boot serial output

[    0.029309] UDP-Lite hash table entries: 512 (order: 2, 16384 bytes)
[    0.029510] NET: Registered protocol family 1
[    0.029876] RPC: Registered named UNIX socket transport module.
[    0.029890] RPC: Registered udp transport module.
[    0.029895] RPC: Registered tcp transport module.
[    0.029901] RPC: Registered tcp NFSv4.1 backchannel transport module.
[    0.030696] futex hash table entries: 512 (order: 3, 32768 bytes)
[    0.031253] bounce pool size: 64 pages
[    0.039847] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 251)
[    0.039865] io scheduler noop registered
[    0.039871] io scheduler deadline registered
[    0.040066] io scheduler cfq registered (default)
[    0.042142] sun7i-a20-pinctrl 1c20800.pinctrl: initialized sunXi PIO driver
[    0.083858] Serial: 8250/16550 driver, 8 ports, IRQ sharing disabled
[    0.086355] console [ttyS0] disabled
[    0.106492] 1c28000.serial: ttyS0 at MMIO 0x1c28000 (irq = 33, base_baud = 1500000) is a U6_16550A
[    0.668228] console [ttyS0] enabled
[    0.673225] stmmaceth 1c50000.ethernet: no regulator found
[    0.678757] stmmaceth 1c50000.ethernet: no reset control found
[    0.684635]  Ring mode enabled
[    0.687687]  No HW DMA feature register supported
[    0.692223]  Normal descriptors
[    0.695544]  TX Checksum insertion supported
[    0.703514] libphy: stmmac: probed
[    0.706926] eth0: PHY ID 02430c54 at 1 IRQ 0 (stmmac-0:01) active
[    0.713417] mousedev: PS/2 mouse device common for all mice
[    0.719332] i2c /dev entries driver
[    0.723999] sunxi-wdt 1c20c90.watchdog: Watchdog enabled (timeout=16 sec, nowayout=0)
[    0.732797] sunxi-mmc 1c0f000.mmc: Got CD GPIO #225.
[    0.771363] sunxi-mmc 1c0f000.mmc: base:0xf00b6000 irq:64
[    0.778100] TCP: cubic registered
[    0.781451] NET: Registered protocol family 17
[    0.785978] Registering SWP/SWPB emulation handler
[    0.791197] vcc3v0: disabling
[    0.794702] ahci-5v: 5000 mV
[    0.797922] usb1-vbus: 5000 mV
[    0.801270] usb2-vbus: 5000 mV
[    0.805173] Waiting for root device /dev/mmcblk0p2...
[    0.808136] mmc0: host does not support reading read-only switch. assuming write-enable.
[    0.810431] mmc0: new high speed SDHC card at address 0001
[    0.810797] mmcblk0: mmc0:0001 00000 29.8 GiB
[    0.829180]  mmcblk0: p1 p2 p3
[    0.931442] List of all partitions:
[    0.934942] b300        31259136 mmcblk0  driver: mmcblk
[    0.940262]   b301           16384 mmcblk0p1 000b2bf1-01
[    0.945610]   b302         2124800 mmcblk0p2 000b2bf1-02
[    0.950926]   b303         1106944 mmcblk0p3 000b2bf1-03
[    0.956252] No filesystem could mount root, tried:
[    0.961137] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(179,2)
[    0.969566] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 3.15.0-81004-ga076583 #1
[    0.976810] [<c0013e44>] (unwind_backtrace) from [<c00112a4>] (show_stack+0x10/0x14)
[    0.984555] [<c00112a4>] (show_stack) from [<c02a7c6c>] (dump_stack+0x88/0x98)
[    0.991774] [<c02a7c6c>] (dump_stack) from [<c02a76e4>] (panic+0xa0/0x1f8)
[    0.998650] [<c02a76e4>] (panic) from [<c03a2024>] (mount_block_root+0x21c/0x230)
[    1.006130] [<c03a2024>] (mount_block_root) from [<c03a2140>] (mount_root+0x108/0x110)
[    1.014041] [<c03a2140>] (mount_root) from [<c03a2294>] (prepare_namespace+0x14c/0x190)
[    1.022039] [<c03a2294>] (prepare_namespace) from [<c03a1c64>] (kernel_init_freeable+0x1c8/0x1d8)
[    1.030904] [<c03a1c64>] (kernel_init_freeable) from [<c02a6acc>] (kernel_init+0xc/0xe8)
[    1.038987] [<c02a6acc>] (kernel_init) from [<c000e3b8>] (ret_from_fork+0x14/0x3c)
[    1.046549] CPU0: stopping
[    1.049258] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.15.0-81004-ga076583 #1
[    1.056479] [<c0013e44>] (unwind_backtrace) from [<c00112a4>] (show_stack+0x10/0x14)
[    1.064217] [<c00112a4>] (show_stack) from [<c02a7c6c>] (dump_stack+0x88/0x98)
[    1.071433] [<c02a7c6c>] (dump_stack) from [<c0013190>] (handle_IPI+0x150/0x16c)
[    1.078823] [<c0013190>] (handle_IPI) from [<c0008574>] (gic_handle_irq+0x58/0x5c)
[    1.086387] [<c0008574>] (gic_handle_irq) from [<c0011dc0>] (__irq_svc+0x40/0x50)
[    1.093857] Exception stack(0xc03cff68 to 0xc03cffb0)
[    1.098905] ff60:                   eefe55c0 00000000 00000aa6 00000000 c03ce038 c03d6418
[    1.107073] ff80: c03d6468 c02ad8c4 c03f7917 c03f7917 c03ce000 00000000 00000000 c03cffb0
[    1.115239] ffa0: c000eef8 c000eefc 60000113 ffffffff
[    1.120290] [<c0011dc0>] (__irq_svc) from [<c000eefc>] (arch_cpu_idle+0x2c/0x30)
[    1.127681] [<c000eefc>] (arch_cpu_idle) from [<c004f558>] (cpu_startup_entry+0x100/0x14c)
[    1.135940] [<c004f558>] (cpu_startup_entry) from [<c03a1a90>] (start_kernel+0x2d4/0x2e0)
[    1.144110] [<c03a1a90>] (start_kernel) from [<40008074>] (0x40008074)
[    1.150633] Rebooting in 10 seconds..