Merge pull request #1 from daniviga/revert-acpi-pts

Reboot/shutdown ACPI PTS issue

README.md

@@ -4,6 +4,10 @@ Tested on a Dell Latitude E5450 (late 2014) with Fedora 22/23 64bit, BIOS A10-A1
 
 Please note: BIOS prior to A06 have a serious issue with de-bouncing/repeating keys under Linux, see http://en.community.dell.com/support-forums/laptop/f/3518/t/19593360. Updating to [A10](http://www.dell.com/support/home/us/en/19/Drivers/DriversDetails?driverId=DHD06&fileId=3469377694&osCode=W764&productCode=latitude-e5450-laptop&languageCode=EN&categoryId=BI) or higher is strongly reccomended.
 
+### Shutdown/reboot issues with kernel >= 4.8
+
+See [kernel/README.md](kernel/README.md)
+
 ### WWAN module
 
 Dell Latitude E5*50 laptops could have a "Dell Wireless 5809e Gobi™ 4G LTE Mobile Broadband Card" WWAN module installed. This WWAN device is based on the Qualcomm Gobi™.

kernel/README.md

@@ -0,0 +1,19 @@
+### Reverting 'ACPI: Execute _PTS before system reboot'
+
+Starting with kernel v4.8 a bug as been introduced that prevents a correct shutdown/reboot of the machine.
+
+The bad commit is:
+
+```
+2c85025c75dfe7ddc2bb33363a998dad59383f94
+ACPI: Execute _PTS before system reboot
+```
+
+All kernels from 4.8.0 are affected at the moment. A patch is provided for reverting this commit.
+
+### More info
+
+- https://bugzilla.redhat.com/show_bug.cgi?id=1393513
+- https://bugzilla.kernel.org/show_bug.cgi?id=187061
+- https://bugzilla.kernel.org/show_bug.cgi?id=151631
+- https://patchwork.kernel.org/patch/9041141/

kernel/revert_pts_before_reboot.patch

@@ -0,0 +1,65 @@
+From c68d3d1812326d3845220564b69faa720c297c73 Mon Sep 17 00:00:00 2001
+From: Daniele Viganò <daniele@vigano.me>
+Date: Thu, 10 Nov 2016 08:11:29 +0100
+Subject: [PATCH] Reverting 2c85025c75dfe7ddc2bb33363a998dad59383f94
+
+---
+ drivers/acpi/sleep.c | 29 ++++++-----------------------
+ 1 file changed, 6 insertions(+), 23 deletions(-)
+
+diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
+index 2b38c1b..7a2e4d4 100644
+--- a/drivers/acpi/sleep.c
++++ b/drivers/acpi/sleep.c
+@@ -47,32 +47,15 @@ static void acpi_sleep_tts_switch(u32 acpi_state)
+ 	}
+ }
+ 
+-static void acpi_sleep_pts_switch(u32 acpi_state)
+-{
+-	acpi_status status;
+-
+-	status = acpi_execute_simple_method(NULL, "\\_PTS", acpi_state);
+-	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
+-		/*
+-		 * OS can't evaluate the _PTS object correctly. Some warning
+-		 * message will be printed. But it won't break anything.
+-		 */
+-		printk(KERN_NOTICE "Failure in evaluating _PTS object\n");
+-	}
+-}
+-
+-static int sleep_notify_reboot(struct notifier_block *this,
++static int tts_notify_reboot(struct notifier_block *this,
+ 			unsigned long code, void *x)
+ {
+ 	acpi_sleep_tts_switch(ACPI_STATE_S5);
+-
+-	acpi_sleep_pts_switch(ACPI_STATE_S5);
+-
+ 	return NOTIFY_DONE;
+ }
+ 
+-static struct notifier_block sleep_notifier = {
+-	.notifier_call	= sleep_notify_reboot,
++static struct notifier_block tts_notifier = {
++	.notifier_call	= tts_notify_reboot,
+ 	.next		= NULL,
+ 	.priority	= 0,
+ };
+@@ -916,9 +899,9 @@ int __init acpi_sleep_init(void)
+ 	pr_info(PREFIX "(supports%s)\n", supported);
+ 
+ 	/*
+-	 * Register the sleep_notifier to reboot notifier list so that the _TTS
+-	 * and _PTS object can also be evaluated when the system enters S5.
++	 * Register the tts_notifier to reboot notifier list so that the _TTS
++	 * object can also be evaluated when the system enters S5.
+ 	 */
+-	register_reboot_notifier(&sleep_notifier);
++	register_reboot_notifier(&tts_notifier);
+ 	return 0;
+ }
+-- 
+2.7.4
+