I have build a ubuntu image & rootfs for OMP4, when it run on blaze, error occurs as below:

3.500366] regulator_init_complete: incomplete constraints, leaving VANA on
[ 3.508178] regulator_init_complete: incomplete constraints, leaving VUSIM on
[ 3.516082] regulator_init_complete: incomplete constraints, leaving VPP on
[ 3.527038] twl_rtc twl_rtc: setting system clock to 2000-01-01 00:10:30 UTC (946685430)
[ 3.535675] omap_vout omap_vout: 'lcd' Display already enabled
[ 3.541778] omap_vout omap_vout: 'lcd' Display already enabled
[ 3.547851] omap_vout omap_vout: 'lcd' Display already enabled
[ 3.554107] omap_vout omap_vout: : registered and initialized video device 0
[ 3.561584] omap_vout omap_vout: : registered and initialized video device 1
[ 3.569274] omap_wb: registered and initialized wb device 2 [v4l2]
[ 16.174285] Waiting 1sec before mounting root device...
[ 17.189575] EXT3-fs: barriers not enabled
[ 17.198059] kjournald starting. Commit interval 5 seconds
[ 17.216796] EXT3-fs (mmcblk1p2): using internal journal
[ 17.222259] EXT3-fs (mmcblk1p2): mounted filesystem with writeback data mode
[ 17.229644] VFS: Mounted root (ext3 filesystem) on device 179:10.
[ 17.244842] devtmpfs: mounted
[ 17.247955] Freeing init memory: 220K
* Asking all remaining processes to terminate... [ OK ]
* All processes ended within 1 seconds.... [ OK ]
* Deconfiguring network interfaces... [ OK ]
* Deactivating swap... [ OK ]
* Unmounting local filesystems... umount2: Device or resource busy
umount: none busy - remounted read-only
[ OK ]
* Will now halt
[ 20.781616] System halted.
[ 20.784454] System halted, OK to turn off power




Do you have any suggestions?