From: Igor Druzhinin <igor.druzhinin@citrix.com>
Date: Wed, 29 Jan 2020 14:06:10 +0000 (+0100)
Subject: x86/suspend: disable watchdog before calling console_start_sync()
X-Git-Tag: archive/raspbian/4.14.0+80-gd101b417b7-1+rpi1^2~63^2~785
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=5e08f5f56c9955d853c26c985b6fb1fb45d0355d;p=xen.git

x86/suspend: disable watchdog before calling console_start_sync()

... and enable it after exiting S-state. Otherwise accumulated
output in serial buffer might easily trigger the watchdog if it's
still enabled after entering sync transmission mode.

The issue observed on machines which, unfortunately, generate non-0
output in CPU offline callbacks.

Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
---

diff --git a/xen/arch/x86/acpi/power.c b/xen/arch/x86/acpi/power.c
index 8078352312..feb0f6ce20 100644
--- a/xen/arch/x86/acpi/power.c
+++ b/xen/arch/x86/acpi/power.c
@@ -23,6 +23,7 @@
 #include <xen/domain.h>
 #include <xen/console.h>
 #include <xen/iommu.h>
+#include <xen/watchdog.h>
 #include <xen/cpu.h>
 #include <public/platform.h>
 #include <asm/tboot.h>
@@ -223,6 +224,7 @@ static int enter_state(u32 state)
 
     acpi_sleep_prepare(state);
 
+    watchdog_disable();
     console_start_sync();
     printk("Entering ACPI S%d state.\n", state);
 
@@ -235,6 +237,7 @@ static int enter_state(u32 state)
         system_state = SYS_STATE_resume;
         device_power_up(error);
         console_end_sync();
+        watchdog_enable();
         error = -EIO;
         goto done;
     }
@@ -281,6 +284,7 @@ static int enter_state(u32 state)
         tboot_s3_error(error);
 
     console_end_sync();
+    watchdog_enable();
 
     microcode_update_one(true);