parisc: Fix detection of nonsynchronous cr16 cycle counters

For CPUs which have an unknown or invalid CPU location (physical location)
assume that their cycle counters aren't syncronized across CPUs.

Signed-off-by: Helge Deller <deller@gmx.de>
Fixes: c8c3735997a3 ("parisc: Enhance detection of synchronous cr16 clocksources")
Cc: stable@vger.kernel.org # 4.13+
Signed-off-by: Helge Deller <deller@gmx.de>

1 files changed, 4 insertions, 1 deletions

diff --git a/arch/parisc/kernel/time.c b/arch/parisc/kernel/time.c
index 2d956aa0a38a..8c0105a49839 100644
--- a/arch/parisc/kernel/time.c
+++ b/arch/parisc/kernel/time.c
@@ -253,7 +253,10 @@ static int __init init_cr16_clocksource(void)
                 cpu0_loc = per_cpu(cpu_data, 0).cpu_loc;
 
                 for_each_online_cpu(cpu) {
-                        if (cpu0_loc == per_cpu(cpu_data, cpu).cpu_loc)
+                        if (cpu == 0)
+                                continue;
+                        if ((cpu0_loc != 0) &&
+                            (cpu0_loc == per_cpu(cpu_data, cpu).cpu_loc))
                                 continue;
 
                         clocksource_cr16.name = "cr16_unstable";