From: Michael Neuling Date: Wed, 28 Apr 2010 13:39:41 +0000 (+0000) Subject: powerpc/pseries: Only call start-cpu when a CPU is stopped X-Git-Tag: v2.6.34.1~123 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=580506f5514735aa4e6b0d8f8f0dc7db7dcd4044;p=karo-tx-linux.git powerpc/pseries: Only call start-cpu when a CPU is stopped commit aef40e87d866355ffd279ab21021de733242d0d5 upstream. Currently we always call start-cpu irrespective of if the CPU is stopped or not. Unfortunatley on POWER7, firmware seems to not like start-cpu being called when a cpu already been started. This was not the case on POWER6 and earlier. This patch checks to see if the CPU is stopped or not via an query-cpu-stopped-state call, and only calls start-cpu on CPUs which are stopped. This fixes a bug with kexec on POWER7 on PHYP where only the primary thread would make it to the second kernel. Reported-by: Ankita Garg Signed-off-by: Michael Neuling Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/powerpc/platforms/pseries/smp.c b/arch/powerpc/platforms/pseries/smp.c index 4e7f89a84561..c718afbf8c9d 100644 --- a/arch/powerpc/platforms/pseries/smp.c +++ b/arch/powerpc/platforms/pseries/smp.c @@ -82,6 +82,12 @@ static inline int __devinit smp_startup_cpu(unsigned int lcpu) pcpu = get_hard_smp_processor_id(lcpu); + /* Check to see if the CPU out of FW already for kexec */ + if (smp_query_cpu_stopped(pcpu) == QCSS_NOT_STOPPED){ + cpu_set(lcpu, of_spin_map); + return 1; + } + /* Fixup atomic count: it exited inside IRQ handler. */ task_thread_info(paca[lcpu].__current)->preempt_count = 0;