diff --git a/tests/xfs/1842 b/tests/xfs/1842
new file mode 100755
index 0000000000..8180ca7a6e
--- /dev/null
+++ b/tests/xfs/1842
@@ -0,0 +1,55 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2022-2024 Oracle.  All Rights Reserved.
+#
+# FS QA Test No. 1842
+#
+# mkfs concurrency test - ensure the log and agsize scaling works for various
+# concurrency= parameters
+#
+. ./common/preamble
+_begin_fstest log metadata auto quick
+
+# Import common functions.
+. ./common/filter
+. ./common/reflink
+
+_cleanup()
+{
+	cd /
+	rm -r -f $tmp.* $loop_file
+}
+
+# real QA test starts here
+_supported_fs xfs
+
+_require_test
+_require_loop
+$MKFS_XFS_PROG 2>&1 | grep -q concurrency || \
+	_notrun "mkfs does not support concurrency options"
+
+test_dev_lbasize=$(blockdev --getss $TEST_DEV)
+seqfull=$0
+_link_out_file "lba${test_dev_lbasize}"
+
+loop_file=$TEST_DIR/$seq.loop
+
+rm -f "$loop_file"
+for sz in 16M 512M 1G 2G 16G 64G 256G 512G 1T 2T 4T 16T 64T 256T 512T 1P; do
+	for cpus in 2 4 8 16 32 40 64 96 160 512; do
+		truncate -s "$sz" "$loop_file"
+		echo "sz $sz cpus $cpus" >> $seqres.full
+		echo "-----------------" >> $seqres.full
+
+		$MKFS_XFS_PROG -f -N "$loop_file" -d concurrency=$cpus -l concurrency=$cpus &> $tmp.mkfsout
+		cat $tmp.mkfsout >> $seqres.full
+
+		_filter_mkfs > /dev/null 2> $tmp.mkfs < $tmp.mkfsout
+		. $tmp.mkfs
+		echo "sz $sz cpus $cpus agcount $agcount logblocks $lblocks"
+	done
+	echo "-----------------"
+done
+
+status=0
+exit
diff --git a/tests/xfs/1842.cfg b/tests/xfs/1842.cfg
new file mode 100644
index 0000000000..0678032432
--- /dev/null
+++ b/tests/xfs/1842.cfg
@@ -0,0 +1,4 @@
+lba512: lba512
+lba1024: lba1024
+lba2048: lba2048
+lba4096: lba4096
diff --git a/tests/xfs/1842.out.lba1024 b/tests/xfs/1842.out.lba1024
new file mode 100644
index 0000000000..758cdf51a8
--- /dev/null
+++ b/tests/xfs/1842.out.lba1024
@@ -0,0 +1,177 @@
+QA output created by 1842
+sz 16M cpus 2 agcount 1 logblocks 2766
+sz 16M cpus 4 agcount 1 logblocks 2766
+sz 16M cpus 8 agcount 1 logblocks 2766
+sz 16M cpus 16 agcount 1 logblocks 2766
+sz 16M cpus 32 agcount 1 logblocks 2766
+sz 16M cpus 40 agcount 1 logblocks 2766
+sz 16M cpus 64 agcount 1 logblocks 2766
+sz 16M cpus 96 agcount 1 logblocks 2766
+sz 16M cpus 160 agcount 1 logblocks 2766
+sz 16M cpus 512 agcount 1 logblocks 2766
+-----------------
+sz 512M cpus 2 agcount 4 logblocks 16384
+sz 512M cpus 4 agcount 4 logblocks 16384
+sz 512M cpus 8 agcount 4 logblocks 16384
+sz 512M cpus 16 agcount 4 logblocks 16384
+sz 512M cpus 32 agcount 4 logblocks 16384
+sz 512M cpus 40 agcount 4 logblocks 16384
+sz 512M cpus 64 agcount 4 logblocks 16384
+sz 512M cpus 96 agcount 4 logblocks 16384
+sz 512M cpus 160 agcount 4 logblocks 16384
+sz 512M cpus 512 agcount 4 logblocks 16384
+-----------------
+sz 1G cpus 2 agcount 4 logblocks 16384
+sz 1G cpus 4 agcount 4 logblocks 16384
+sz 1G cpus 8 agcount 4 logblocks 16384
+sz 1G cpus 16 agcount 4 logblocks 22698
+sz 1G cpus 32 agcount 4 logblocks 45396
+sz 1G cpus 40 agcount 4 logblocks 56745
+sz 1G cpus 64 agcount 4 logblocks 65524
+sz 1G cpus 96 agcount 4 logblocks 65524
+sz 1G cpus 160 agcount 4 logblocks 65524
+sz 1G cpus 512 agcount 4 logblocks 65524
+-----------------
+sz 2G cpus 2 agcount 4 logblocks 16384
+sz 2G cpus 4 agcount 4 logblocks 16384
+sz 2G cpus 8 agcount 4 logblocks 16384
+sz 2G cpus 16 agcount 4 logblocks 25866
+sz 2G cpus 32 agcount 4 logblocks 51732
+sz 2G cpus 40 agcount 4 logblocks 64665
+sz 2G cpus 64 agcount 4 logblocks 103464
+sz 2G cpus 96 agcount 4 logblocks 131060
+sz 2G cpus 160 agcount 4 logblocks 131060
+sz 2G cpus 512 agcount 4 logblocks 131060
+-----------------
+sz 16G cpus 2 agcount 4 logblocks 16384
+sz 16G cpus 4 agcount 4 logblocks 16384
+sz 16G cpus 8 agcount 4 logblocks 16384
+sz 16G cpus 16 agcount 4 logblocks 25866
+sz 16G cpus 32 agcount 4 logblocks 51732
+sz 16G cpus 40 agcount 4 logblocks 64665
