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arm64: make secondary_start_kernel() notrace

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[ 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>
This commit is contained in:
Zhizhou Zhang 2018-06-12 17:07:37 +08:00 committed by Greg Kroah-Hartman
parent 7d082f109e
commit d5a362036c
1 changed files with 1 additions and 1 deletions
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arch/arm64/kernel/smp.c
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@ -131,7 +131,7 @@ static void smp_store_cpu_info(unsigned int cpuid)
* 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();