5.4-stable patches

added patches:
	xen-netback-move-removal-of-hotplug-status-to-the-right-place.patch

diff --git a/queue-5.4/series b/queue-5.4/series
index bac565575b63db396c2a3b31f096b8a6b8360201..7b6a40bd2a3ae1ff343adc2251325e410f4c41d8 100644 (file)
--- a/queue-5.4/series
+++ b/queue-5.4/series
@@ -10,3 +10,4 @@ usb-serial-f81232-fix-division-by-zero-on-line-speed-change.patch
 usb-serial-f81534-fix-division-by-zero-on-line-speed-change.patch
 igb-initialize-mailbox-message-for-vf-reset.patch
 usb-ulpi-defer-ulpi_register-on-ulpi_read_id-timeout.patch
+xen-netback-move-removal-of-hotplug-status-to-the-right-place.patch

diff --git a/queue-5.4/xen-netback-move-removal-of-hotplug-status-to-the-right-place.patch b/queue-5.4/xen-netback-move-removal-of-hotplug-status-to-the-right-place.patch
new file mode 100644 (file)
index 0000000..9a0a00b
--- /dev/null
+++ b/queue-5.4/xen-netback-move-removal-of-hotplug-status-to-the-right-place.patch
@@ -0,0 +1,69 @@
+From ptyadav@amazon.de  Mon Dec 19 16:41:51 2022
+From: Pratyush Yadav <ptyadav@amazon.de>
+Date: Mon, 19 Dec 2022 16:37:10 +0100
+Subject: xen-netback: move removal of "hotplug-status" to the right place
+To: <stable@vger.kernel.org>
+Cc: "Pratyush Yadav" <ptyadav@amazon.de>, "Greg Kroah-Hartman" <gregkh@linuxfoundation.org>, "Wei Liu" <wei.liu@kernel.org>, "Paul Durrant" <paul@xen.org>, "David S. Miller" <davem@davemloft.net>, "Marek Marczykowski-Górecki" <marmarek@invisiblethingslab.com>, "Jakub Kicinski" <kuba@kernel.org>, "Sasha Levin" <sashal@kernel.org>, "Puranjay Mohan" <pjy@amazon.de>, "Maximilian Heyne" <mheyne@amazon.de>, "Julien Grall" <julien@xen.org>, xen-devel@lists.xenproject.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org
+Message-ID: <20221219153710.23782-1-ptyadav@amazon.de>
+
+From: Pratyush Yadav <ptyadav@amazon.de>
+
+The removal of "hotplug-status" has moved around a bit. First it was
+moved from netback_remove() to hotplug_status_changed() in upstream
+commit 1f2565780e9b ("xen-netback: remove 'hotplug-status' once it has
+served its purpose"). Then the change was reverted in upstream commit
+0f4558ae9187 ("Revert "xen-netback: remove 'hotplug-status' once it has
+served its purpose""), but it moved the removal to backend_disconnect().
+Then the upstream commit c55f34b6aec2 ("xen-netback: only remove
+'hotplug-status' when the vif is actually destroyed") moved it finally
+back to netback_remove(). The thing to note being it is removed
+unconditionally this time around.
+
+The story on v5.4.y adds to this confusion. Commit 60e4e3198ce8 ("Revert
+"xen-netback: remove 'hotplug-status' once it has served its purpose"")
+is backported to v5.4.y but the original commit that it tries to revert
+was never present on 5.4. So the backport incorrectly ends up just
+adding another xenbus_rm() of "hotplug-status" in backend_disconnect().
+
+Now in v5.4.y it is removed in both backend_disconnect() and
+netback_remove(). But it should only be removed in netback_remove(), as
+the upstream version does.
+
+Removing "hotplug-status" in backend_disconnect() causes problems when
+the frontend unilaterally disconnects, as explained in
+c55f34b6aec2 ("xen-netback: only remove 'hotplug-status' when the vif is
+actually destroyed").
+
+Remove "hotplug-status" in the same place as it is done on the upstream
+version to ensure unilateral re-connection of frontend continues to
+work.
+
+Fixes: 60e4e3198ce8 ("Revert "xen-netback: remove 'hotplug-status' once it has served its purpose"")
+Signed-off-by: Pratyush Yadav <ptyadav@amazon.de>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/net/xen-netback/xenbus.c |    3 +--
+ 1 file changed, 1 insertion(+), 2 deletions(-)
+
+--- a/drivers/net/xen-netback/xenbus.c
++++ b/drivers/net/xen-netback/xenbus.c
+@@ -202,10 +202,10 @@ static int netback_remove(struct xenbus_
+       set_backend_state(be, XenbusStateClosed);
+ 
+       unregister_hotplug_status_watch(be);
++      xenbus_rm(XBT_NIL, dev->nodename, "hotplug-status");
+       if (be->vif) {
+               kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE);
+               xen_unregister_watchers(be->vif);
+-              xenbus_rm(XBT_NIL, dev->nodename, "hotplug-status");
+               xenvif_free(be->vif);
+               be->vif = NULL;
+       }
+@@ -435,7 +435,6 @@ static void backend_disconnect(struct ba
+               unsigned int queue_index;
+ 
+               xen_unregister_watchers(vif);
+-              xenbus_rm(XBT_NIL, be->dev->nodename, "hotplug-status");
+ #ifdef CONFIG_DEBUG_FS
+               xenvif_debugfs_delif(vif);
+ #endif /* CONFIG_DEBUG_FS */