diff -Nru seabios-1.8.2/debian/changelog seabios-1.8.2/debian/changelog
--- seabios-1.8.2/debian/changelog	2015-07-30 18:36:24.000000000 +0000
+++ seabios-1.8.2/debian/changelog	2021-05-13 14:08:07.000000000 +0000
@@ -1,3 +1,9 @@
+seabios (1.8.2-1ubuntu2) xenial; urgency=medium
+
+  * Fix missing NMI_DISABLE in rtc_mask() (LP: #1927547)
+
+ -- Heitor Alves de Siqueira <halves@canonical.com>  Thu, 13 May 2021 14:08:07 +0000
+
 seabios (1.8.2-1ubuntu1) wily; urgency=medium
 
   * New debian release.  Remaining change:
diff -Nru seabios-1.8.2/debian/patches/lp1927547-rtc-Disable-NMI-in-rtc_mask.patch seabios-1.8.2/debian/patches/lp1927547-rtc-Disable-NMI-in-rtc_mask.patch
--- seabios-1.8.2/debian/patches/lp1927547-rtc-Disable-NMI-in-rtc_mask.patch	1970-01-01 00:00:00.000000000 +0000
+++ seabios-1.8.2/debian/patches/lp1927547-rtc-Disable-NMI-in-rtc_mask.patch	2021-05-13 14:07:57.000000000 +0000
@@ -0,0 +1,32 @@
+From 3156b71a535e6617fbc60fd6aef09a229aca7327 Mon Sep 17 00:00:00 2001
+From: Kevin O'Connor <kevin@koconnor.net>
+Date: Tue, 1 Sep 2015 19:43:08 -0400
+Subject: [PATCH] rtc: Disable NMI in rtc_mask()
+
+Origin: upstream, https://review.coreboot.org/plugins/gitiles/seabios/+/3156b71a535e661%5E%21
+Bug-Ubuntu: https://bugs.launchpad.net/bugs/1927547
+
+The rtc_mask() function should make sure the NMI disable bit is set
+(just as rtc_read() and rtc_write() do).
+
+Reported-by: Tim Shearer <tim.shearer@overturenetworks.com>
+Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
+---
+ src/hw/rtc.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/src/hw/rtc.c b/src/hw/rtc.c
+index 570a3ad0952a..9649a5a793a7 100644
+--- a/src/hw/rtc.c
++++ b/src/hw/rtc.c
+@@ -30,6 +30,7 @@ rtc_write(u8 index, u8 val)
+ void
+ rtc_mask(u8 index, u8 off, u8 on)
+ {
++    index |= NMI_DISABLE_BIT;
+     outb(index, PORT_CMOS_INDEX);
+     u8 val = inb(PORT_CMOS_DATA);
+     outb((val & ~off) | on, PORT_CMOS_DATA);
+-- 
+2.31.1
+
diff -Nru seabios-1.8.2/debian/patches/series seabios-1.8.2/debian/patches/series
--- seabios-1.8.2/debian/patches/series	2015-07-30 16:16:40.000000000 +0000
+++ seabios-1.8.2/debian/patches/series	2021-05-13 14:07:57.000000000 +0000
@@ -1,2 +1,3 @@
 gcc-5.diff
 turn-vga-allocate-extra-stack-off
+lp1927547-rtc-Disable-NMI-in-rtc_mask.patch