Subject: RPI 4b PXE boot - /dev/nfs: Can't open blockdev

From: Pietro Sammarco <[email-masked]>
Date: Sun, 7 Nov 2021 12:05:07 +0000

Hello folks,

I installed AlpineLinux persistent install on mmc on my RPI 4b, rsynced 
it into the NAS and I am now trying to PXE boot it.The kernel boots 
fine, however mounting root fails with the following error: "/dev/nfs: 
Can't open blockdev".

*PXE general setup*

172.12.1.1 is the TFTP server which serves the kernel + bootfiles, and 
the boot folder is in /var/tftpboot/node0.
172.12.1.57 is the NAS which serves the rootfs. NFSv3 is being used and 
the rootfs is in /zfs/netboot/node0.

admin@cockbox ~ $ cat /etc/exports  |grep -v '#'
/zfs/netboot/node0 *(rw,sync,no_subtree_check,no_root_squash)
admin@cockbox ~ $ showmount -e
Export list for cockbox:
/zfs/netboot/node0 *
admin@cockbox ~ $ showmount -e 172.12.1.1
Export list for 172.12.1.1:
/var/tftpboot/node0 *
/var/tftpboot/kube4 *
admin@cockbox ~ $
<<<

*RPI setup*

pi@raspberrypi:~ $ rpi-eeprom-config
[all]
BOOT_UART=1
BOOT_ORDER=0x21
DHCP_TIMEOUT=45000
DHCP_REQ_TIMEOUT=4000
TFTP_FILE_TIMEOUT=30000
TFTP_PREFIX=1
TFTP_PREFIX_STR=node0/
WAKE_ON_GPIO=1
POWER_OFF_ON_HALT=0
pi@raspberrypi:~ $

vswitch0:~$ cat /var/tftpboot/node0/cmdline.txt
console=serial0,115200 console=tty1 root=/dev/nfs 
nfsroot=172.12.1.57:/zfs/netboot/node0,vers=3,proto=tcp rw ip=dhcp 
rootwait cgroup_memory=1 cgroup_enable=memory
vswitch0:~$ cat /var/tftpboot/node0/usercfg.txt
enable_uart=1
dtparam=uart0=on
uart_2ndstage=1
disable_splash=1
dtoverlay=disable-bt
boot_delay=0
initial_turbo=1
gpu_mem=32
vswitch0:~$
<<<

*Boot logs*

RPi: BOOTLOADER release VERSION:39e76747 DATE: Sep 27 2021 TIME: 
14:30:29 BOOTMODE: 0x00000006 part: 0 BUILD_TIMESTAMP=1632749428 
0xca63daf5 0x00d03114 0x00052348
PM_RSTS: 0x00001000
part 00000000 reset_info 00000000
uSD voltage 3.3V
Initialising SDRAM 'Micron' 32Gb x2 total-size: 64 Gbit 3200

