I'm trying to upgrade kernel from 4.14 to 4.18-rc3 (yes, I know 4.18 was released, but I am using a manufacturer-specific branch (linux-sunxi)). Get boot error (edited for brevity):

Gave up waiting for root device. ALERT!  /dev/mmcblk0p2 does not exist.
Dropping to a shell!

When I boot 4.14, /dev/mmcblk0p2 is mounted on /. It holds the fs. FWIW, mmcblk0p2 is not mentioned in /etc/fstab.

What can I try?

closed as too broad by Rui F Ribeiro, schily, slm Aug 13 '18 at 19:43

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  • is this on a Raspberry Pi, by chance? – Jeff Schaller Aug 13 '18 at 14:13
  • @JeffSchaller This is on FriendlyArm's Nanopi neo core 2 – user907323 Aug 13 '18 at 14:39
  • @GAD3R The contents of my /etc/fstab is: "/dev/mmcblk0p1 /boot vfat defaults 0 0". Are you suggesting adding a line for /dev/mmcblk0p2 ? – user907323 Aug 13 '18 at 14:41
  • 1
    @GAD3R I am using u-boot. /proc/cmdline contains root=/dev/mmcblk0p2 – user907323 Aug 13 '18 at 14:43