When trying to enable a state that is not covered by the policy,
then the change request will be silently ignored. That's not too
nice to the user, therefore reject such attempts explicitly.
Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx>
---
drivers/pci/pcie/aspm.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index b17e5ffd3..cd0f30ca9 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -1224,11 +1224,16 @@ static ssize_t aspm_attr_store_common(struct device *dev,
{
struct pci_dev *pdev = to_pci_dev(dev);
struct pcie_link_state *link = pcie_aspm_get_link(pdev);
+ u32 policy_state = policy_to_aspm_state(link);
bool state_enable;
if (strtobool(buf, &state_enable) < 0)
return -EINVAL;
+ /* reject attempts to enable states not covered by policy */
+ if (state_enable && state & ~policy_state)
+ return -EPERM;
+
down_read(&pci_bus_sem);
mutex_lock(&aspm_lock);
@@ -1241,7 +1246,7 @@ static ssize_t aspm_attr_store_common(struct device *dev,
link->aspm_disable |= state;
}
- pcie_config_aspm_link(link, policy_to_aspm_state(link));
+ pcie_config_aspm_link(link, policy_state);
mutex_unlock(&aspm_lock);
up_read(&pci_bus_sem);
--
2.27.0