XHCI-STOP
xHC ver: 256 HCS: 05000420 fc000031 00e70004 HCC: 002841eb
USBSTS 11
xHC ver: 256 HCS: 05000420 fc000031 00e70004 HCC: 002841eb
xHC ports 5 slots 32 intrs 4
Boot mode: SD (01) order 2
SD HOST: 250000000 CTL0: 0x00000000 BUS: 100000 Hz actual: 100000 HZ 
div: 2500 (1250) status: 0x1fff0000 delay: 1080
SD HOST: 250000000 CTL0: 0x00000f00 BUS: 100000 Hz actual: 100000 HZ 
div: 2500 (1250) status: 0x1fff0000 delay: 1080
EMMC
SD retry 1 oc 0
SD HOST: 250000000 CTL0: 0x00000000 BUS: 100000 Hz actual: 100000 HZ 
div: 2500 (1250) status: 0x1fff0000 delay: 1080
SD retry 2 oc 0
SD HOST: 250000000 CTL0: 0x00000000 BUS: 100000 Hz actual: 100000 HZ 
div: 2500 (1250) status: 0x1fff0000 delay: 1080
SDV1
SD retry 3 oc 0
SD HOST: 250000000 CTL0: 0x00000000 BUS: 100000 Hz actual: 100000 HZ 
div: 2500 (1250) status: 0x1fff0000 delay: 1080
SD CMD: 0x371a0010 (55) 0x0 0x1fff0001
Failed to open device: 'sdcard' (cmd 371a0010 status 1fff0001)
Retry SD 1
SD HOST: 250000000 CTL0: 0x00000000 BUS: 100000 Hz actual: 100000 HZ 
div: 2500 (1250) status: 0x1fff0000 delay: 1080
SD HOST: 250000000 CTL0: 0x00000f00 BUS: 100000 Hz actual: 100000 HZ 
div: 2500 (1250) status: 0x1fff0000 delay: 1080
EMMC
SD retry 1 oc 0
SD HOST: 250000000 CTL0: 0x00000000 BUS: 100000 Hz actual: 100000 HZ 
div: 2500 (1250) status: 0x1fff0000 delay: 1080
SD retry 2 oc 0
SD HOST: 250000000 CTL0: 0x00000000 BUS: 100000 Hz actual: 100000 HZ 
div: 2500 (1250) status: 0x1fff0000 delay: 1080
SDV1
SD retry 3 oc 0
SD HOST: 250000000 CTL0: 0x00000000 BUS: 100000 Hz actual: 100000 HZ 
div: 2500 (1250) status: 0x1fff0000 delay: 1080
SD CMD: 0x371a0010 (55) 0x0 0x1fff0001
Failed to open device: 'sdcard' (cmd 371a0010 status 1fff0001)
Boot mode: NETWORK (02) order 0
GENET: RESET_PHY
NET_BOOT: dc:a6:32:d6:35:2e wait for link TFTP: 0.0.0.0
LINK STATUS: speed: 1000 full duplex
Link ready
GENET START: 64 16 32
GENET: UMAC_START 0xdca632d6 0x352e0000
RX: 0 IP: 0 IPV4: 0 MAC: 0 UDP: 0 UDP RECV: 0 IP_CSUM_ERR: 0 UDP_CSUM_ERR: 0
DHCP src: fe:ad:82:55:02:0e 172.12.1.1
YI_ADDR 172.12.1.71
OPTIONS:-
     op: 53 len:   1 DHCP recv OFFER (2) expect OFFER
     op: 54 len:   4 172.12.1.1
     op: 51 len:   4
     op:  1 len:   4 255.255.255.0
     op:  3 len:   4 172.12.1.1
     op: 66 len:  10 172.12.1.1[66]: 172.12.1.1

DHCP src: fe:ad:82:55:02:0e 172.12.1.1
YI_ADDR 172.12.1.71
OPTIONS:-
     op: 53 len:   1 DHCP recv ACK (5) expect ACK
     op: 54 len:   4 172.12.1.1
     op: 51 len:   4
     op:  1 len:   4 255.255.255.0
     op:  3 len:   4 172.12.1.1
     op:  6 len:   8
     op: 12 len:   5
     op: 66 len:  10 172.12.1.1[66]: 172.12.1.1

     op: 15 len:  14
NET 172.12.1.71 255.255.255.0 gw 0.0.0.0 tftp 172.12.1.1
ARP 172.12.1.1 fe:ad:82:55:02:0e
NET 172.12.1.71 255.255.255.0 gw 0.0.0.0 tftp 172.12.1.1
RX: 3 IP: 0 IPV4: 2 MAC: 2 UDP: 2 UDP RECV: 2 IP_CSUM_ERR: 0 UDP_CSUM_ERR: 0
TFTP_GET: fe:ad:82:55:02:0e 172.12.1.1 node0/start4.elf

RX: 3 IP: 0 IPV4: 2 MAC: 2 UDP: 2 UDP RECV: 2 IP_CSUM_ERR: 0 UDP_CSUM_ERR: 0
RX: 4 IP: 0 IPV4: 3 MAC: 3 UDP: 3 UDP RECV: 3 IP_CSUM_ERR: 0 UDP_CSUM_ERR: 0
TFTP_GET: fe:ad:82:55:02:0e 172.12.1.1 node0/config.txt

