| Message ID | 6ba7dd79-9cfe-4ed0-a002-d99cb842f361@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | PCI/ASPM: Fix L1 sub-state handling in aspm_attr_store_common | expand |
On Wed, Oct 11, 2023 at 09:46:45AM +0200, Heiner Kallweit wrote: > So far we may see an unexpected behavior regard L1 sub-states. > Following scenario: > > Write 0 to "l1_aspm" to disable L1 > Write 1 to "l1_1_aspm" to enable L1.1 > > Intention of step 1 is to implicitly disable also L1.1 and L1.2. > However after step 2 L1.2 is unexpectedly enabled. > > Fix this by explicitly disabling L1 sub-states when disabling L1. > > Fixes: 72ea91afbfb0 ("PCI/ASPM: Add sysfs attributes for controlling ASPM link states") > Link: https://lore.kernel.org/linux-pci/20231002151452.GA560499@bhelgaas/ > Cc: stable@vger.kernel.org > Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Applied to pci/aspm for v6.7, thanks again. > --- > Splitted-out part of original patch according to linked discussion. > --- > drivers/pci/pcie/aspm.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c > index 530c3bb5708c..fc18e42f0a6e 100644 > --- a/drivers/pci/pcie/aspm.c > +++ b/drivers/pci/pcie/aspm.c > @@ -1248,6 +1248,8 @@ static ssize_t aspm_attr_store_common(struct device *dev, > link->aspm_disable &= ~ASPM_STATE_L1; > } else { > link->aspm_disable |= state; > + if (state & ASPM_STATE_L1) > + link->aspm_disable |= ASPM_STATE_L1SS; > } > > pcie_config_aspm_link(link, policy_to_aspm_state(link)); > -- > 2.42.0 >
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index 530c3bb5708c..fc18e42f0a6e 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -1248,6 +1248,8 @@ static ssize_t aspm_attr_store_common(struct device *dev, link->aspm_disable &= ~ASPM_STATE_L1; } else { link->aspm_disable |= state; + if (state & ASPM_STATE_L1) + link->aspm_disable |= ASPM_STATE_L1SS; } pcie_config_aspm_link(link, policy_to_aspm_state(link));
So far we may see an unexpected behavior regard L1 sub-states. Following scenario: Write 0 to "l1_aspm" to disable L1 Write 1 to "l1_1_aspm" to enable L1.1 Intention of step 1 is to implicitly disable also L1.1 and L1.2. However after step 2 L1.2 is unexpectedly enabled. Fix this by explicitly disabling L1 sub-states when disabling L1. Fixes: 72ea91afbfb0 ("PCI/ASPM: Add sysfs attributes for controlling ASPM link states") Link: https://lore.kernel.org/linux-pci/20231002151452.GA560499@bhelgaas/ Cc: stable@vger.kernel.org Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> --- Splitted-out part of original patch according to linked discussion. --- drivers/pci/pcie/aspm.c | 2 ++ 1 file changed, 2 insertions(+)