+sz 16G cpus 64 agcount 4 logblocks 103464
+sz 16G cpus 96 agcount 4 logblocks 155196
+sz 16G cpus 160 agcount 4 logblocks 258660
+sz 16G cpus 512 agcount 4 logblocks 521728
+-----------------
+sz 64G cpus 2 agcount 4 logblocks 16384
+sz 64G cpus 4 agcount 4 logblocks 16384
+sz 64G cpus 8 agcount 8 logblocks 16384
+sz 64G cpus 16 agcount 16 logblocks 25866
+sz 64G cpus 32 agcount 16 logblocks 51732
+sz 64G cpus 40 agcount 16 logblocks 64665
+sz 64G cpus 64 agcount 16 logblocks 103464
+sz 64G cpus 96 agcount 16 logblocks 155196
+sz 64G cpus 160 agcount 16 logblocks 258660
+sz 64G cpus 512 agcount 16 logblocks 521728
+-----------------
+sz 256G cpus 2 agcount 4 logblocks 32768
+sz 256G cpus 4 agcount 4 logblocks 32768
+sz 256G cpus 8 agcount 8 logblocks 32768
+sz 256G cpus 16 agcount 16 logblocks 32768
+sz 256G cpus 32 agcount 32 logblocks 51732
+sz 256G cpus 40 agcount 40 logblocks 64665
+sz 256G cpus 64 agcount 64 logblocks 103464
+sz 256G cpus 96 agcount 64 logblocks 155196
+sz 256G cpus 160 agcount 64 logblocks 258660
+sz 256G cpus 512 agcount 64 logblocks 521728
+-----------------
+sz 512G cpus 2 agcount 4 logblocks 65536
+sz 512G cpus 4 agcount 4 logblocks 65536
+sz 512G cpus 8 agcount 8 logblocks 65536
+sz 512G cpus 16 agcount 16 logblocks 65536
+sz 512G cpus 32 agcount 32 logblocks 65536
+sz 512G cpus 40 agcount 40 logblocks 65535
+sz 512G cpus 64 agcount 64 logblocks 103464
+sz 512G cpus 96 agcount 96 logblocks 155196
+sz 512G cpus 160 agcount 128 logblocks 258660
+sz 512G cpus 512 agcount 128 logblocks 521728
+-----------------
+sz 1T cpus 2 agcount 4 logblocks 131072
+sz 1T cpus 4 agcount 4 logblocks 131072
+sz 1T cpus 8 agcount 8 logblocks 131072
+sz 1T cpus 16 agcount 16 logblocks 131072
+sz 1T cpus 32 agcount 32 logblocks 131072
+sz 1T cpus 40 agcount 40 logblocks 131071
+sz 1T cpus 64 agcount 64 logblocks 131072
+sz 1T cpus 96 agcount 96 logblocks 155196
+sz 1T cpus 160 agcount 160 logblocks 258660
+sz 1T cpus 512 agcount 256 logblocks 521728
+-----------------
+sz 2T cpus 2 agcount 4 logblocks 262144
+sz 2T cpus 4 agcount 4 logblocks 262144
+sz 2T cpus 8 agcount 8 logblocks 262144
+sz 2T cpus 16 agcount 16 logblocks 262144
+sz 2T cpus 32 agcount 32 logblocks 262144
+sz 2T cpus 40 agcount 40 logblocks 262143
+sz 2T cpus 64 agcount 64 logblocks 262144
+sz 2T cpus 96 agcount 96 logblocks 262143
+sz 2T cpus 160 agcount 160 logblocks 262143
+sz 2T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 4T cpus 2 agcount 4 logblocks 521728
+sz 4T cpus 4 agcount 4 logblocks 521728
+sz 4T cpus 8 agcount 8 logblocks 521728
+sz 4T cpus 16 agcount 16 logblocks 521728
+sz 4T cpus 32 agcount 32 logblocks 521728
+sz 4T cpus 40 agcount 40 logblocks 521728
+sz 4T cpus 64 agcount 64 logblocks 521728
+sz 4T cpus 96 agcount 96 logblocks 521728
+sz 4T cpus 160 agcount 160 logblocks 521728
+sz 4T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 16T cpus 2 agcount 16 logblocks 521728
+sz 16T cpus 4 agcount 16 logblocks 521728
+sz 16T cpus 8 agcount 16 logblocks 521728
+sz 16T cpus 16 agcount 16 logblocks 521728
+sz 16T cpus 32 agcount 32 logblocks 521728
+sz 16T cpus 40 agcount 40 logblocks 521728
+sz 16T cpus 64 agcount 64 logblocks 521728
+sz 16T cpus 96 agcount 96 logblocks 521728
+sz 16T cpus 160 agcount 160 logblocks 521728
+sz 16T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 64T cpus 2 agcount 64 logblocks 521728
+sz 64T cpus 4 agcount 64 logblocks 521728
+sz 64T cpus 8 agcount 64 logblocks 521728
+sz 64T cpus 16 agcount 64 logblocks 521728
+sz 64T cpus 32 agcount 64 logblocks 521728
+sz 64T cpus 40 agcount 64 logblocks 521728
+sz 64T cpus 64 agcount 64 logblocks 521728
+sz 64T cpus 96 agcount 96 logblocks 521728
+sz 64T cpus 160 agcount 160 logblocks 521728
+sz 64T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 256T cpus 2 agcount 256 logblocks 521728
+sz 256T cpus 4 agcount 256 logblocks 521728
+sz 256T cpus 8 agcount 256 logblocks 521728