RX: 4 IP: 0 IPV4: 3 MAC: 3 UDP: 3 UDP RECV: 3 IP_CSUM_ERR: 0 UDP_CSUM_ERR: 0
TFTP: complete 408
RX: 6 IP: 0 IPV4: 5 MAC: 5 UDP: 5 UDP RECV: 5 IP_CSUM_ERR: 0 UDP_CSUM_ERR: 0
Read node0/config.txt bytes      408 hnd 0x00000000
TFTP_GET: fe:ad:82:55:02:0e 172.12.1.1 node0/pieeprom.sig

RX: 6 IP: 0 IPV4: 5 MAC: 5 UDP: 5 UDP RECV: 5 IP_CSUM_ERR: 0 UDP_CSUM_ERR: 0
TFTP 1: File not found
RX: 7 IP: 0 IPV4: 6 MAC: 6 UDP: 6 UDP RECV: 6 IP_CSUM_ERR: 0 UDP_CSUM_ERR: 0
Read node0/pieeprom.upd failed
TFTP_GET: fe:ad:82:55:02:0e 172.12.1.1 node0/recover4.elf

RX: 7 IP: 0 IPV4: 6 MAC: 6 UDP: 6 UDP RECV: 6 IP_CSUM_ERR: 0 UDP_CSUM_ERR: 0
TFTP 1: File not found
RX: 8 IP: 0 IPV4: 7 MAC: 7 UDP: 7 UDP RECV: 7 IP_CSUM_ERR: 0 UDP_CSUM_ERR: 0
Read node0/recover4.elf failed
TFTP_GET: fe:ad:82:55:02:0e 172.12.1.1 node0/recovery.elf

RX: 8 IP: 0 IPV4: 7 MAC: 7 UDP: 7 UDP RECV: 7 IP_CSUM_ERR: 0 UDP_CSUM_ERR: 0
TFTP 1: File not found
RX: 9 IP: 0 IPV4: 8 MAC: 8 UDP: 8 UDP RECV: 8 IP_CSUM_ERR: 0 UDP_CSUM_ERR: 0
Read node0/recovery.elf failed
TFTP_GET: fe:ad:82:55:02:0e 172.12.1.1 node0/start4.elf

RX: 9 IP: 0 IPV4: 8 MAC: 8 UDP: 8 UDP RECV: 8 IP_CSUM_ERR: 0 UDP_CSUM_ERR: 0
TFTP: complete 2235712
RX: 146 IP: 0 IPV4: 145 MAC: 145 UDP: 145 UDP RECV: 145 IP_CSUM_ERR: 0 
UDP_CSUM_ERR: 0
Read node0/start4.elf bytes  2235712 hnd 0x00000000
TFTP_GET: fe:ad:82:55:02:0e 172.12.1.1 node0/fixup4.dat

