree_stall.h
@@@@@@ -421,13 -453,13 -455,13 -435,11 -421,13 +501,11 @@@@@@ static void print_other_cpu_stall(unsig
                        pr_err("INFO: Stall ended before state dump start\n");
                } else {
                        j = jiffies;
 ----                   gpa = READ_ONCE(rcu_state.gp_activity);
 ++++                   gpa = data_race(rcu_state.gp_activity);
                        pr_err("All QSes seen, last %s kthread activity %ld (%ld-%ld), jiffies_till_next_fqs=%ld, root ->qsmask %#lx\n",
                               rcu_state.name, j - gpa, j, gpa,
 ----                          READ_ONCE(jiffies_till_next_fqs),
 ++++                          data_race(jiffies_till_next_fqs),
                               rcu_get_root()->qsmask);
--- -                   /* In this case, the current CPU might be at fault. */
--- -                   sched_show_task(current);
                }
        }
        /* Rewrite if needed in case of slow consoles. */

diff --cc kernel/rcu/update.c
Simple merge