[V6,5/5] PCI/ASPM: move link_state cleanup to bridge remove

Commit Message

Sinan Kaya March 29, 2017, 11:04 p.m. UTC

For endpoints, change pcie_aspm_exit_link_state() so it cleans up
the device's own state and disables ASPM if necessary, but doesn't
remove the parent's link_state.

For bridges, change pcie_aspm_exit_link_state() so it frees the
bridge's own link_state.

Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=194895
Signed-off-by: Sinan Kaya <[e-mail]>
---
 drivers/pci/pcie/aspm.c | 20 +++++++++++++++-----
 drivers/pci/remove.c    |  3 +--
 2 files changed, 16 insertions(+), 7 deletions(-)

Comments

Sinan Kaya March 30, 2017, 1:25 p.m. UTC | #1

On 3/29/2017 7:04 PM, Sinan Kaya wrote:
>  	if (!parent || !parent->link_state)
>  		return;
>  
> +	if (pdev->has_secondary_link) {
> +		link = pdev->link_state;

I think I accidentally moved the parent check above this code
and broke the case where you can actually remove the root port.

I'll post v7 with reverting this change.

Patch

diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index a38602a..37ca9b3 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -963,6 +963,21 @@  void pcie_aspm_exit_link_state(struct pci_dev *pdev)
 	if (!parent || !parent->link_state)
 		return;
 
+	if (pdev->has_secondary_link) {
+		link = pdev->link_state;
+		down_read(&pci_bus_sem);
+		mutex_lock(&aspm_lock);
+
+		list_del(&link->sibling);
+		list_del(&link->link);
+
+		/* Clock PM is for endpoint device */
+		free_link_state(link);
+		mutex_unlock(&aspm_lock);
+		up_read(&pci_bus_sem);
+		return;
+	}
+
 	down_read(&pci_bus_sem);
 	mutex_lock(&aspm_lock);
 	/*
@@ -978,11 +993,6 @@  void pcie_aspm_exit_link_state(struct pci_dev *pdev)
 
 	/* All functions are removed, so just disable ASPM for the link */
 	pcie_config_aspm_link(link, 0);
-	list_del(&link->sibling);
-	list_del(&link->link);
-	/* Clock PM is for endpoint device */
-	free_link_state(link);
-
 	/* Recheck latencies and configure upstream links */
 	if (parent_link) {
 		pcie_update_aspm_capable(root);
diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c
index 73a03d3..7e14ebd 100644
--- a/drivers/pci/remove.c
+++ b/drivers/pci/remove.c
@@ -25,8 +25,7 @@  static void pci_stop_dev(struct pci_dev *dev)
 		dev->is_added = 0;
 	}
 
-	if (dev->bus->self)
-		pcie_aspm_exit_link_state(dev);
+	pcie_aspm_exit_link_state(dev);
 }
 
 static void pci_destroy_dev(struct pci_dev *dev)