Commit a1307bba authored Mar 30, 2015 by Heiko Carstens Committed by Martin Schwidefsky Apr 13, 2015

s390/smp: wait until secondaries are active & online



This is the s390 version of 875ebe94 ("powerpc/smp: Wait until secondaries
are active & online").
The race described in length within the commit message is also possible on s390
and every other architecture. So fix this race on s390 as well.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

parent d7441949

arch/s390/kernel/smp.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -818,7 +818,8 @@ int __cpu_up(unsigned int cpu, struct task_struct *tidle)
		pcpu_prepare_secondary(pcpu, cpu);
		pcpu_attach_task(pcpu, tidle);
		pcpu_start_fn(pcpu, smp_start_secondary, NULL);
		while (!cpu_online(cpu))
		/* Wait until cpu puts itself in the online & active maps */
		while (!cpu_online(cpu) \|\| !cpu_active(cpu))
		cpu_relax();
		return 0;
		}