RX: 146 IP: 0 IPV4: 145 MAC: 145 UDP: 145 UDP RECV: 145 IP_CSUM_ERR: 0 
UDP_CSUM_ERR: 0
TFTP: complete 5407
RX: 153 IP: 0 IPV4: 152 MAC: 152 UDP: 152 UDP RECV: 152 IP_CSUM_ERR: 0 
UDP_CSUM_ERR: 0
Read node0/fixup4.dat bytes     5407 hnd 0x00000000
Firmware: 40787ee5905644f639a2a0f6e00ae12e517a2211 Aug  3 2021 18:14:56
0x00d03114 0x00000000 0x00000fff
MEM GPU: 76 ARM: 948 TOTAL: 1024
Starting start4.elf @ 0xfec00200 partition -1
Stopping network
RX: 153 IP: 0 IPV4: 152 MAC: 152 UDP: 152 UDP RECV: 152 IP_CSUM_ERR: 0 
UDP_CSUM_ERR: 0
RX: 153 IP: 0 IPV4: 152 MAC: 152 UDP: 152 UDP RECV: 152 IP_CSUM_ERR: 0 
UDP_CSUM_ERR: 0
GENET STOP: 0
+
[    0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd083]
[    0.000000] Linux version 5.10.61-0-rpi4 
(buildozer@build-3-14-aarch64) (gcc (Alpine 10.3.1_git20210424) 10.3.1 
20210424, GNU ld (GNU Binutils) 2.35.2) #1-Alpine SMP PREEMPT Thu Aug 26 
22:38:20 UTC 2021
[    0.000000] random: fast init done
[    0.000000] Machine model: Raspberry Pi 4 Model B Rev 1.4
[    0.000000] efi: UEFI not found.
[    0.000000] Reserved memory: created CMA memory pool at 
0x000000002a800000, size 64 MiB
[    0.000000] OF: reserved mem: initialized node linux,cma, compatible 
id shared-dma-pool
[    0.000000] Zone ranges:
[    0.000000]   DMA      [mem 0x0000000000000000-0x000000003fffffff]
[    0.000000]   DMA32    [mem 0x0000000040000000-0x00000000ffffffff]
[    0.000000]   Normal   [mem 0x0000000100000000-0x00000001ffffffff]
[    0.000000] Movable zone start for each node
[    0.000000] Early memory node ranges
[    0.000000]   node   0: [mem 0x0000000000000000-0x000000003b3fffff]
[    0.000000]   node   0: [mem 0x0000000040000000-0x00000000fbffffff]
[    0.000000]   node   0: [mem 0x0000000100000000-0x00000001ffffffff]
[    0.000000] Initmem setup node 0 [mem 
0x0000000000000000-0x00000001ffffffff]
[    0.000000] percpu: Embedded 32 pages/cpu s91096 r8192 d31784 u131072
[    0.000000] Detected PIPT I-cache on CPU0
[    0.000000] CPU features: detected: Spectre-v2
[    0.000000] CPU features: detected: Spectre-v4
[    0.000000] CPU features: detected: ARM errata 1165522, 1319367, or 
1530923
[    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 
2028848
[    0.000000] Kernel command line: coherent_pool=1M 8250.nr_uarts=1 
snd_bcm2835.enable_compat_alsa=0 snd_bcm2835.enable_hdmi=1 
bcm2708_fb.fbwidth=0 bcm2708_fb.fbheight=0 bcm2708_fb.fbswap=1 
smsc95xx.macaddr=DC:A6:32:D6:35:2E vc_mem.mem_base=0x3ec00000 
vc_mem.mem_size=0x40000000  console=ttyAMA0,115200 console=tty1 
root=/dev/nfs nfsroot=172.12.1.57:/zfs/netboot/node0,vers=3,proto=tcp rw 
ip=dhcp rootwait cgroup_memory=1 cgroup_enable=memory
[    0.000000] cgroup: Enabling memory control group subsystem
[    0.000000] Dentry cache hash table entries: 1048576 (order: 11, 
8388608 bytes, linear)
[    0.000000] Inode-cache hash table entries: 524288 (order: 10, 
4194304 bytes, linear)
[    0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
[    0.000000] software IO TLB: mapped [mem 
0x0000000037400000-0x000000003b400000] (64MB)
[    0.000000] Memory: 7927868K/8245248K available (10944K kernel code, 
1944K rwdata, 3944K rodata, 2560K init, 1251K bss, 251844K reserved, 
65536K cma-reserved)
[    0.000000] random: get_random_u64 called from 
__kmem_cache_create+0x28/0x4c0 with crng_init=1
[    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=4, Nodes=1
