diff --git a/_gdb.spec.Patch.include b/_gdb.spec.Patch.include
index ee35a62..353356e 100644
--- a/_gdb.spec.Patch.include
+++ b/_gdb.spec.Patch.include
@@ -523,3 +523,7 @@ Patch125: gdb-rhbz1540559-gdbaddindex-glibcdebug-regression.patch
 # Fix ppc64 stwux encoding as found by gcc-8.0 -Werror=tautological-compare.
 Patch126: gdb-ppc64-stwux-tautological-compare.patch
 
+# [s390x] Backport arch12 instructions decoding (RH BZ 1553104).
+# =fedoratest
+Patch127: gdb-rhbz1553104-s390x-arch12-test.patch
+
diff --git a/_gdb.spec.patch.include b/_gdb.spec.patch.include
index 1bc02ff..28c6d1f 100644
--- a/_gdb.spec.patch.include
+++ b/_gdb.spec.patch.include
@@ -124,3 +124,4 @@
 %patch124 -p1
 %patch125 -p1
 %patch126 -p1
+%patch127 -p1
diff --git a/_patch_order b/_patch_order
index f3a5edf..91c68da 100644
--- a/_patch_order
+++ b/_patch_order
@@ -124,3 +124,4 @@ gdb-archer.patch
 gdb-vla-intel-fix-print-char-array.patch
 gdb-rhbz1540559-gdbaddindex-glibcdebug-regression.patch
 gdb-ppc64-stwux-tautological-compare.patch
+gdb-rhbz1553104-s390x-arch12-test.patch
diff --git a/gdb-rhbz1553104-s390x-arch12-test.patch b/gdb-rhbz1553104-s390x-arch12-test.patch
new file mode 100644
index 0000000..3266ba8
--- /dev/null
+++ b/gdb-rhbz1553104-s390x-arch12-test.patch
@@ -0,0 +1,97 @@
+From FEDORA_PATCHES Mon Sep 17 00:00:00 2001
+From: Jan Kratochvil <jan.kratochvil@redhat.com>
+Date: Fri, 23 Mar 2018 20:42:44 +0100
+Subject: gdb-rhbz1553104-s390x-arch12-test.patch
+
+FileName: gdb-rhbz1553104-s390x-arch12-test.patch
+
+;; [s390x] Backport arch12 instructions decoding (RH BZ 1553104).
+;; =fedoratest
+---
+ gdb/testsuite/gdb.arch/s390x-arch12.S    |  4 ++++
+ gdb/testsuite/gdb.arch/s390x-arch12.exp  | 34 ++++++++++++++++++++++++++++++++
+ gdb/testsuite/gdb.arch/s390x-arch12.o.uu | 20 +++++++++++++++++++
+ 3 files changed, 58 insertions(+)
+ create mode 100644 gdb/testsuite/gdb.arch/s390x-arch12.S
+ create mode 100644 gdb/testsuite/gdb.arch/s390x-arch12.exp
+ create mode 100644 gdb/testsuite/gdb.arch/s390x-arch12.o.uu
+
+diff --git a/gdb/testsuite/gdb.arch/s390x-arch12.S b/gdb/testsuite/gdb.arch/s390x-arch12.S
+new file mode 100644
+index 0000000000..cc1506eebf
+--- /dev/null
++++ b/gdb/testsuite/gdb.arch/s390x-arch12.S
+@@ -0,0 +1,4 @@
++.text
++.globl load_guarded
++load_guarded:
++.byte 0xeb,0xbf,0xf0,0x58,0x00,0x24,0xe3,0xf0,0xff,0x50,0xff,0x71,0xb9,0x04,0x00,0xbf,0xe3,0x20,0xb0,0xa0,0x00,0x24,0xe3,0x10,0xb0,0xa0,0x00,0x04,0xe3,0x10,0x10,0x00,0x00,0x4c,0xe3,0x10,0xb0,0xa8,0x00,0x24,0xe3,0x10,0xb0,0xa8,0x00,0x04,0xb9,0x04,0x00,0x21,0xe3,0x40,0xb1,0x20,0x00,0x04,0xeb,0xbf,0xb1,0x08,0x00,0x04,0x07,0xf4
+diff --git a/gdb/testsuite/gdb.arch/s390x-arch12.exp b/gdb/testsuite/gdb.arch/s390x-arch12.exp
+new file mode 100644
+index 0000000000..4e902ff960
+--- /dev/null
++++ b/gdb/testsuite/gdb.arch/s390x-arch12.exp
+@@ -0,0 +1,34 @@
++# Copyright 2018 Free Software Foundation, Inc.
++
++# This program is free software; you can redistribute it and/or modify
++# it under the terms of the GNU General Public License as published by
++# the Free Software Foundation; either version 3 of the License, or
++# (at your option) any later version.
++#