+sz 256T cpus 16 agcount 256 logblocks 521728
+sz 256T cpus 32 agcount 256 logblocks 521728
+sz 256T cpus 40 agcount 256 logblocks 521728
+sz 256T cpus 64 agcount 256 logblocks 521728
+sz 256T cpus 96 agcount 256 logblocks 521728
+sz 256T cpus 160 agcount 256 logblocks 521728
+sz 256T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 512T cpus 2 agcount 512 logblocks 521728
+sz 512T cpus 4 agcount 512 logblocks 521728
+sz 512T cpus 8 agcount 512 logblocks 521728
+sz 512T cpus 16 agcount 512 logblocks 521728
+sz 512T cpus 32 agcount 512 logblocks 521728
+sz 512T cpus 40 agcount 512 logblocks 521728
+sz 512T cpus 64 agcount 512 logblocks 521728
+sz 512T cpus 96 agcount 512 logblocks 521728
+sz 512T cpus 160 agcount 512 logblocks 521728
+sz 512T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 1P cpus 2 agcount 1024 logblocks 521728
+sz 1P cpus 4 agcount 1024 logblocks 521728
+sz 1P cpus 8 agcount 1024 logblocks 521728
+sz 1P cpus 16 agcount 1024 logblocks 521728
+sz 1P cpus 32 agcount 1024 logblocks 521728
+sz 1P cpus 40 agcount 1024 logblocks 521728
+sz 1P cpus 64 agcount 1024 logblocks 521728
+sz 1P cpus 96 agcount 1024 logblocks 521728
+sz 1P cpus 160 agcount 1024 logblocks 521728
+sz 1P cpus 512 agcount 1024 logblocks 521728
+-----------------
diff --git a/tests/xfs/1842.out.lba2048 b/tests/xfs/1842.out.lba2048
new file mode 100644
index 0000000000..5ec8e640c8
--- /dev/null
+++ b/tests/xfs/1842.out.lba2048
@@ -0,0 +1,177 @@
+QA output created by 1842
+sz 16M cpus 2 agcount 1 logblocks 2820
+sz 16M cpus 4 agcount 1 logblocks 2820
+sz 16M cpus 8 agcount 1 logblocks 2820
+sz 16M cpus 16 agcount 1 logblocks 2820
+sz 16M cpus 32 agcount 1 logblocks 2820
+sz 16M cpus 40 agcount 1 logblocks 2820
+sz 16M cpus 64 agcount 1 logblocks 2820
+sz 16M cpus 96 agcount 1 logblocks 2820
+sz 16M cpus 160 agcount 1 logblocks 2820
+sz 16M cpus 512 agcount 1 logblocks 2820
+-----------------
+sz 512M cpus 2 agcount 4 logblocks 16384
+sz 512M cpus 4 agcount 4 logblocks 16384
+sz 512M cpus 8 agcount 4 logblocks 16384
+sz 512M cpus 16 agcount 4 logblocks 16384
+sz 512M cpus 32 agcount 4 logblocks 16384
+sz 512M cpus 40 agcount 4 logblocks 16384
+sz 512M cpus 64 agcount 4 logblocks 16384
+sz 512M cpus 96 agcount 4 logblocks 16384
+sz 512M cpus 160 agcount 4 logblocks 16384
+sz 512M cpus 512 agcount 4 logblocks 16384
+-----------------
+sz 1G cpus 2 agcount 4 logblocks 16384
+sz 1G cpus 4 agcount 4 logblocks 16384
+sz 1G cpus 8 agcount 4 logblocks 16384
+sz 1G cpus 16 agcount 4 logblocks 23130
+sz 1G cpus 32 agcount 4 logblocks 46260
+sz 1G cpus 40 agcount 4 logblocks 57825
+sz 1G cpus 64 agcount 4 logblocks 65523
+sz 1G cpus 96 agcount 4 logblocks 65523
+sz 1G cpus 160 agcount 4 logblocks 65523
+sz 1G cpus 512 agcount 4 logblocks 65523
+-----------------
+sz 2G cpus 2 agcount 4 logblocks 16384
+sz 2G cpus 4 agcount 4 logblocks 16384
+sz 2G cpus 8 agcount 4 logblocks 16384
+sz 2G cpus 16 agcount 4 logblocks 26298
+sz 2G cpus 32 agcount 4 logblocks 52596
+sz 2G cpus 40 agcount 4 logblocks 65745
+sz 2G cpus 64 agcount 4 logblocks 105192
+sz 2G cpus 96 agcount 4 logblocks 131059
+sz 2G cpus 160 agcount 4 logblocks 131059
+sz 2G cpus 512 agcount 4 logblocks 131059
+-----------------
+sz 16G cpus 2 agcount 4 logblocks 16384
+sz 16G cpus 4 agcount 4 logblocks 16384
+sz 16G cpus 8 agcount 4 logblocks 16384
+sz 16G cpus 16 agcount 4 logblocks 26298
+sz 16G cpus 32 agcount 4 logblocks 52596
+sz 16G cpus 40 agcount 4 logblocks 65745
+sz 16G cpus 64 agcount 4 logblocks 105192
+sz 16G cpus 96 agcount 4 logblocks 157788
+sz 16G cpus 160 agcount 4 logblocks 262980
+sz 16G cpus 512 agcount 4 logblocks 521728
+-----------------
+sz 64G cpus 2 agcount 4 logblocks 16384
+sz 64G cpus 4 agcount 4 logblocks 16384
+sz 64G cpus 8 agcount 8 logblocks 16384
+sz 64G cpus 16 agcount 16 logblocks 26298
+sz 64G cpus 32 agcount 16 logblocks 52596
+sz 64G cpus 40 agcount 16 logblocks 65745
