This is a note to let you know that I've just added the patch titled arm64: psci: Avoid printing in cpu_psci_cpu_die() to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: arm64-psci-avoid-printing-in-cpu_psci_cpu_die.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit c1c275ba1f025be6a82117a4632485663de42d65 Author: Will Deacon <will@xxxxxxxxxx> Date: Fri Nov 6 09:57:55 2020 +0000 arm64: psci: Avoid printing in cpu_psci_cpu_die() [ Upstream commit 891deb87585017d526b67b59c15d38755b900fea ] 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@xxxxxxxxxx> Cc: "Paul E. McKenney" <paulmck@xxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Link: https://lore.kernel.org/r/20201106103602.9849-2-will@xxxxxxxxxx Signed-off-by: Will Deacon <will@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index e3713d6fb8e00..bf6142a80cf1a 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c @@ -68,7 +68,6 @@ 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. @@ -76,9 +75,7 @@ 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)