++# This program is distributed in the hope that it will be useful,
++# but WITHOUT ANY WARRANTY; without even the implied warranty of
++# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
++# GNU General Public License for more details.
++#
++# You should have received a copy of the GNU General Public License
++# along with this program.  If not, see <http://www.gnu.org/licenses/>.
++
++#if { ![istarget s390x-*linux-*] || ![is_lp64_target] } {
++#    verbose "Skipping s390x-prologue-skip.exp"
++#    return
++#}
++
++set testfile "s390x-arch12"
++set uufile "${srcdir}/${subdir}/${testfile}.o.uu"
++set ofile "${srcdir}/${subdir}/${testfile}.o"
++
++if { [catch "system \"uudecode -o ${ofile} ${uufile}\"" ] != 0 } {
++    untested "failed uudecode"
++    return -1
++}
++
++gdb_exit
++gdb_start
++gdb_load $ofile
++
++gdb_test "disas load_guarded" " <\\+28>:\tlgg\t%r1,0\\(%r1\\)\r\n\[^\r\n\]* <\\+34>:\tstg\t%r1,168\\(%r11\\)\r\n.*"
+diff --git a/gdb/testsuite/gdb.arch/s390x-arch12.o.uu b/gdb/testsuite/gdb.arch/s390x-arch12.o.uu
+new file mode 100644
+index 0000000000..2cee883b0f
+--- /dev/null
++++ b/gdb/testsuite/gdb.arch/s390x-arch12.o.uu
+@@ -0,0 +1,20 @@
++begin 644 s390x-arch12.o
++M?T5,1@("`0`````````````!`!8````!````````````````````````````
++M``$X``````!```````!```<`!.N_\%@`)./P_U#_<;D$`+_C(+"@`"3C$+"@
++M``3C$!```$SC$+"H`"3C$+"H``2Y!``AXT"Q(``$Z[^Q"``$!_0`+G-Y;71A
++M8@`N<W1R=&%B`"YS:'-T<G1A8@`N=&5X=``N9&%T80`N8G-S````````````
++M`````````````````````````````````P```0``````````````````````
++M`````P```@```````````````````````````P```P``````````````````
++M```````!$````0``````````````````````;&]A9%]G=6%R9&5D````````
++M````````````````````````````````````````````````````````````
++M`````````````````````````!L````!``````````8`````````````````
++M``!``````````$`````````````````````$```````````````A`````0``
++M```````#````````````````````@```````````````````````````````
++M!```````````````)P````@``````````P```````````````````(``````
++M``````````````````````````0``````````````!$````#````````````
++M``````````````````"``````````"P````````````````````!````````
++M```````!`````@``````````````````````````````L`````````!X````
++M!@````0`````````"``````````8````"0````,`````````````````````
++H`````````2@`````````#@````````````````````$`````````````
++`
++end
+-- 
+2.14.3
+
diff --git a/gdb.spec b/gdb.spec
index b63f3fc..d19c2ad 100644
--- a/gdb.spec
+++ b/gdb.spec
@@ -26,7 +26,7 @@ Version: 8.1
 
 # The release always contains a leading reserved number, start it at 1.
 # `upstream' is not a part of `name' to stay fully rpm dependencies compatible for the testing.
-Release: 11%{?dist}
+Release: 12%{?dist}
 
 License: GPLv3+ and GPLv3+ with exceptions and GPLv2+ and GPLv2+ with exceptions and GPL+ and LGPLv2+ and LGPLv3+ and BSD and Public Domain and GFDL
 Group: Development/Debuggers
@@ -1026,6 +1026,9 @@ then
 fi
 
 %changelog
+* Fri Mar 23 2018 Jan Kratochvil <jan.kratochvil@redhat.com> - 8.1-12.fc28
+- Add test: [s390x] Backport arch12 instructions decoding (RH BZ 1553104).
+
 * Sat Mar  3 2018 Jan Kratochvil <jan.kratochvil@redhat.com> - 8.1-11.fc28
 - Add: BuildRequires: gcc-c++
   https://fedoraproject.org/wiki/Packaging:C_and_C%2B%2B#BuildRequires_and_Requires