From f3787e99034ed633a5ff85c19447d311941d48b6 Mon Sep 17 00:00:00 2001
From: Justinien Bouron <justinien.bouron@epfl.ch>
Date: Sun, 10 Mar 2019 04:48:09 -0700
Subject: [PATCH] Fix division by 0 in get_cpu_ticks.

---
 minix/kernel/arch/i386/arch_clock.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/minix/kernel/arch/i386/arch_clock.c b/minix/kernel/arch/i386/arch_clock.c
index 8573e42f7..54959324c 100644
--- a/minix/kernel/arch/i386/arch_clock.c
+++ b/minix/kernel/arch/i386/arch_clock.c
@@ -434,7 +434,11 @@ get_cpu_ticks(unsigned int cpu, uint64_t ticks[CPUSTATES])
 {
 	int i;
 
-	/* TODO: make this inter-CPU safe! */
-	for (i = 0; i < CPUSTATES; i++)
-		ticks[i] = tsc_per_state[cpu][i] / tsc_per_tick[cpu];
+	for (i = 0; i < CPUSTATES; i++) {
+		/* Avoid divide by 0. */
+		if (tsc_per_tick[cpu])
+			ticks[i] = tsc_per_state[cpu][i] / tsc_per_tick[cpu];
+		else
+			ticks[i] = 0;
+	}
 }