Workaround for HVM suspend issue

(cherry picked from commit 56ea7eaf76)

patches.xen/Revert-xen-avoid-deadlock-in-xenbus-driver.patch

@@ -0,0 +1,52 @@
+From 7eed8836d3046a93848b891399ebbeee1d56e4f5 Mon Sep 17 00:00:00 2001
+From: Simon Gaiser <simon@invisiblethingslab.com>
+Date: Tue, 30 Jan 2018 07:34:49 +0100
+Subject: [PATCH 2/4] Revert "xen: avoid deadlock in xenbus driver"
+
+This reverts commit 1a3fc2c402810bf336882e695abd1678dbc8d279.
+---
+ drivers/xen/xenbus/xenbus_comms.c | 21 +++++++++++----------
+ 1 file changed, 11 insertions(+), 10 deletions(-)
+
+diff --git a/drivers/xen/xenbus/xenbus_comms.c b/drivers/xen/xenbus/xenbus_comms.c
+index 5b081a01779d..856ada5d39c9 100644
+--- a/drivers/xen/xenbus/xenbus_comms.c
++++ b/drivers/xen/xenbus/xenbus_comms.c
+@@ -299,7 +299,17 @@ static int process_msg(void)
+ 		mutex_lock(&xb_write_mutex);
+ 		list_for_each_entry(req, &xs_reply_list, list) {
+ 			if (req->msg.req_id == state.msg.req_id) {
+-				list_del(&req->list);
++				if (req->state == xb_req_state_wait_reply) {
++					req->msg.type = state.msg.type;
++					req->msg.len = state.msg.len;
++					req->body = state.body;
++					req->state = xb_req_state_got_reply;
++					list_del(&req->list);
++					req->cb(req);
++				} else {
++					list_del(&req->list);
++					kfree(req);
++				}
+ 				err = 0;
+ 				break;
+ 			}
+@@ -307,15 +317,6 @@ static int process_msg(void)
+ 		mutex_unlock(&xb_write_mutex);
+ 		if (err)
+ 			goto out;
+-
+-		if (req->state == xb_req_state_wait_reply) {
+-			req->msg.type = state.msg.type;
+-			req->msg.len = state.msg.len;
+-			req->body = state.body;
+-			req->state = xb_req_state_got_reply;
+-			req->cb(req);
+-		} else
+-			kfree(req);
+ 	}
+ 
+ 	mutex_unlock(&xs_response_mutex);
+-- 
+2.15.1
+

patches.xen/Revert-xen-avoid-deadlock-in-xenbus.patch

@@ -0,0 +1,34 @@
+From f9d9d4c0a6bf6d693d882ea99f0e57b0241b3370 Mon Sep 17 00:00:00 2001
+From: Simon Gaiser <simon@invisiblethingslab.com>
+Date: Tue, 30 Jan 2018 07:34:40 +0100
+Subject: [PATCH 1/4] Revert "xen: avoid deadlock in xenbus"
+
+This reverts commit 529871bb3c0675d0b425e2070d5a739db097be98.
+---
+ drivers/xen/xenbus/xenbus_xs.c | 3 +--
+ 1 file changed, 1 insertion(+), 2 deletions(-)
+
+diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c
+index 3e59590c7254..e46080214955 100644
+--- a/drivers/xen/xenbus/xenbus_xs.c
++++ b/drivers/xen/xenbus/xenbus_xs.c
+@@ -857,8 +857,6 @@ static int xenwatch_thread(void *unused)
+ 	struct list_head *ent;
+ 	struct xs_watch_event *event;
+ 
+-	xenwatch_pid = current->pid;
+-
+ 	for (;;) {
+ 		wait_event_interruptible(watch_events_waitq,
+ 					 !list_empty(&watch_events));
+@@ -927,6 +925,7 @@ int xs_init(void)
+ 	task = kthread_run(xenwatch_thread, NULL, "xenwatch");
+ 	if (IS_ERR(task))
+ 		return PTR_ERR(task);
++	xenwatch_pid = task->pid;
+ 
+ 	/* shutdown watches for kexec boot */
+ 	xs_reset_watches();
+-- 
+2.15.1
+

patches.xen/Revert-xenbus-remove-transaction-holder-from-list-be.patch

@@ -0,0 +1,30 @@
+From 9622a541f049137fef086e45cc6ddf4dd56bb99e Mon Sep 17 00:00:00 2001
+From: Simon Gaiser <simon@invisiblethingslab.com>
+Date: Tue, 30 Jan 2018 07:38:17 +0100
+Subject: [PATCH 3/4] Revert "xenbus: remove transaction holder from list
+ before freeing"
+
+This reverts commit ac4cde398a96c1d28b1c28a0f69b6efd892a1c8a.
+---
+ drivers/xen/xenbus/xenbus_dev_frontend.c | 4 +---
+ 1 file changed, 1 insertion(+), 3 deletions(-)
+
+diff --git a/drivers/xen/xenbus/xenbus_dev_frontend.c b/drivers/xen/xenbus/xenbus_dev_frontend.c
+index f3b089b7c0b6..1f4733b80c87 100644
+--- a/drivers/xen/xenbus/xenbus_dev_frontend.c
++++ b/drivers/xen/xenbus/xenbus_dev_frontend.c
+@@ -442,10 +442,8 @@ static int xenbus_write_transaction(unsigned msg_type,
+ 		return xenbus_command_reply(u, XS_ERROR, "ENOENT");
+ 
+ 	rc = xenbus_dev_request_and_reply(&u->u.msg, u);
+-	if (rc && trans) {
+-		list_del(&trans->list);
++	if (rc)
+ 		kfree(trans);
+-	}
+ 
+ out:
+ 	return rc;
+-- 
+2.15.1
+

series.conf

@@ -28,6 +28,12 @@ patches.xen/xen-pciback-add-attribute-to-allow-MSI-enable-flag-w.patch
 # Fix for grant-table in PVH/HVM in 4.14
 patches.xen/xen-Fix-set-clear-_foreign_p2m_mapping-on-autotransl.patch
 
+# Workaround for HVM suspend issue with >= 4.11
+patches.xen/Revert-xen-avoid-deadlock-in-xenbus.patch
+patches.xen/Revert-xen-avoid-deadlock-in-xenbus-driver.patch
+patches.xen/Revert-xenbus-remove-transaction-holder-from-list-be.patch
+patches.xen/Revert-xen-optimize-xenbus-driver-for-multiple-concu.patch
+
 # Hardware-specific fixes, backported from newer kernel and/or developers branches
 patches.backports/v2-2-2-Input-synaptics---Lenovo-X1-Carbon-5-should-use-SMBUS-RMI.patch
 patches.backports/Input-synaptics---add-Intertouch-support-on-X1-Carbon-6th-and-X280.patch