From: Keith Busch <keith.busch@intel.com>
Date: Thu, 30 Mar 2017 03:49:17 +0000 (-0500)
Subject: PCI: Short-circuit pci_device_is_present() for disconnected devices
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=fe2bd75b2290bf6acd4b91312697e445668dd773;p=linux.git

PCI: Short-circuit pci_device_is_present() for disconnected devices

If the PCI device is disconnected, return false immediately from
pci_device_is_present().  pci_device_is_present() uses the bus accessors,
so the early return in the device accessors doesn't help here.

Tested-by: Krishna Dhulipala <krishnad@fb.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Wei Zhang <wzhang@fb.com>
---

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 7904d02ffdb97..8ab0a0d3cddb2 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4932,6 +4932,8 @@ bool pci_device_is_present(struct pci_dev *pdev)
 {
 	u32 v;
 
+	if (pci_dev_is_disconnected(pdev))
+		return false;
 	return pci_bus_read_dev_vendor_id(pdev->bus, pdev->devfn, &v, 0);
 }
 EXPORT_SYMBOL_GPL(pci_device_is_present);