[PATCH 4.14 038/209] arm64: smp: Handle errors reported by the firmware

From: Greg Kroah-Hartman
Date: Wed Dec 04 2019 - 13:24:29 EST


From: Suzuki K Poulose <Suzuki.Poulose@xxxxxxx>

[ Upstream commit f357b3a7e17af7736d67d8267edc1ed3d1dd9391 ]

The __cpu_up() routine ignores the errors reported by the firmware
for a CPU bringup operation and looks for the error status set by the
booting CPU. If the CPU never entered the kernel, we could end up
in assuming stale error status, which otherwise would have been
set/cleared appropriately by the booting CPU.

Reported-by: Steve Capper <steve.capper@xxxxxxx>
Cc: Will Deacon <will.deacon@xxxxxxx>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/arm64/kernel/smp.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 0881dfab10f8f..909bf3926fd23 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -144,6 +144,7 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle)
}
} else {
pr_err("CPU%u: failed to boot: %d\n", cpu, ret);
+ return ret;
}

secondary_data.task = NULL;
--
2.20.1