On Sat, Sep 21, 2013 at 02:30:51PM +0200, Michael Olbrich wrote: > Hi, > > > > > > > An embedded system typically doesn't have an initrd. The kernel > > > boots directly into the rootfs on SD/eMMC. > > > > > > >>To my understanding, the UUID is different for each SD card/eMMC, correct? > > > > > > > >Yes by default. > > > > > > > >Although for an embedded product with a fixed eMMC, there's no reason > > > >you couldn't make every device have the same UUID for the fixed device. > > > > > > How do you make the eMMC on 1000 boards have the same UUID? > > > > The same way you ensure an identical partition table in these 1000 > > boards. The disk signature is just a four byte value at offset 440 in > > the MBR. Set this to your birthday or whatever on all boards, pass > > root=PARTUUID=<yourbirthday>-01 on all boards and you're done. > > Until someone inserts a SD-Card with the same disk signature... Indeed. That would be a nice way to boot your own rootfs on otherwise locked devices ;) Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