[    0.000000] rcu: Preemptible hierarchical RCU implementation.
[    0.000000] rcu:     RCU event tracing is enabled.
[    0.000000] rcu:     RCU restricting CPUs from NR_CPUS=256 to 
nr_cpu_ids=4.
[    0.000000]     Trampoline variant of Tasks RCU enabled.
[    0.000000]     Tracing variant of Tasks RCU enabled.
[    0.000000] rcu: RCU calculated value of scheduler-enlistment delay 
is 25 jiffies.
[    0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=4
[    0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
[    0.000000] GIC: Using split EOI/Deactivate mode
[    0.000000] arch_timer: cp15 timer(s) running at 54.00MHz (phys).
[    0.000000] clocksource: arch_sys_counter: mask: 0xffffffffffffff 
max_cycles: 0xc743ce346, max_idle_ns: 440795203123 ns
[    0.000003] sched_clock: 56 bits at 54MHz, resolution 18ns, wraps 
every 4398046511102ns
[    0.000114] Console: colour dummy device 80x25
[    0.000311] printk: console [tty1] enabled
[    0.000343] Calibrating delay loop (skipped), value calculated using 
timer frequency.. 108.00 BogoMIPS (lpj=216000)
[    0.000360] pid_max: default: 32768 minimum: 301
[    0.000455] LSM: Security Framework initializing
[    0.000604] Mount-cache hash table entries: 16384 (order: 5, 131072 
bytes, linear)
[    0.000669] Mountpoint-cache hash table entries: 16384 (order: 5, 
131072 bytes, linear)
[    0.002015] rcu: Hierarchical SRCU implementation.
[    0.002524] EFI services will not be available.
[    0.002757] smp: Bringing up secondary CPUs ...
[    0.003175] Detected PIPT I-cache on CPU1
[    0.003215] CPU1: Booted secondary processor 0x0000000001 [0x410fd083]
[    0.003682] Detected PIPT I-cache on CPU2
[    0.003702] CPU2: Booted secondary processor 0x0000000002 [0x410fd083]
[    0.004195] Detected PIPT I-cache on CPU3
[    0.004214] CPU3: Booted secondary processor 0x0000000003 [0x410fd083]
[    0.004273] smp: Brought up 1 node, 4 CPUs
[    0.004290] SMP: Total of 4 processors activated.
[    0.004299] CPU features: detected: 32-bit EL0 Support
[    0.004308] CPU features: detected: CRC32 instructions
[    0.004316] CPU features: detected: 32-bit EL1 Support
[    0.017731] CPU: All CPU(s) started at EL2
[    0.017769] alternatives: patching kernel code
[    0.018792] devtmpfs: initialized
[    0.023293] Enabled cp15_barrier support
[    0.023328] Enabled setend support
[    0.023612] clocksource: jiffies: mask: 0xffffffff max_cycles: 
0xffffffff, max_idle_ns: 7645041785100000 ns
[    0.023637] futex hash table entries: 1024 (order: 4, 65536 bytes, 
linear)
[    0.024976] pinctrl core: initialized pinctrl subsystem
[    0.026297] DMI not present or invalid.
[    0.026518] NET: Registered protocol family 16
[    0.027707] DMA: preallocated 1024 KiB GFP_KERNEL pool for atomic 
allocations
[    0.027819] DMA: preallocated 1024 KiB GFP_KERNEL|GFP_DMA pool for 
atomic allocations
[    0.028190] DMA: preallocated 1024 KiB GFP_KERNEL|GFP_DMA32 pool for 
atomic allocations
[    0.028252] audit: initializing netlink subsys (disabled)
[    0.028394] audit: type=2000 audit(0.028:1): state=initialized 
audit_enabled=0 res=1
[    0.029752] thermal_sys: Registered thermal governor 'step_wise'
[    0.030087] cpuidle: using governor menu
[    0.030206] hw-breakpoint: found 6 breakpoint and 4 watchpoint registers.
[    0.030285] ASID allocator initialised with 65536 entries
