arm64: psci: Avoid printing in cpu_psci_cpu_die()

stable inclusion
from linux-4.19.160
commit 331298e711e7da5c296c55b4e7ec9ee7894126a7

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

[ Upstream commit 891deb87 ]

cpu_psci_cpu_die() is called in the context of the dying CPU, which
will no longer be online or tracked by RCU. It is therefore not generally
safe to call printk() if the PSCI "cpu off" request fails, so remove the
pr_crit() invocation.

Cc: Qian Cai <cai@redhat.com>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20201106103602.9849-2-will@kernel.orgSigned-off-by: NWill Deacon <will@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: NCheng Jian <cj.chengjian@huawei.com>

arch/arm64/kernel/psci.c

@@ -69,7 +69,6 @@ static int cpu_psci_cpu_disable(unsigned int cpu)
 
 static void cpu_psci_cpu_die(unsigned int cpu)
 {
-	int ret;
 	/*
 	 * There are no known implementations of PSCI actually using the
 	 * power state field, pass a sensible default for now.
@@ -77,9 +76,7 @@ static void cpu_psci_cpu_die(unsigned int cpu)
 	u32 state = PSCI_POWER_STATE_TYPE_POWER_DOWN <<
 		    PSCI_0_2_POWER_STATE_TYPE_SHIFT;
 
-	ret = psci_ops.cpu_off(state);
-
-	pr_crit("unable to power off CPU%u (%d)\n", cpu, ret);
+	psci_ops.cpu_off(state);
 }
 
 static int cpu_psci_cpu_kill(unsigned int cpu)