diff -Nru valgrind-3.15.0/debian/changelog valgrind-3.15.0/debian/changelog
--- valgrind-3.15.0/debian/changelog	2020-04-03 05:34:19.000000000 -0500
+++ valgrind-3.15.0/debian/changelog	2020-08-20 11:50:58.000000000 -0500
@@ -1,3 +1,9 @@
+valgrind (1:3.15.0-1ubuntu9.1) focal; urgency=medium
+
+  * The L field is currently a two bit[22:21] field in ISA 3.0. (LP: #1887974)
+
+ -- Matthieu Clemenceau <matthieu.clemenceau@canonical.com>  Thu, 20 Aug 2020 11:50:58 -0500
+
 valgrind (1:3.15.0-1ubuntu9) focal; urgency=medium
 
   * Prevent valgrind trying to use unrecognised z14/z15 instructions. LP:
diff -Nru valgrind-3.15.0/debian/patches/ppc-lfield-two-bits-ISA30.diff valgrind-3.15.0/debian/patches/ppc-lfield-two-bits-ISA30.diff
--- valgrind-3.15.0/debian/patches/ppc-lfield-two-bits-ISA30.diff	1969-12-31 18:00:00.000000000 -0600
+++ valgrind-3.15.0/debian/patches/ppc-lfield-two-bits-ISA30.diff	2020-08-20 11:49:47.000000000 -0500
@@ -0,0 +1,27 @@
+commit fb6f7abcbc92506d302fb18a2c5fc853d2929248
+Author: Carl Love <cel@us.ibm.com>
+Date:   Tue Jun 9 10:42:03 2020 -0500
+
+    Power PC Fix extraction of the L field for sync instruction
+    
+    The L field is currently a two bit[22:21] field in ISA 3.0. The size of the
+    L field has changed over time.
+    
+    Currently the ISA 3.0 Valgrind sync instruction support code sets the
+    flag_L for the instruction L field to a five bit value that includes bits
+    that are marked reserved the sync instruction.  This patch fixes the issue for ISA 3.0
+    to only setting flag_L the specified two bits.
+    
+    Valgrind bugzilla:   https://bugs.kde.org/show_bug.cgi?id=422677
+
+--- a/VEX/priv/guest_ppc_toIR.c
++++ b/VEX/priv/guest_ppc_toIR.c
+@@ -8537,7 +8537,7 @@
+    /* X-Form, XL-Form */
+    UChar opc1    = ifieldOPC(theInstr);
+    UInt  b11to25 = IFIELD(theInstr, 11, 15);
+-   UChar flag_L  = ifieldRegDS(theInstr);
++   UChar flag_L  = IFIELD(theInstr, 21, 2);   //ISA 3.0
+    UInt  b11to20 = IFIELD(theInstr, 11, 10);
+    UInt  M0      = IFIELD(theInstr, 11, 5);
+    UChar rD_addr = ifieldRegDS(theInstr);
diff -Nru valgrind-3.15.0/debian/patches/series valgrind-3.15.0/debian/patches/series
--- valgrind-3.15.0/debian/patches/series	2020-04-03 05:34:13.000000000 -0500
+++ valgrind-3.15.0/debian/patches/series	2020-08-20 11:42:44.000000000 -0500
@@ -12,3 +12,4 @@
 drop-MPI-1-support.patch
 0001-Bug-416301-s390x-Support-compare-and-signal-instruct.patch
 0001-s390x-Unset-facility-bits-for-unsupported-z14-z15-fa.patch
+ppc-lfield-two-bits-ISA30.diff