android-mainline/ANDROID-dummy_cpufreq-Implement-get.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Alistair Delva <adelva@google.com>
Date: Mon, 28 Oct 2019 15:07:10 -0700
Subject: ANDROID: dummy_cpufreq: Implement get()

Fixes panic in time_cpufreq_notifier+0x94 caused by notifying the x86
TSC synchronization code that a CPU frequency change has occurred, but
not properly updating policy->cur beforehand, causing a division by
zero.

Link: https://github.com/ClangBuiltLinux/linux/issues/756
Change-Id: I687093bbdb402a13341762bf9d91dd7f9daffe8b
Signed-off-by: Alistair Delva <adelva@google.com>
---
 drivers/cpufreq/dummy-cpufreq.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/cpufreq/dummy-cpufreq.c b/drivers/cpufreq/dummy-cpufreq.c
index 914f3e39ca9b..ea40d5c7a9fa 100644
--- a/drivers/cpufreq/dummy-cpufreq.c
+++ b/drivers/cpufreq/dummy-cpufreq.c
@@ -23,6 +23,11 @@ static int dummy_cpufreq_driver_init(struct cpufreq_policy *policy)
 	return 0;
 }
 
+static unsigned int dummy_cpufreq_get(unsigned int cpu)
+{
+	return 1;
+}
+
 static int dummy_cpufreq_verify(struct cpufreq_policy *policy)
 {
 	return 0;
@@ -32,6 +37,7 @@ static struct cpufreq_driver dummy_cpufreq_driver = {
 	.name = "dummy",
 	.target_index = dummy_cpufreq_target_index,
 	.init = dummy_cpufreq_driver_init,
+	.get = dummy_cpufreq_get,
 	.verify = dummy_cpufreq_verify,
 	.attr = cpufreq_generic_attr,
 };