Hi I have made an bootable USB via dd command from hd.img image for a 386 architecture. The grub run, the kernel start to boot but when root file system has to be mount on root I see a kernel panic. I have put the right file system in the kernel (not module). The last part of console output is : sdb: sdb1 [ 3.016140] sd 33:0:0:0: [sdb] Attached SCSI removable disk [ 11.119960] VFS: Cannot open root device "sdb1" or unknown-block(8,17): error -2 [ 11.121978] Please append a correct "root=" boot option; here are the available partitions: [ 11.124194] 0800 524288 sda driver: sd [ 11.125492] 0810 3910180 sdb driver: sd [ 11.126782] 0811 298976 sdb1 00000000-0000-0000-0000-000000000000 [ 11.128686] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(8,17) [ 11.130895] Pid: 1, comm: swapper/0 Not tainted 3.5.7-Anto-Embedded #12 My impression is : kernel see the partition but can't read it. The other strange thing is UUID number 00000000-0000-0000-0000-000000000000 but if I mount the usb key in a linux machine the number is right and not 0 The kernel command line is : root=/dev/sdb1 console=ttyS1,115200 rootdelay=10 do you have same ideas regards, Antonio Righettini