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+There is a problem with udev: when a volume is created, there is a delay
+before corresponding /dev/ubiX_Y device node is created by udev, so some
+tests fail because of this. The symptom is error messages like
+"cannot open /dev/ubi0_0".
+
+One possible solution of this problem is to pre-create UBI device and volume
+nodes. There is even a script which may be used for this in ubi-utils/scripts/.
+But this is not enough because udev will still remove and re-create the nodes
+and tests will still fail. So you need to stop removing device nodes using
+the following udev rule:
+
+ KERNEL=="ubi*_*", ACTION=="remove", OPTIONS+="ignore_device"
+
+In our Ubuntu distribution we put that to new file:
+/etc/udev/rules.d/50-local.rules
+
+Another possibility is to call udevsettle utility in libubi after the volume
+has been created See src/libubi.c - the call is compiled in only if
+UDEV_SETTLE_HACK is defined. This is anyway an ugly hack, but works, although
+makes the tests slower. Suggestions are welcome.
+
+So, if you have udevsettel unility in your system, you do not have to do
+anyting, and the tests should work, because we compile libubi with
+UDEV_SETTLE_HACK. Otherwise, you should remove -D UDEV_SETTLE_HACK
+from the makefile and pre-create UBI device nodes.