+sz 64G cpus 64 agcount 16 logblocks 105192
+sz 64G cpus 96 agcount 16 logblocks 157788
+sz 64G cpus 160 agcount 16 logblocks 262980
+sz 64G cpus 512 agcount 16 logblocks 521728
+-----------------
+sz 256G cpus 2 agcount 4 logblocks 32768
+sz 256G cpus 4 agcount 4 logblocks 32768
+sz 256G cpus 8 agcount 8 logblocks 32768
+sz 256G cpus 16 agcount 16 logblocks 32768
+sz 256G cpus 32 agcount 32 logblocks 52596
+sz 256G cpus 40 agcount 40 logblocks 65745
+sz 256G cpus 64 agcount 64 logblocks 105192
+sz 256G cpus 96 agcount 64 logblocks 157788
+sz 256G cpus 160 agcount 64 logblocks 262980
+sz 256G cpus 512 agcount 64 logblocks 521728
+-----------------
+sz 512G cpus 2 agcount 4 logblocks 65536
+sz 512G cpus 4 agcount 4 logblocks 65536
+sz 512G cpus 8 agcount 8 logblocks 65536
+sz 512G cpus 16 agcount 16 logblocks 65536
+sz 512G cpus 32 agcount 32 logblocks 65536
+sz 512G cpus 40 agcount 40 logblocks 65745
+sz 512G cpus 64 agcount 64 logblocks 105192
+sz 512G cpus 96 agcount 96 logblocks 157788
+sz 512G cpus 160 agcount 128 logblocks 262980
+sz 512G cpus 512 agcount 128 logblocks 521728
+-----------------
+sz 1T cpus 2 agcount 4 logblocks 131072
+sz 1T cpus 4 agcount 4 logblocks 131072
+sz 1T cpus 8 agcount 8 logblocks 131072
+sz 1T cpus 16 agcount 16 logblocks 131072
+sz 1T cpus 32 agcount 32 logblocks 131072
+sz 1T cpus 40 agcount 40 logblocks 131071
+sz 1T cpus 64 agcount 64 logblocks 131072
+sz 1T cpus 96 agcount 96 logblocks 157788
+sz 1T cpus 160 agcount 160 logblocks 262980
+sz 1T cpus 512 agcount 256 logblocks 521728
+-----------------
+sz 2T cpus 2 agcount 4 logblocks 262144
+sz 2T cpus 4 agcount 4 logblocks 262144
+sz 2T cpus 8 agcount 8 logblocks 262144
+sz 2T cpus 16 agcount 16 logblocks 262144
+sz 2T cpus 32 agcount 32 logblocks 262144
+sz 2T cpus 40 agcount 40 logblocks 262143
+sz 2T cpus 64 agcount 64 logblocks 262144
+sz 2T cpus 96 agcount 96 logblocks 262143
+sz 2T cpus 160 agcount 160 logblocks 262980
+sz 2T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 4T cpus 2 agcount 4 logblocks 521728
+sz 4T cpus 4 agcount 4 logblocks 521728
+sz 4T cpus 8 agcount 8 logblocks 521728
+sz 4T cpus 16 agcount 16 logblocks 521728
+sz 4T cpus 32 agcount 32 logblocks 521728
+sz 4T cpus 40 agcount 40 logblocks 521728
+sz 4T cpus 64 agcount 64 logblocks 521728
+sz 4T cpus 96 agcount 96 logblocks 521728
+sz 4T cpus 160 agcount 160 logblocks 521728
+sz 4T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 16T cpus 2 agcount 16 logblocks 521728
+sz 16T cpus 4 agcount 16 logblocks 521728
+sz 16T cpus 8 agcount 16 logblocks 521728
+sz 16T cpus 16 agcount 16 logblocks 521728
+sz 16T cpus 32 agcount 32 logblocks 521728
+sz 16T cpus 40 agcount 40 logblocks 521728
+sz 16T cpus 64 agcount 64 logblocks 521728
+sz 16T cpus 96 agcount 96 logblocks 521728
+sz 16T cpus 160 agcount 160 logblocks 521728
+sz 16T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 64T cpus 2 agcount 64 logblocks 521728
+sz 64T cpus 4 agcount 64 logblocks 521728
+sz 64T cpus 8 agcount 64 logblocks 521728
+sz 64T cpus 16 agcount 64 logblocks 521728
+sz 64T cpus 32 agcount 64 logblocks 521728
+sz 64T cpus 40 agcount 64 logblocks 521728
+sz 64T cpus 64 agcount 64 logblocks 521728
+sz 64T cpus 96 agcount 96 logblocks 521728
+sz 64T cpus 160 agcount 160 logblocks 521728
+sz 64T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 256T cpus 2 agcount 256 logblocks 521728
+sz 256T cpus 4 agcount 256 logblocks 521728
+sz 256T cpus 8 agcount 256 logblocks 521728
+sz 256T cpus 16 agcount 256 logblocks 521728
+sz 256T cpus 32 agcount 256 logblocks 521728
+sz 256T cpus 40 agcount 256 logblocks 521728
+sz 256T cpus 64 agcount 256 logblocks 521728
+sz 256T cpus 96 agcount 256 logblocks 521728
+sz 256T cpus 160 agcount 256 logblocks 521728
+sz 256T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 512T cpus 2 agcount 512 logblocks 521728
+sz 512T cpus 4 agcount 512 logblocks 521728
