From 8e37372ad0bea4c9b4712d9943f6ae96cff9491f Mon Sep 17 00:00:00 2001 From: Heiner Kallweit Date: Wed, 11 Oct 2023 09:46:45 +0200 Subject: PCI/ASPM: Fix L1 substate handling in aspm_attr_store_common() aspm_attr_store_common(), which handles sysfs control of ASPM, has the same problem as fb097dcd5a28 ("PCI/ASPM: Disable only ASPM_STATE_L1 when driver disables L1"): disabling L1 adds only ASPM_L1 (but not any of the L1.x substates) to the "aspm_disable" mask. Enabling one substate, e.g., L1.1, via sysfs removes ASPM_L1 from the disable mask. Since disabling L1 via sysfs doesn't add any of the substates to the disable mask, enabling L1.1 actually enables *all* the substates. In this scenario: - Write 0 to "l1_aspm" to disable L1 - Write 1 to "l1_1_aspm" to enable L1.1 the intention is to disable L1 and all L1.x substates, then enable just L1.1, but in fact, *all* L1.x substates are enabled. Fix this by explicitly disabling all the L1.x substates when disabling L1. Fixes: 72ea91afbfb0 ("PCI/ASPM: Add sysfs attributes for controlling ASPM link states") Link: https://lore.kernel.org/r/6ba7dd79-9cfe-4ed0-a002-d99cb842f361@gmail.com Signed-off-by: Heiner Kallweit [bhelgaas: commit log] Signed-off-by: Bjorn Helgaas Cc: stable@vger.kernel.org --- drivers/pci/pcie/aspm.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/pci') diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index dc203b8e5a63..99656d669f00 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -1255,6 +1255,8 @@ 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)); -- cgit v1.2.3