Running 2.6.38 on my beagleboard, I can boot using nfs:- regulator_init_complete: VDVI: incomplete constraints, leaving on regulator_init_complete: VDAC: incomplete constraints, leaving on usb 1-2: new high speed USB device using ehci-omap and address 2 mmc0: host does not support reading read-only switch. assuming write-enable. mmc0: new high speed SDHC card at address 1234 usb 1-2: New USB device found, idVendor=0424, idProduct=9514 usb 1-2: New USB device strings: Mfr=0, Product=0, SerialNumber=0 mmcblk0: mmc0:1234 SA04G 3.67 GiB hub 1-2:1.0: USB hub found mmcblk0: p1 hub 1-2:1.0: 5 ports detected usb 1-2.1: new high speed USB device using ehci-omap and address 3 usb 1-2.1: New USB device found, idVendor=0424, idProduct=ec00 usb 1-2.1: New USB device strings: Mfr=0, Product=0, SerialNumber=0 smsc95xx v1.0.4 smsc95xx 1-2.1:1.0: usb0: register 'smsc95xx' at usb-ehci-omap.0-2.1, smsc95xx USB 2.0 Ethernet, 9e:79:dd:1e:2e:5c Sending DHCP requests . usb0: link up, 100Mbps, full-duplex, lpa 0x45E1 ., OK IP-Config: Got DHCP answer from 10.0.0.1, my address is 10.0.0.113 IP-Config: Complete: device=usb0, addr=10.0.0.113, mask=255.255.0.0, gw=10.0.0.1, host=10.0.0.113, domain=, nis-domain=(none), bootserver=10.0.0.1, rootserver=10.0.0.100, rootpath= VFS: Mounted root (nfs filesystem) on device 0:10. .... etc .... I have just tried out 2.6.39-rc1, and the usbnet is no longer detected:- regulator_init_complete: VDVI: incomplete constraints, leaving on regulator_init_complete: VDAC: incomplete constraints, leaving on mmc0: host does not support reading read-only switch. assuming write-enable. mmc0: new high speed SDHC card at address 1234 mmcblk0: mmc0:1234 SA04G 3.67 GiB mmcblk0: p1 VFS: Unable to mount root fs via NFS, trying floppy. VFS: Cannot open root device "nfs" or unknown-block(2,0) Please append a correct "root=" boot option; here are the available partitions: b300 3858432 mmcblk0 driver: mmcblk b301 72261 mmcblk0p1 00000000-0000-0000-0000-000000000mmcblk0p1 Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(2,0) I have tried a git bisect, but it seems to blame the wrong thing:- 087809fce28f50098d9c3ef1a6865c722f23afd2 is the first bad commit commit 087809fce28f50098d9c3ef1a6865c722f23afd2 Author: Jamie Iles Date: Fri Jan 21 14:11:52 2011 +0000 dmaengine/dw_dmac: don't scan descriptors if no xfers in progress Some hardware (picoChip picoXCell in particular) sometimes has the block transfer complete bit being set for a channel after the whole transfer has completed. If we don't have any transfers in the active list then don't bother to scan the descriptors. This often happens in normal operation and doesn't require the channel to be reset. v2: cleanup whitespace Signed-off-by: Jamie Iles Signed-off-by: Dan Williams :040000 040000 d0dac7f65b52fb1849f77056740d84d06530629f 211910a820dad07f0439410cc849c34909a62c2f M drivers I have attached my .config. Can anyone help ? Cheers Mark