+sz 512T cpus 8 agcount 512 logblocks 521728
+sz 512T cpus 16 agcount 512 logblocks 521728
+sz 512T cpus 32 agcount 512 logblocks 521728
+sz 512T cpus 40 agcount 512 logblocks 521728
+sz 512T cpus 64 agcount 512 logblocks 521728
+sz 512T cpus 96 agcount 512 logblocks 521728
+sz 512T cpus 160 agcount 512 logblocks 521728
+sz 512T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 1P cpus 2 agcount 1024 logblocks 521728
+sz 1P cpus 4 agcount 1024 logblocks 521728
+sz 1P cpus 8 agcount 1024 logblocks 521728
+sz 1P cpus 16 agcount 1024 logblocks 521728
+sz 1P cpus 32 agcount 1024 logblocks 521728
+sz 1P cpus 40 agcount 1024 logblocks 521728
+sz 1P cpus 64 agcount 1024 logblocks 521728
+sz 1P cpus 96 agcount 1024 logblocks 521728
+sz 1P cpus 160 agcount 1024 logblocks 521728
+sz 1P cpus 512 agcount 1024 logblocks 521728
+-----------------
diff --git a/tests/xfs/1842.out.lba4096 b/tests/xfs/1842.out.lba4096
new file mode 100644
index 0000000000..6f5376f508
--- /dev/null
+++ b/tests/xfs/1842.out.lba4096
@@ -0,0 +1,177 @@
+QA output created by 1842
+sz 16M cpus 2 agcount 1 logblocks 2928
+sz 16M cpus 4 agcount 1 logblocks 2928
+sz 16M cpus 8 agcount 1 logblocks 2928
+sz 16M cpus 16 agcount 1 logblocks 2928
+sz 16M cpus 32 agcount 1 logblocks 2928
+sz 16M cpus 40 agcount 1 logblocks 2928
+sz 16M cpus 64 agcount 1 logblocks 2928
+sz 16M cpus 96 agcount 1 logblocks 2928
+sz 16M cpus 160 agcount 1 logblocks 2928
+sz 16M cpus 512 agcount 1 logblocks 2928
+-----------------
+sz 512M cpus 2 agcount 4 logblocks 16384
+sz 512M cpus 4 agcount 4 logblocks 16384
+sz 512M cpus 8 agcount 4 logblocks 16384
+sz 512M cpus 16 agcount 4 logblocks 16384
+sz 512M cpus 32 agcount 4 logblocks 16384
+sz 512M cpus 40 agcount 4 logblocks 16384
+sz 512M cpus 64 agcount 4 logblocks 16384
+sz 512M cpus 96 agcount 4 logblocks 16384
+sz 512M cpus 160 agcount 4 logblocks 16384
+sz 512M cpus 512 agcount 4 logblocks 16384
+-----------------
+sz 1G cpus 2 agcount 4 logblocks 16384
+sz 1G cpus 4 agcount 4 logblocks 16384
+sz 1G cpus 8 agcount 4 logblocks 16384
+sz 1G cpus 16 agcount 4 logblocks 23994
+sz 1G cpus 32 agcount 4 logblocks 47988
+sz 1G cpus 40 agcount 4 logblocks 59985
+sz 1G cpus 64 agcount 4 logblocks 65521
+sz 1G cpus 96 agcount 4 logblocks 65521
+sz 1G cpus 160 agcount 4 logblocks 65521
+sz 1G cpus 512 agcount 4 logblocks 65521
+-----------------
+sz 2G cpus 2 agcount 4 logblocks 16384
+sz 2G cpus 4 agcount 4 logblocks 16384
+sz 2G cpus 8 agcount 4 logblocks 16384
+sz 2G cpus 16 agcount 4 logblocks 27162
+sz 2G cpus 32 agcount 4 logblocks 54324
+sz 2G cpus 40 agcount 4 logblocks 67905
+sz 2G cpus 64 agcount 4 logblocks 108648
+sz 2G cpus 96 agcount 4 logblocks 131057
+sz 2G cpus 160 agcount 4 logblocks 131057
+sz 2G cpus 512 agcount 4 logblocks 131057
+-----------------
+sz 16G cpus 2 agcount 4 logblocks 16384
+sz 16G cpus 4 agcount 4 logblocks 16384
+sz 16G cpus 8 agcount 4 logblocks 16384
+sz 16G cpus 16 agcount 4 logblocks 27162
+sz 16G cpus 32 agcount 4 logblocks 54324
+sz 16G cpus 40 agcount 4 logblocks 67905
+sz 16G cpus 64 agcount 4 logblocks 108648
+sz 16G cpus 96 agcount 4 logblocks 162972
+sz 16G cpus 160 agcount 4 logblocks 271620
+sz 16G cpus 512 agcount 4 logblocks 521728
+-----------------
+sz 64G cpus 2 agcount 4 logblocks 16384
+sz 64G cpus 4 agcount 4 logblocks 16384
+sz 64G cpus 8 agcount 8 logblocks 16384
+sz 64G cpus 16 agcount 16 logblocks 27162
+sz 64G cpus 32 agcount 16 logblocks 54324
+sz 64G cpus 40 agcount 16 logblocks 67905
+sz 64G cpus 64 agcount 16 logblocks 108648
+sz 64G cpus 96 agcount 16 logblocks 162972
+sz 64G cpus 160 agcount 16 logblocks 271620
+sz 64G cpus 512 agcount 16 logblocks 521728
+-----------------
+sz 256G cpus 2 agcount 4 logblocks 32768
+sz 256G cpus 4 agcount 4 logblocks 32768
+sz 256G cpus 8 agcount 8 logblocks 32768
+sz 256G cpus 16 agcount 16 logblocks 32768
+sz 256G cpus 32 agcount 32 logblocks 54324
