4.17-stable patches

added patches:
	pci-hv-do-not-wait-forever-on-a-device-that-has-disappeared.patch

diff --git a/queue-4.17/pci-hv-do-not-wait-forever-on-a-device-that-has-disappeared.patch b/queue-4.17/pci-hv-do-not-wait-forever-on-a-device-that-has-disappeared.patch
new file mode 100644 (file)
index 0000000..1cc6ff7
--- /dev/null
+++ b/queue-4.17/pci-hv-do-not-wait-forever-on-a-device-that-has-disappeared.patch
@@ -0,0 +1,131 @@
+From c3635da2a336441253c33298b87b3042db100725 Mon Sep 17 00:00:00 2001
+From: Dexuan Cui <decui@microsoft.com>
+Date: Wed, 23 May 2018 21:12:01 +0000
+Subject: PCI: hv: Do not wait forever on a device that has disappeared
+
+From: Dexuan Cui <decui@microsoft.com>
+
+commit c3635da2a336441253c33298b87b3042db100725 upstream.
+
+Before the guest finishes the device initialization, the device can be
+removed anytime by the host, and after that the host won't respond to
+the guest's request, so the guest should be prepared to handle this
+case.
+
+Add a polling mechanism to detect device presence.
+
+Signed-off-by: Dexuan Cui <decui@microsoft.com>
+[lorenzo.pieralisi@arm.com: edited commit log]
+Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
+Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
+Cc: Stephen Hemminger <sthemmin@microsoft.com>
+Cc: K. Y. Srinivasan <kys@microsoft.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/pci/host/pci-hyperv.c |   46 +++++++++++++++++++++++++++++++-----------
+ 1 file changed, 34 insertions(+), 12 deletions(-)
+
+--- a/drivers/pci/host/pci-hyperv.c
++++ b/drivers/pci/host/pci-hyperv.c
+@@ -556,6 +556,26 @@ static void put_pcichild(struct hv_pci_d
+ static void get_hvpcibus(struct hv_pcibus_device *hv_pcibus);
+ static void put_hvpcibus(struct hv_pcibus_device *hv_pcibus);
+ 
++/*
++ * There is no good way to get notified from vmbus_onoffer_rescind(),
++ * so let's use polling here, since this is not a hot path.
++ */
++static int wait_for_response(struct hv_device *hdev,
++                           struct completion *comp)
++{
++      while (true) {
++              if (hdev->channel->rescind) {
++                      dev_warn_once(&hdev->device, "The device is gone.\n");
++                      return -ENODEV;
++              }
++
++              if (wait_for_completion_timeout(comp, HZ / 10))
++                      break;
++      }
++
++      return 0;
++}
++
+ /**
+  * devfn_to_wslot() - Convert from Linux PCI slot to Windows
+  * @devfn:    The Linux representation of PCI slot
+@@ -1568,7 +1588,8 @@ static struct hv_pci_dev *new_pcichild_d
+       if (ret)
+               goto error;
+ 
+-      wait_for_completion(&comp_pkt.host_event);
++      if (wait_for_response(hbus->hdev, &comp_pkt.host_event))
++              goto error;
+ 
+       hpdev->desc = *desc;
+       refcount_set(&hpdev->refs, 1);
+@@ -2069,15 +2090,16 @@ static int hv_pci_protocol_negotiation(s
+                               sizeof(struct pci_version_request),
+                               (unsigned long)pkt, VM_PKT_DATA_INBAND,
+                               VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
++              if (!ret)
++                      ret = wait_for_response(hdev, &comp_pkt.host_event);
++
+               if (ret) {
+                       dev_err(&hdev->device,
+-                              "PCI Pass-through VSP failed sending version reqquest: %#x",
++                              "PCI Pass-through VSP failed to request version: %d",
+                               ret);
+                       goto exit;
+               }
+ 
+-              wait_for_completion(&comp_pkt.host_event);
+-
+               if (comp_pkt.completion_status >= 0) {
+                       pci_protocol_version = pci_protocol_versions[i];
+                       dev_info(&hdev->device,
+@@ -2286,11 +2308,12 @@ static int hv_pci_enter_d0(struct hv_dev
+       ret = vmbus_sendpacket(hdev->channel, d0_entry, sizeof(*d0_entry),
+                              (unsigned long)pkt, VM_PKT_DATA_INBAND,
+                              VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
++      if (!ret)
++              ret = wait_for_response(hdev, &comp_pkt.host_event);
++
+       if (ret)
+               goto exit;
+ 
+-      wait_for_completion(&comp_pkt.host_event);
+-
+       if (comp_pkt.completion_status < 0) {
+               dev_err(&hdev->device,
+                       "PCI Pass-through VSP failed D0 Entry with status %x\n",
+@@ -2330,11 +2353,10 @@ static int hv_pci_query_relations(struct
+ 
+       ret = vmbus_sendpacket(hdev->channel, &message, sizeof(message),
+                              0, VM_PKT_DATA_INBAND, 0);
+-      if (ret)
+-              return ret;
++      if (!ret)
++              ret = wait_for_response(hdev, &comp);
+ 
+-      wait_for_completion(&comp);
+-      return 0;
++      return ret;
+ }
+ 
+ /**
+@@ -2404,11 +2426,11 @@ static int hv_send_resources_allocated(s
+                               size_res, (unsigned long)pkt,
+                               VM_PKT_DATA_INBAND,
+                               VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
++              if (!ret)
++                      ret = wait_for_response(hdev, &comp_pkt.host_event);
+               if (ret)
+                       break;
+ 
+-              wait_for_completion(&comp_pkt.host_event);
+-
+               if (comp_pkt.completion_status < 0) {
+                       ret = -EPROTO;
+                       dev_err(&hdev->device,

diff --git a/queue-4.17/series b/queue-4.17/series
index dbeaffca7ac931bc22898e3dc019711a6e8a068b..684aee1ad0cab2843df96bccdef7dcd2c4e57f1c 100644 (file)
--- a/queue-4.17/series
+++ b/queue-4.17/series
@@ -12,3 +12,4 @@ team-use-netdev_features_t-instead-of-u32.patch
 vrf-check-the-original-netdevice-for-generating-redirect.patch
 net-dsa-b53-fix-for-brcm-tag-issue-in-cygnus-soc.patch
 ipmr-fix-error-path-when-ipmr_new_table-fails.patch
+pci-hv-do-not-wait-forever-on-a-device-that-has-disappeared.patch