Skip to contentSkip to conversation

Patch "pci/hotplug/pnv-php: Disable MSI and PCI device properly" has been added to the 4.9-stable tree

PATCH [email protected] 1 participant 1 message Mar 9, 2017

Subsystems (3)
Stable branch PowerPC PCI
lore
Share & tools
lore

[email protected]

author maintainer Applied
#0 lore raw

This is a note to let you know that I've just added the patch titled

pci/hotplug/pnv-php: Disable MSI and PCI device properly

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
pci-hotplug-pnv-php-disable-msi-and-pci-device-properly.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

Quoted 1 line

From 49f4b08e61547a5ccd2db551d994c4503efe5666 Mon Sep 17 00:00:00 2001

From: Gavin Shan <[email protected]>
Date: Thu, 16 Feb 2017 10:22:34 +1100
Subject: pci/hotplug/pnv-php: Disable MSI and PCI device properly

From: Gavin Shan <[email protected]>

commit 49f4b08e61547a5ccd2db551d994c4503efe5666 upstream.

pnv_php_disable_irq() can be called in two paths: Bailing path in pnv_php_enable_irq() or releasing slot. The MSI (or MSIx) interrupts is disabled unconditionally in pnv_php_disable_irq(). It's wrong because that might be enabled by drivers other than pnv-php.

This disables MSI (or MSIx) interrupts and the PCI device only if it was enabled by pnv-php. In the error path of pnv_php_enable_irq(), we rely on the newly added parameter @disable_device. In the path of releasing slot, @pnv_php->irq is checked.

Fixes 360aebd85a4c ("drivers/pci/hotplug: Support surprise hotplug in powernv driver")
Signed-off-by Gavin Shan <[email protected]>
Reviewed-by Andrew Donnellan <[email protected]>
Signed-off-by Michael Ellerman <[email protected]>
Signed-off-by Greg Kroah-Hartman <[email protected]>
---
 drivers/pci/hotplug/pnv_php.c |   22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)
drivers/pci/hotplug/pnv_php.c +14 -8
@@ -35,9 +35,11 @@ static void pnv_php_register(struct devi
 static void pnv_php_unregister_one(struct device_node *dn);
 static void pnv_php_unregister(struct device_node *dn);
 
-static void pnv_php_disable_irq(struct pnv_php_slot *php_slot)
+static void pnv_php_disable_irq(struct pnv_php_slot *php_slot,
+				bool disable_device)
 {
 	struct pci_dev *pdev = php_slot->pdev;
+	int irq = php_slot->irq;
 	u16 ctrl;
 
 	if (php_slot->irq > 0) {

@@ -56,10 +58,14 @@ static void pnv_php_disable_irq(struct p
 		php_slot->wq = NULL;
 	}
 
-	if (pdev->msix_enabled)
-		pci_disable_msix(pdev);
-	else if (pdev->msi_enabled)
-		pci_disable_msi(pdev);
+	if (disable_device || irq > 0) {
+		if (pdev->msix_enabled)
+			pci_disable_msix(pdev);
+		else if (pdev->msi_enabled)
+			pci_disable_msi(pdev);
+
+		pci_disable_device(pdev);
+	}
 }
 
 static void pnv_php_free_slot(struct kref *kref)

@@ -68,7 +74,7 @@ static void pnv_php_free_slot(struct kre
 					struct pnv_php_slot, kref);
 
 	WARN_ON(!list_empty(&php_slot->children));
-	pnv_php_disable_irq(php_slot);
+	pnv_php_disable_irq(php_slot, false);
 	kfree(php_slot->name);
 	kfree(php_slot);
 }

@@ -759,7 +765,7 @@ static void pnv_php_init_irq(struct pnv_
 	php_slot->wq = alloc_workqueue("pciehp-%s", 0, 0, php_slot->name);
 	if (!php_slot->wq) {
 		dev_warn(&pdev->dev, "Cannot alloc workqueue\n");
-		pnv_php_disable_irq(php_slot);
+		pnv_php_disable_irq(php_slot, true);
 		return;
 	}
 

@@ -772,7 +778,7 @@ static void pnv_php_init_irq(struct pnv_
 	ret = request_irq(irq, pnv_php_interrupt, IRQF_SHARED,
 			  php_slot->name, php_slot);
 	if (ret) {
-		pnv_php_disable_irq(php_slot);
+		pnv_php_disable_irq(php_slot, true);
 		dev_warn(&pdev->dev, "Error %d enabling IRQ %d\n", ret, irq);
 		return;
 	}

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/pci-hotplug-pnv-php-disable-msi-and-pci-device-properly.patch queue-4.9/mm-page_alloc-fix-nodes-for-reclaim-in-fast-path.patch