+sz 256G cpus 40 agcount 40 logblocks 67905
+sz 256G cpus 64 agcount 64 logblocks 108648
+sz 256G cpus 96 agcount 64 logblocks 162972
+sz 256G cpus 160 agcount 64 logblocks 271620
+sz 256G cpus 512 agcount 64 logblocks 521728
+-----------------
+sz 512G cpus 2 agcount 4 logblocks 65536
+sz 512G cpus 4 agcount 4 logblocks 65536
+sz 512G cpus 8 agcount 8 logblocks 65536
+sz 512G cpus 16 agcount 16 logblocks 65536
+sz 512G cpus 32 agcount 32 logblocks 65536
+sz 512G cpus 40 agcount 40 logblocks 67905
+sz 512G cpus 64 agcount 64 logblocks 108648
+sz 512G cpus 96 agcount 96 logblocks 162972
+sz 512G cpus 160 agcount 128 logblocks 271620
+sz 512G cpus 512 agcount 128 logblocks 521728
+-----------------
+sz 1T cpus 2 agcount 4 logblocks 131072
+sz 1T cpus 4 agcount 4 logblocks 131072
+sz 1T cpus 8 agcount 8 logblocks 131072
+sz 1T cpus 16 agcount 16 logblocks 131072
+sz 1T cpus 32 agcount 32 logblocks 131072
+sz 1T cpus 40 agcount 40 logblocks 131071
+sz 1T cpus 64 agcount 64 logblocks 131072
+sz 1T cpus 96 agcount 96 logblocks 162972
+sz 1T cpus 160 agcount 160 logblocks 271620
+sz 1T cpus 512 agcount 256 logblocks 521728
+-----------------
+sz 2T cpus 2 agcount 4 logblocks 262144
+sz 2T cpus 4 agcount 4 logblocks 262144
+sz 2T cpus 8 agcount 8 logblocks 262144
+sz 2T cpus 16 agcount 16 logblocks 262144
+sz 2T cpus 32 agcount 32 logblocks 262144
+sz 2T cpus 40 agcount 40 logblocks 262143
+sz 2T cpus 64 agcount 64 logblocks 262144
+sz 2T cpus 96 agcount 96 logblocks 262143
+sz 2T cpus 160 agcount 160 logblocks 271620
+sz 2T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 4T cpus 2 agcount 4 logblocks 521728
+sz 4T cpus 4 agcount 4 logblocks 521728
+sz 4T cpus 8 agcount 8 logblocks 521728
+sz 4T cpus 16 agcount 16 logblocks 521728
+sz 4T cpus 32 agcount 32 logblocks 521728
+sz 4T cpus 40 agcount 40 logblocks 521728
+sz 4T cpus 64 agcount 64 logblocks 521728
+sz 4T cpus 96 agcount 96 logblocks 521728
+sz 4T cpus 160 agcount 160 logblocks 521728
+sz 4T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 16T cpus 2 agcount 16 logblocks 521728
+sz 16T cpus 4 agcount 16 logblocks 521728
+sz 16T cpus 8 agcount 16 logblocks 521728
+sz 16T cpus 16 agcount 16 logblocks 521728
+sz 16T cpus 32 agcount 32 logblocks 521728
+sz 16T cpus 40 agcount 40 logblocks 521728
+sz 16T cpus 64 agcount 64 logblocks 521728
+sz 16T cpus 96 agcount 96 logblocks 521728
+sz 16T cpus 160 agcount 160 logblocks 521728
+sz 16T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 64T cpus 2 agcount 64 logblocks 521728
+sz 64T cpus 4 agcount 64 logblocks 521728
+sz 64T cpus 8 agcount 64 logblocks 521728
+sz 64T cpus 16 agcount 64 logblocks 521728
+sz 64T cpus 32 agcount 64 logblocks 521728
+sz 64T cpus 40 agcount 64 logblocks 521728
+sz 64T cpus 64 agcount 64 logblocks 521728
+sz 64T cpus 96 agcount 96 logblocks 521728
+sz 64T cpus 160 agcount 160 logblocks 521728
+sz 64T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 256T cpus 2 agcount 256 logblocks 521728
+sz 256T cpus 4 agcount 256 logblocks 521728
+sz 256T cpus 8 agcount 256 logblocks 521728
+sz 256T cpus 16 agcount 256 logblocks 521728
+sz 256T cpus 32 agcount 256 logblocks 521728
+sz 256T cpus 40 agcount 256 logblocks 521728
+sz 256T cpus 64 agcount 256 logblocks 521728
+sz 256T cpus 96 agcount 256 logblocks 521728
+sz 256T cpus 160 agcount 256 logblocks 521728
+sz 256T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 512T cpus 2 agcount 512 logblocks 521728
+sz 512T cpus 4 agcount 512 logblocks 521728
+sz 512T cpus 8 agcount 512 logblocks 521728
+sz 512T cpus 16 agcount 512 logblocks 521728
+sz 512T cpus 32 agcount 512 logblocks 521728
+sz 512T cpus 40 agcount 512 logblocks 521728
+sz 512T cpus 64 agcount 512 logblocks 521728
+sz 512T cpus 96 agcount 512 logblocks 521728
+sz 512T cpus 160 agcount 512 logblocks 521728
+sz 512T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 1P cpus 2 agcount 1024 logblocks 521728
