Comment # 1 on bug 1043040 from zhen ren

The same issue also for lvcreate-usage.sh:

[ 0:18] lvcreate -L 8 -n $lv4 --readahead auto $vg
[ 0:18] #lvcreate-usage.sh:160+ lvcreate -L 8 -n LV4 --readahead auto
@PREFIX@vg
[ 0:18]   WARNING: This metadata update is NOT backed up.
[ 0:18]   @TESTDIR@/dev/mapper/@PREFIX@vg-LV4 not set up by udev: Falling back
to direct node creation.
[ 0:18]   The link @TESTDIR@/dev/@PREFIX@vg/LV4 should have been created by
udev but it was not found. Falling back to direct link creation.
[ 0:18]   Logical volume "LV4" created.
[ 0:18] check lv_field $vg/$lv4 lv_read_ahead "auto"
[ 0:18] #lvcreate-usage.sh:161+ check lv_field @PREFIX@vg/LV4 lv_read_ahead
auto
[ 0:18] check lv_field $vg/$lv4 lv_kernel_read_ahead "128.00k"
[ 0:18] #lvcreate-usage.sh:162+ check lv_field @PREFIX@vg/LV4
lv_kernel_read_ahead 128.00k
[ 0:18] lv_field: lv=@PREFIX@vg/LV4, field="lv_kernel_read_ahead",
actual="512.00k", expected="128.00k"
[ 0:18] set +vx; STACKTRACE; set -vx