[    0.030417] Serial: AMBA PL011 UART driver
[    0.044885] bcm2835-mbox fe00b880.mailbox: mailbox enabled
[    0.052106] raspberrypi-firmware soc:firmware: Attached to firmware 
from 2021-08-03T18:14:56, variant start
[    0.056106] raspberrypi-firmware soc:firmware: Firmware hash is 
40787ee5905644f639a2a0f6e00ae12e517a2211
[    0.088416] bcm2835-dma fe007000.dma: DMA legacy API manager, 
dmachans=0x1
[    0.090312] vgaarb: loaded
[    0.090590] SCSI subsystem initialized
[    0.090732] usbcore: registered new interface driver usbfs
[    0.090766] usbcore: registered new interface driver hub
[    0.090815] usbcore: registered new device driver usb
[    0.090982] usb_phy_generic phy: supply vcc not found, using dummy 
regulator
[    0.092191] clocksource: Switched to clocksource arch_sys_counter
[    0.501830] VFS: Disk quotas dquot_6.6.0
[    0.501888] VFS: Dquot-cache hash table entries: 512 (order 0, 4096 
bytes)
[    0.501963] FS-Cache: Loaded
[    0.502098] CacheFiles: Loaded
[    0.509226] NET: Registered protocol family 2
[    0.509827] IP idents hash table entries: 131072 (order: 8, 1048576 
bytes, linear)
[    0.512315] tcp_listen_portaddr_hash hash table entries: 4096 (order: 
4, 65536 bytes, linear)
[    0.512368] TCP established hash table entries: 65536 (order: 7, 
524288 bytes, linear)
[    0.512557] TCP bind hash table entries: 65536 (order: 8, 1048576 
bytes, linear)
[    0.513450] TCP: Hash tables configured (established 65536 bind 65536)
[    0.513659] UDP hash table entries: 4096 (order: 5, 131072 bytes, linear)
[    0.513728] UDP-Lite hash table entries: 4096 (order: 5, 131072 
bytes, linear)
[    0.513971] NET: Registered protocol family 1
[    0.514478] RPC: Registered named UNIX socket transport module.
[    0.514491] RPC: Registered udp transport module.
[    0.514498] RPC: Registered tcp transport module.
[    0.514506] RPC: Registered tcp NFSv4.1 backchannel transport module.
[    0.514519] PCI: CLS 0 bytes, default 64
[    0.514668] Trying to unpack rootfs image as initramfs...
[    0.650644] Freeing initrd memory: 4808K
[    0.651520] hw perfevents: enabled with armv8_cortex_a72 PMU driver, 
7 counters available
[    0.651674] kvm [1]: IPA Size Limit: 44 bits
[    0.652165] kvm [1]: vgic interrupt IRQ9
[    0.652358] kvm [1]: Hyp mode initialized successfully
[    0.653462] Initialise system trusted keyrings
[    0.653618] workingset: timestamp_bits=46 max_order=21 bucket_order=0
[    0.656282] zbud: loaded
[    0.657103] FS-Cache: Netfs 'nfs' registered for caching
[    0.657399] NFS: Registering the id_resolver key type
[    0.657426] Key type id_resolver registered
[    0.657434] Key type id_legacy registered
[    0.657498] nfs4filelayout_init: NFSv4 File Layout Driver Registering...
[    0.657509] nfs4flexfilelayout_init: NFSv4 Flexfile Layout Driver 
Registering...
[    0.658034] Key type asymmetric registered
[    0.658045] Asymmetric key parser 'x509' registered
[    0.658082] Block layer SCSI generic (bsg) driver version 0.4 loaded 
(major 249)
[    0.658192] io scheduler mq-deadline registered
[    0.658202] io scheduler kyber registered
[    0.659972] brcm-pcie fd500000.pcie: host bridge /scb/pcie@7d500000 
ranges:
[    0.659999] brcm-pcie fd500000.pcie:   No bus range found for 
/scb/pcie@7d500000, using [bus 00-ff]
[    0.660030] brcm-pcie fd500000.pcie:      MEM 