+sz 1P cpus 4 agcount 1024 logblocks 521728
+sz 1P cpus 8 agcount 1024 logblocks 521728
+sz 1P cpus 16 agcount 1024 logblocks 521728
+sz 1P cpus 32 agcount 1024 logblocks 521728
+sz 1P cpus 40 agcount 1024 logblocks 521728
+sz 1P cpus 64 agcount 1024 logblocks 521728
+sz 1P cpus 96 agcount 1024 logblocks 521728
+sz 1P cpus 160 agcount 1024 logblocks 521728
+sz 1P cpus 512 agcount 1024 logblocks 521728
+-----------------
diff --git a/tests/xfs/1842.out.lba512 b/tests/xfs/1842.out.lba512
new file mode 100644
index 0000000000..e28742e8ae
--- /dev/null
+++ b/tests/xfs/1842.out.lba512
@@ -0,0 +1,177 @@
+QA output created by 1842
+sz 16M cpus 2 agcount 1 logblocks 3075
+sz 16M cpus 4 agcount 1 logblocks 3075
+sz 16M cpus 8 agcount 1 logblocks 3075
+sz 16M cpus 16 agcount 1 logblocks 3075
+sz 16M cpus 32 agcount 1 logblocks 3075
+sz 16M cpus 40 agcount 1 logblocks 3075
+sz 16M cpus 64 agcount 1 logblocks 3075
+sz 16M cpus 96 agcount 1 logblocks 3075
+sz 16M cpus 160 agcount 1 logblocks 3075
+sz 16M cpus 512 agcount 1 logblocks 3075
+-----------------
+sz 512M cpus 2 agcount 4 logblocks 16384
+sz 512M cpus 4 agcount 4 logblocks 16384
+sz 512M cpus 8 agcount 4 logblocks 16384
+sz 512M cpus 16 agcount 4 logblocks 16384
+sz 512M cpus 32 agcount 4 logblocks 16384
+sz 512M cpus 40 agcount 4 logblocks 16384
+sz 512M cpus 64 agcount 4 logblocks 16384
+sz 512M cpus 96 agcount 4 logblocks 16384
+sz 512M cpus 160 agcount 4 logblocks 16384
+sz 512M cpus 512 agcount 4 logblocks 16384
+-----------------
+sz 1G cpus 2 agcount 4 logblocks 16384
+sz 1G cpus 4 agcount 4 logblocks 16384
+sz 1G cpus 8 agcount 4 logblocks 16384
+sz 1G cpus 16 agcount 4 logblocks 22482
+sz 1G cpus 32 agcount 4 logblocks 44964
+sz 1G cpus 40 agcount 4 logblocks 56205
+sz 1G cpus 64 agcount 4 logblocks 65524
+sz 1G cpus 96 agcount 4 logblocks 65524
+sz 1G cpus 160 agcount 4 logblocks 65524
+sz 1G cpus 512 agcount 4 logblocks 65524
+-----------------
+sz 2G cpus 2 agcount 4 logblocks 16384
+sz 2G cpus 4 agcount 4 logblocks 16384
+sz 2G cpus 8 agcount 4 logblocks 16384
+sz 2G cpus 16 agcount 4 logblocks 25650
+sz 2G cpus 32 agcount 4 logblocks 51300
+sz 2G cpus 40 agcount 4 logblocks 64125
+sz 2G cpus 64 agcount 4 logblocks 102600
+sz 2G cpus 96 agcount 4 logblocks 131060
+sz 2G cpus 160 agcount 4 logblocks 131060
+sz 2G cpus 512 agcount 4 logblocks 131060
+-----------------
+sz 16G cpus 2 agcount 4 logblocks 16384
+sz 16G cpus 4 agcount 4 logblocks 16384
+sz 16G cpus 8 agcount 4 logblocks 16384
+sz 16G cpus 16 agcount 4 logblocks 25650
+sz 16G cpus 32 agcount 4 logblocks 51300
+sz 16G cpus 40 agcount 4 logblocks 64125
+sz 16G cpus 64 agcount 4 logblocks 102600
+sz 16G cpus 96 agcount 4 logblocks 153900
+sz 16G cpus 160 agcount 4 logblocks 256500
+sz 16G cpus 512 agcount 4 logblocks 521728
+-----------------
+sz 64G cpus 2 agcount 4 logblocks 16384
+sz 64G cpus 4 agcount 4 logblocks 16384
+sz 64G cpus 8 agcount 8 logblocks 16384
+sz 64G cpus 16 agcount 16 logblocks 25650
+sz 64G cpus 32 agcount 16 logblocks 51300
+sz 64G cpus 40 agcount 16 logblocks 64125
+sz 64G cpus 64 agcount 16 logblocks 102600
+sz 64G cpus 96 agcount 16 logblocks 153900
+sz 64G cpus 160 agcount 16 logblocks 256500
+sz 64G cpus 512 agcount 16 logblocks 521728
+-----------------
+sz 256G cpus 2 agcount 4 logblocks 32768
+sz 256G cpus 4 agcount 4 logblocks 32768
+sz 256G cpus 8 agcount 8 logblocks 32768
+sz 256G cpus 16 agcount 16 logblocks 32768
+sz 256G cpus 32 agcount 32 logblocks 51300
+sz 256G cpus 40 agcount 40 logblocks 64125
+sz 256G cpus 64 agcount 64 logblocks 102600
+sz 256G cpus 96 agcount 64 logblocks 153900
+sz 256G cpus 160 agcount 64 logblocks 256500
+sz 256G cpus 512 agcount 64 logblocks 521728
+-----------------
+sz 512G cpus 2 agcount 4 logblocks 65536
+sz 512G cpus 4 agcount 4 logblocks 65536
+sz 512G cpus 8 agcount 8 logblocks 65536
+sz 512G cpus 16 agcount 16 logblocks 65536
+sz 512G cpus 32 agcount 32 logblocks 65536
