The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 15becc2b56c6eda3d9bf5ae993bafd5661c1fad1 Mon Sep 17 00:00:00 2001
From: Dexuan Cui decui@microsoft.com Date: Mon, 4 Mar 2019 21:34:48 +0000 Subject: [PATCH] PCI: hv: Add hv_pci_remove_slots() when we unload the driver
When we unload the pci-hyperv host controller driver, the host does not send us a PCI_EJECT message.
In this case we also need to make sure the sysfs PCI slot directory is removed, otherwise a command on a slot file eg:
"cat /sys/bus/pci/slots/2/address"
will trigger a
"BUG: unable to handle kernel paging request"
and, if we unload/reload the driver several times we would end up with stale slot entries in PCI slot directories in /sys/bus/pci/slots/
root@localhost:~# ls -rtl /sys/bus/pci/slots/ total 0 drwxr-xr-x 2 root root 0 Feb 7 10:49 2 drwxr-xr-x 2 root root 0 Feb 7 10:49 2-1 drwxr-xr-x 2 root root 0 Feb 7 10:51 2-2
Add the missing code to remove the PCI slot and fix the current behaviour.
Fixes: a15f2c08c708 ("PCI: hv: support reporting serial number as slot information") Signed-off-by: Dexuan Cui decui@microsoft.com [lorenzo.pieralisi@arm.com: reformatted the log] Signed-off-by: Lorenzo Pieralisi lorenzo.pieralisi@arm.com Reviewed-by: Stephen Hemminger sthemmin@microsoft.com Reviewed-by: Michael Kelley mikelley@microsoft.com Cc: stable@vger.kernel.org
diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c index 30f16b882746..b489412e3502 100644 --- a/drivers/pci/controller/pci-hyperv.c +++ b/drivers/pci/controller/pci-hyperv.c @@ -1486,6 +1486,21 @@ static void hv_pci_assign_slots(struct hv_pcibus_device *hbus) } }
+/* + * Remove entries in sysfs pci slot directory. + */ +static void hv_pci_remove_slots(struct hv_pcibus_device *hbus) +{ + struct hv_pci_dev *hpdev; + + list_for_each_entry(hpdev, &hbus->children, list_entry) { + if (!hpdev->pci_slot) + continue; + pci_destroy_slot(hpdev->pci_slot); + hpdev->pci_slot = NULL; + } +} + /** * create_root_hv_pci_bus() - Expose a new root PCI bus * @hbus: Root PCI bus, as understood by this driver @@ -2680,6 +2695,7 @@ static int hv_pci_remove(struct hv_device *hdev) pci_lock_rescan_remove(); pci_stop_root_bus(hbus->pci_bus); pci_remove_root_bus(hbus->pci_bus); + hv_pci_remove_slots(hbus); pci_unlock_rescan_remove(); hbus->state = hv_pcibus_removed; }