The current implementation of ipi_cpu_stop() is just a tight infinite loop around cpu_relax(). Add a check for a valid cpu_die method of the appropriate cpu_operations structure, and if a valid method is found, transfer control to that method. The core kexec code calls the arch specific machine_shutdown() routine to shutdown any SMP secondary CPUs. The current implementation of the arm64 machine_shutdown() uses smp_send_stop(), which ultimately runs ipi_cpu_stop() on the secondary CPUs. The infinite loop implementation of the current ipi_cpu_stop() does not have any mechanism to get the CPU into a state compatable with a kexec re-boot. Signed-off-by: Geoff Levand <geoff at infradead.org> --- arch/arm64/kernel/smp.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index f0a141d..020bbd5 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -508,6 +508,14 @@ static void ipi_cpu_stop(unsigned int cpu) local_irq_disable(); + /* If we have the cup_ops use them. */ + + if (cpu_ops[cpu]->cpu_disable && cpu_ops[cpu]->cpu_die + && !cpu_ops[cpu]->cpu_disable(cpu)) + cpu_ops[cpu]->cpu_die(cpu); + + /* Spin here if the cup_ops fail. */ + while (1) cpu_relax(); } -- 1.9.1