0x0600000000..0x063fffffff -> 0x00c0000000
[    0.660064] brcm-pcie fd500000.pcie:   IB MEM 
0x0000000000..0x00bfffffff -> 0x0400000000
[    0.726249] brcm-pcie fd500000.pcie: link up, 5.0 GT/s PCIe x1 (SSC)
[    0.726432] brcm-pcie fd500000.pcie: PCI host bridge to bus 0000:00
[    0.726445] pci_bus 0000:00: root bus resource [bus 00-ff]
[    0.726456] pci_bus 0000:00: root bus resource [mem 
0x600000000-0x63fffffff] (bus address [0xc0000000-0xffffffff])
[    0.726499] pci 0000:00:00.0: [14e4:2711] type 01 class 0x060400
[    0.726601] pci 0000:00:00.0: PME# supported from D0 D3hot
[    0.728065] pci 0000:00:00.0: bridge configuration invalid ([bus 
00-00]), reconfiguring
[    0.728279] pci 0000:01:00.0: [1106:3483] type 00 class 0x0c0330
[    0.728369] pci 0000:01:00.0: reg 0x10: [mem 0x00000000-0x00000fff 64bit]
[    0.728640] pci 0000:01:00.0: PME# supported from D0 D3hot
[    0.745454] pci_bus 0000:01: busn_res: [bus 01-ff] end is updated to 01
[    0.745481] pci 0000:00:00.0: BAR 8: assigned [mem 
0x600000000-0x6000fffff]
[    0.745494] pci 0000:01:00.0: BAR 0: assigned [mem 
0x600000000-0x600000fff 64bit]
[    0.745516] pci 0000:00:00.0: PCI bridge to [bus 01]
[    0.745529] pci 0000:00:00.0:   bridge window [mem 
0x600000000-0x6000fffff]
[    0.745833] bcm2708_fb soc:fb: Unable to determine number of FBs. 
Disabling driver.
[    0.745853] bcm2708_fb: probe of soc:fb failed with error -2
[    0.747914] Serial: 8250/16550 driver, 1 ports, IRQ sharing enabled
[    0.749367] iproc-rng200 fe104000.rng: hwrng registered
[    0.749563] vc-mem: phys_addr:0x00000000 mem_base=0x3ec00000 
mem_size:0x40000000(1024 MiB)
[    0.750131] gpiomem-bcm2835 fe200000.gpiomem: Initialised: Registers 
at 0xfe200000
[    0.750363] cacheinfo: Unable to detect cache hierarchy for CPU 0
[    0.755745] brd: module loaded
[    0.761988] loop: module loaded
[    0.762874] Loading iSCSI transport class v2.0-870.
[    0.764790] libphy: Fixed MDIO Bus: probed
[    0.765706] bcmgenet fd580000.ethernet: GENET 5.0 EPHY: 0x0000
[    0.776205] libphy: bcmgenet MII bus: probed
[    0.828349] unimac-mdio unimac-mdio.-19: Broadcom UniMAC MDIO bus
[    0.829636] usbcore: registered new interface driver r8152
[    0.829745] usbcore: registered new interface driver lan78xx
[    0.829825] usbcore: registered new interface driver smsc95xx
[    0.877558] pci 0000:00:00.0: enabling device (0000 -> 0002)
[    0.877753] xhci_hcd 0000:01:00.0: xHCI Host Controller
[    0.877811] xhci_hcd 0000:01:00.0: new USB bus registered, assigned 
bus number 1
[    0.878531] xhci_hcd 0000:01:00.0: hcc params 0x002841eb hci version 
0x100 quirks 0x0000060000000890
[    0.879799] usb usb1: New USB device found, idVendor=1d6b, 
idProduct=0002, bcdDevice= 5.10
[    0.879830] usb usb1: New USB device strings: Mfr=3, Product=2, 
SerialNumber=1
[    0.879854] usb usb1: Product: xHCI Host Controller
[    0.879874] usb usb1: Manufacturer: Linux 5.10.61-0-rpi4 xhci-hcd
[    0.879895] usb usb1: SerialNumber: 0000:01:00.0
[    0.880706] hub 1-0:1.0: USB hub found
[    0.880827] hub 1-0:1.0: 1 port detected
[    0.881461] xhci_hcd 0000:01:00.0: xHCI Host Controller
[    0.881499] xhci_hcd 0000:01:00.0: new USB bus registered, assigned 
bus number 2
[    0.881533] xhci_hcd 0000:01:00.0: Host supports USB 3.0 SuperSpeed
[    0.881918] usb usb2: New USB device found, idVendor=1d6b, 
