From: "Lee, Chun-Yi" <joeyli.kernel@gmail.com>
Date: Tue, 20 Mar 2018 13:51:26 +0800
Subject: [PATCH] ACPI / scan: Send change uevent with offine environmental
 data
Git-commit: 27664c581866c950f31ac007ea2c63fc6e2b29d5
Patch-mainline: v4.17-rc1
References: bsc#1082485

In current design of ACPI container offline, Kernel emits
KOBJ_CHANGE uevent to user space to indidate that the ejection of
the container was triggered by platform. (caa73ea15 patch)

A pure KOBJ_CHANGE uevent is not enough for user space to identify
the purpose. For example, a "udevadm trigger" command can also
be used to emit change event to all udev rules. A udev rule can not
identify that the event is from kernel for offline or from udevadm
for other purpose. Then the offline action in udev rule may also be
triggered by udevadm tool.

So, similar to the change uevent of dock, kernel sends the
KOBJ_CHANGE uevent with a offline environmental data to indicate
purpose. It's useful by udev rule for using ENV{EVENT} filter.

Acked-by: Michal Hocko <mhocko@suse.com>
Tested-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: "Lee, Chun-Yi" <jlee@suse.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/acpi/scan.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -115,6 +115,7 @@ bool acpi_scan_is_offline(struct acpi_de
 {
 	struct acpi_device_physical_node *pn;
 	bool offline = true;
+	char *envp[] = { "EVENT=offline", NULL };
 
 	/*
 	 * acpi_container_offline() calls this for all of the container's
@@ -125,7 +126,7 @@ bool acpi_scan_is_offline(struct acpi_de
 	list_for_each_entry(pn, &adev->physical_node_list, node)
 		if (device_supports_offline(pn->dev) && !pn->dev->offline) {
 			if (uevent)
-				kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
+				kobject_uevent_env(&pn->dev->kobj, KOBJ_CHANGE, envp);
 
 			offline = false;
 			break;