arch: Fix CPU on/off race condition and prevent device hang#7170
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sunghan-chang merged 1 commit intoSamsung:masterfrom Apr 3, 2026
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arch: Fix CPU on/off race condition and prevent device hang#7170sunghan-chang merged 1 commit intoSamsung:masterfrom
sunghan-chang merged 1 commit intoSamsung:masterfrom
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sunghan-chang
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When up_cpu_die is called via SGI3 but up_cpu_on fails, the system currently returns an error. This causes the scheduler to perceive the CPU as alive when it is actually dead. If up_cpu_off is called again in this state, the CPU receiving SGI3 is in die state, resulting in a deadlock. Therefore, when up_cpu_down fails, up_cpu_on must be called again to reactivate the CPU. Additionally, calling up_cpu_on twice leads to psci_cpu_on being invoked twice, which can cause device hang. To prevent this, psci_affinity_info is now used to check CPU state before calling psci_cpu_on. Signed-off-by: eunwoo.nam <eunwoo.nam@samsung.com>
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When up_cpu_die is called via SGI3 but up_cpu_on fails, the system currently returns an error. This causes the scheduler to perceive the CPU as alive when it is actually dead. If up_cpu_off is called again in this state, the CPU receiving SGI3 is in die state, resulting in a deadlock.
Therefore, when up_cpu_down fails, up_cpu_on must be called again to reactivate the CPU.
Additionally, calling up_cpu_on twice leads to psci_cpu_on being invoked twice, which can cause device hang. To prevent this, psci_affinity_info is now used to check CPU state before calling psci_cpu_on.