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authorShivnandan Kumar <quic_kshivnan@quicinc.com>2022-07-15 14:25:39 +0200
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2022-07-26 20:48:33 +0200
commit8d36694245f2aec17f03a5e0b2797953d2e36704 (patch)
treee1b8654f1e8e096dc1b7952cabc27635fc15d65c /kernel/power
parentLinux 5.19-rc8 (diff)
downloadlinux-8d36694245f2aec17f03a5e0b2797953d2e36704.tar.xz
linux-8d36694245f2aec17f03a5e0b2797953d2e36704.zip
PM: QoS: Add check to make sure CPU freq is non-negative
CPU frequency should never be negative. If some client driver calls freq_qos_update_request with a negative value which will be very high in absolute terms, then frequency QoS sets max CPU freq at fmax as it considers it's absolute value but it will add plist node with negative priority. plist node has priority from INT_MIN (highest) to INT_MAX(lowest). Once priority is set as negative, another client will not be able to reduce CPU frequency. Adding check to make sure CPU freq is non-negative will fix this problem. Signed-off-by: Shivnandan Kumar <quic_kshivnan@quicinc.com> [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'kernel/power')
-rw-r--r--kernel/power/qos.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index ec7e1e85923e..af51ed6d45ef 100644
--- a/kernel/power/qos.c
+++ b/kernel/power/qos.c
@@ -531,7 +531,7 @@ int freq_qos_add_request(struct freq_constraints *qos,
{
int ret;
- if (IS_ERR_OR_NULL(qos) || !req)
+ if (IS_ERR_OR_NULL(qos) || !req || value < 0)
return -EINVAL;
if (WARN(freq_qos_request_active(req),
@@ -563,7 +563,7 @@ EXPORT_SYMBOL_GPL(freq_qos_add_request);
*/
int freq_qos_update_request(struct freq_qos_request *req, s32 new_value)
{
- if (!req)
+ if (!req || new_value < 0)
return -EINVAL;
if (WARN(!freq_qos_request_active(req),