stable inclusion
from stable-5.10.65
commit 527b56d7856fc9a6dd5a0a96bca8ce394b97bfa8
bugzilla: 182361 https://gitee.com/openeuler/kernel/issues/I4EH3U

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=527b56d7856fc9a6dd5a0a96bca8ce394b97bfa8

--------------------------------

[ Upstream commit e6a901a4 ]

The for loop in rcu_print_task_stall() always omits ts[0], which points
to the first task blocking the stalled grace period.  This in turn fails
to count this first task, which means that ndetected will be equal to
zero when all CPUs have passed through their quiescent states and only
one task is blocking the stalled grace period.  This zero value for
ndetected will in turn result in an incorrect "All QSes seen" message:

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu:    Tasks blocked on level-1 rcu_node (CPUs 12-23):
        (detected by 15, t=6504 jiffies, g=164777, q=9011209)
rcu: All QSes seen, last rcu_preempt kthread activity 1 (4295252379-4295252378), jiffies_till_next_fqs=1, root ->qsmask 0x2
BUG: sleeping function called from invalid context at include/linux/uaccess.h:156
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 70613, name: msgstress04
INFO: lockdep is turned off.
Preemption disabled at:
[<ffff8000104031a4>] create_object.isra.0+0x204/0x4b0
CPU: 15 PID: 70613 Comm: msgstress04 Kdump: loaded Not tainted
5.12.2-yoctodev-standard #1
Hardware name: Marvell OcteonTX CN96XX board (DT)
Call trace:
 dump_backtrace+0x0/0x2cc
 show_stack+0x24/0x30
 dump_stack+0x110/0x188
 ___might_sleep+0x214/0x2d0
 __might_sleep+0x7c/0xe0

This commit therefore fixes the loop to include ts[0].

Fixes: c583bcb8 ("rcu: Don't invoke try_invoke_on_locked_down_task() with irqs disabled")
Tested-by: NQais Yousef <qais.yousef@arm.com>
Signed-off-by: NYanfei Xu <yanfei.xu@windriver.com>
Signed-off-by: NPaul E. McKenney <paulmck@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Acked-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>