diff options
author | Zhizhou Zhang <zhizhouzhang@asrmicro.com> | 2018-06-12 17:07:37 +0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-08-24 13:12:29 +0200 |
commit | 40137ff99323f88357a55120a4e86471149e3670 (patch) | |
tree | f46b220a2a00837207deefb58d923c090f63686d /arch/arm64 | |
parent | c0a01787462a3a370006cdf5d14d7e7967ad59aa (diff) |
arm64: make secondary_start_kernel() notrace
[ Upstream commit b154886f7892499d0d3054026e19dfb9a731df61 ]
We can't call function trace hook before setup percpu offset.
When entering secondary_start_kernel(), percpu offset has not
been initialized. So this lead hotplug malfunction.
Here is the flow to reproduce this bug:
echo 0 > /sys/devices/system/cpu/cpu1/online
echo function > /sys/kernel/debug/tracing/current_tracer
echo 1 > /sys/kernel/debug/tracing/tracing_on
echo 1 > /sys/devices/system/cpu/cpu1/online
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Zhizhou Zhang <zhizhouzhang@asrmicro.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/arm64')
-rw-r--r-- | arch/arm64/kernel/smp.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index a70f7d3361c4..cfd33f18f437 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -205,7 +205,7 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle) * This is the secondary CPU boot entry. We're using this CPUs * idle thread stack, but a set of temporary page tables. */ -asmlinkage void secondary_start_kernel(void) +asmlinkage notrace void secondary_start_kernel(void) { struct mm_struct *mm = &init_mm; unsigned int cpu = smp_processor_id(); |