From 05ff1ba412fd6bd48d56dd4c0baff626533728cc Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 20 Nov 2019 10:33:34 +0100 Subject: PM: QoS: Invalidate frequency QoS requests after removal Switching cpufreq drivers (or switching operation modes of the intel_pstate driver from "active" to "passive" and vice versa) does not work on some x86 systems with ACPI after commit 3000ce3c52f8 ("cpufreq: Use per-policy frequency QoS"), because the ACPI _PPC and thermal code uses the same frequency QoS request object for a given CPU every time a cpufreq driver is registered and freq_qos_remove_request() does not invalidate the request after removing it from its QoS list, so freq_qos_add_request() complains and fails when that request is passed to it again. Fix the issue by modifying freq_qos_remove_request() to clear the qos and type fields of the frequency request pointed to by its argument after removing it from its QoS list so as to invalidate it. Fixes: 3000ce3c52f8 ("cpufreq: Use per-policy frequency QoS") Reported-and-tested-by: Doug Smythies Signed-off-by: Rafael J. Wysocki Acked-by: Viresh Kumar --- kernel/power/qos.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 04e83fdfbe80..a45cba7df0ae 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -814,6 +814,8 @@ EXPORT_SYMBOL_GPL(freq_qos_update_request); */ int freq_qos_remove_request(struct freq_qos_request *req) { + int ret; + if (!req) return -EINVAL; @@ -821,7 +823,11 @@ int freq_qos_remove_request(struct freq_qos_request *req) "%s() called for unknown object\n", __func__)) return -EINVAL; - return freq_qos_apply(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); + ret = freq_qos_apply(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); + req->qos = NULL; + req->type = 0; + + return ret; } EXPORT_SYMBOL_GPL(freq_qos_remove_request); -- cgit