[PATCH 3/3] pci/hotplug/pnv-php: Disable MSI and PCI device properly
From: Gavin Shan <hidden>
Date: 2017-02-15 23:23:45
Also in:
linux-pci, stable
Subsystem:
linux for powerpc (32-bit and 64-bit), pci subsystem, the rest · Maintainers:
Madhavan Srinivasan, Bjorn Helgaas, Linus Torvalds
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.
Cc: <redacted> # v4.9+
Fixes: 360aebd85a4c ("drivers/pci/hotplug: Support surprise hotplug in powernv driver")
Signed-off-by: Gavin Shan <redacted>
---
drivers/pci/hotplug/pnv_php.c | 22 ++++++++++++++--------
1 file changed, 14 insertions(+), 8 deletions(-)
diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c
index 6d36b76..335a556 100644
--- a/drivers/pci/hotplug/pnv_php.c
+++ b/drivers/pci/hotplug/pnv_php.c@@ -35,9 +35,11 @@ static void pnv_php_register(struct device_node *dn); 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 pnv_php_slot *php_slot) 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 kref *kref) 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); }
@@ -777,7 +783,7 @@ static void pnv_php_init_irq(struct pnv_php_slot *php_slot, int irq) 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; }
@@ -799,7 +805,7 @@ static void pnv_php_init_irq(struct pnv_php_slot *php_slot, int irq) 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; }
--
2.7.4