+sz 512G cpus 40 agcount 40 logblocks 65535
+sz 512G cpus 64 agcount 64 logblocks 102600
+sz 512G cpus 96 agcount 96 logblocks 153900
+sz 512G cpus 160 agcount 128 logblocks 256500
+sz 512G cpus 512 agcount 128 logblocks 521728
+-----------------
+sz 1T cpus 2 agcount 4 logblocks 131072
+sz 1T cpus 4 agcount 4 logblocks 131072
+sz 1T cpus 8 agcount 8 logblocks 131072
+sz 1T cpus 16 agcount 16 logblocks 131072
+sz 1T cpus 32 agcount 32 logblocks 131072
+sz 1T cpus 40 agcount 40 logblocks 131071
+sz 1T cpus 64 agcount 64 logblocks 131072
+sz 1T cpus 96 agcount 96 logblocks 153900
+sz 1T cpus 160 agcount 160 logblocks 256500
+sz 1T cpus 512 agcount 256 logblocks 521728
+-----------------
+sz 2T cpus 2 agcount 4 logblocks 262144
+sz 2T cpus 4 agcount 4 logblocks 262144
+sz 2T cpus 8 agcount 8 logblocks 262144
+sz 2T cpus 16 agcount 16 logblocks 262144
+sz 2T cpus 32 agcount 32 logblocks 262144
+sz 2T cpus 40 agcount 40 logblocks 262143
+sz 2T cpus 64 agcount 64 logblocks 262144
+sz 2T cpus 96 agcount 96 logblocks 262143
+sz 2T cpus 160 agcount 160 logblocks 262143
+sz 2T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 4T cpus 2 agcount 4 logblocks 521728
+sz 4T cpus 4 agcount 4 logblocks 521728
+sz 4T cpus 8 agcount 8 logblocks 521728
+sz 4T cpus 16 agcount 16 logblocks 521728
+sz 4T cpus 32 agcount 32 logblocks 521728
+sz 4T cpus 40 agcount 40 logblocks 521728
+sz 4T cpus 64 agcount 64 logblocks 521728
+sz 4T cpus 96 agcount 96 logblocks 521728
+sz 4T cpus 160 agcount 160 logblocks 521728
+sz 4T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 16T cpus 2 agcount 16 logblocks 521728
+sz 16T cpus 4 agcount 16 logblocks 521728
+sz 16T cpus 8 agcount 16 logblocks 521728
+sz 16T cpus 16 agcount 16 logblocks 521728
+sz 16T cpus 32 agcount 32 logblocks 521728
+sz 16T cpus 40 agcount 40 logblocks 521728
+sz 16T cpus 64 agcount 64 logblocks 521728
+sz 16T cpus 96 agcount 96 logblocks 521728
+sz 16T cpus 160 agcount 160 logblocks 521728
+sz 16T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 64T cpus 2 agcount 64 logblocks 521728
+sz 64T cpus 4 agcount 64 logblocks 521728
+sz 64T cpus 8 agcount 64 logblocks 521728
+sz 64T cpus 16 agcount 64 logblocks 521728
+sz 64T cpus 32 agcount 64 logblocks 521728
+sz 64T cpus 40 agcount 64 logblocks 521728
+sz 64T cpus 64 agcount 64 logblocks 521728
+sz 64T cpus 96 agcount 96 logblocks 521728
+sz 64T cpus 160 agcount 160 logblocks 521728
+sz 64T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 256T cpus 2 agcount 256 logblocks 521728
+sz 256T cpus 4 agcount 256 logblocks 521728
+sz 256T cpus 8 agcount 256 logblocks 521728
+sz 256T cpus 16 agcount 256 logblocks 521728
+sz 256T cpus 32 agcount 256 logblocks 521728
+sz 256T cpus 40 agcount 256 logblocks 521728
+sz 256T cpus 64 agcount 256 logblocks 521728
+sz 256T cpus 96 agcount 256 logblocks 521728
+sz 256T cpus 160 agcount 256 logblocks 521728
+sz 256T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 512T cpus 2 agcount 512 logblocks 521728
+sz 512T cpus 4 agcount 512 logblocks 521728
+sz 512T cpus 8 agcount 512 logblocks 521728
+sz 512T cpus 16 agcount 512 logblocks 521728
+sz 512T cpus 32 agcount 512 logblocks 521728
+sz 512T cpus 40 agcount 512 logblocks 521728
+sz 512T cpus 64 agcount 512 logblocks 521728
+sz 512T cpus 96 agcount 512 logblocks 521728
+sz 512T cpus 160 agcount 512 logblocks 521728
+sz 512T cpus 512 agcount 512 logblocks 521728
+-----------------
+sz 1P cpus 2 agcount 1024 logblocks 521728
+sz 1P cpus 4 agcount 1024 logblocks 521728
+sz 1P cpus 8 agcount 1024 logblocks 521728
+sz 1P cpus 16 agcount 1024 logblocks 521728
+sz 1P cpus 32 agcount 1024 logblocks 521728
+sz 1P cpus 40 agcount 1024 logblocks 521728
+sz 1P cpus 64 agcount 1024 logblocks 521728
+sz 1P cpus 96 agcount 1024 logblocks 521728
+sz 1P cpus 160 agcount 1024 logblocks 521728
+sz 1P cpus 512 agcount 1024 logblocks 521728
+-----------------