idProduct=0003, bcdDevice= 5.10
[    0.881947] usb usb2: New USB device strings: Mfr=3, Product=2, 
SerialNumber=1
[    0.881970] usb usb2: Product: xHCI Host Controller
[    0.881990] usb usb2: Manufacturer: Linux 5.10.61-0-rpi4 xhci-hcd
[    0.882011] usb usb2: SerialNumber: 0000:01:00.0
[    0.882701] hub 2-0:1.0: USB hub found
[    0.882775] hub 2-0:1.0: 4 ports detected
[    0.884270] dwc_otg: version 3.00a 10-AUG-2012 (platform bus)
[    0.885072] usbcore: registered new interface driver uas
[    0.885189] usbcore: registered new interface driver usb-storage
[    0.885446] mousedev: PS/2 mouse device common for all mice
[    0.887637] bcm2835-wdt bcm2835-wdt: Broadcom BCM2835 watchdog timer
[    0.890823] sdhci: Secure Digital Host Controller Interface driver
[    0.890862] sdhci: Copyright(c) Pierre Ossman
[    0.891494] mmc-bcm2835 fe300000.mmcnr: could not get clk, deferring 
probe
[    0.891996] sdhci-pltfm: SDHCI platform and OF driver helper
[    0.894815] ledtrig-cpu: registered to indicate activity on CPUs
[    0.895280] hid: raw HID events driver (C) Jiri Kosina
[    0.895498] usbcore: registered new interface driver usbhid
[    0.895520] usbhid: USB HID core driver
[    0.895872] ashmem: initialized
[    0.903676] Initializing XFRM netlink socket
[    0.903847] Key type dns_resolver registered
[    0.904392] registered taskstats version 1
[    0.904430] Loading compiled-in X.509 certificates
[    0.905729] Key type ._fscrypt registered
[    0.905757] Key type .fscrypt registered
[    0.905775] Key type fscrypt-provisioning registered
[    0.916575] uart-pl011 fe201000.serial: there is not valid maps for 
state default
[    0.916834] uart-pl011 fe201000.serial: cts_event_workaround enabled
[    0.916957] fe201000.serial: ttyAMA0 at MMIO 0xfe201000 (irq = 21, 
base_baud = 0) is a PL011 rev2
[    2.214315] printk: console [ttyAMA0] enabled
[    2.228695] bcm2835-power bcm2835-power: Broadcom BCM2835 power 
domains driver
[    2.236930] mmc-bcm2835 fe300000.mmcnr: mmc_debug:0 mmc_debug2:0
[    2.242970] mmc-bcm2835 fe300000.mmcnr: DMA channel allocated
[    2.277785] of_cfs_init
[    2.280517] of_cfs_init: OK
[    2.301056] mmc1: queuing unknown CIS tuple 0x80 (2 bytes)
[    2.308225] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
[    2.312300] mmc0: SDHCI controller on fe340000.mmc [fe340000.mmc] 
using ADMA
[    2.315384] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
[    2.329501] Freeing unused kernel memory: 2560K
[    2.337101] mmc1: queuing unknown CIS tuple 0x80 (7 bytes)
[    2.344237] usb 1-1: new high-speed USB device number 2 using xhci_hcd
[    2.350925] Run /init as init process
[    2.354928] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
[    2.415357] Alpine Init 3.5.0-r0
[    2.421614] Loading boot drivers...
[    2.431309] mmc1: new high speed SDIO card at address 0001
[    2.442600] squashfs: version 4.0 (2009/01/31) Phillip Lougher
[    2.450043] Loading boot drivers: ok.
[    2.457543] Mounting root...
[    2.518933] usb 1-1: New USB device found, idVendor=2109, 
idProduct=3431, bcdDevice= 4.21
[    2.531298] usb 1-1: New USB device strings: Mfr=0, Product=1, 
SerialNumber=0
[    2.543436] usb 1-1: Product: USB2.0 Hub
[    2.564932] hub 1-1:1.0: USB hub found
[    2.570392] hub 1-1:1.0: 4 ports detected
[    8.066269] /dev/nfs: Can't open blockdev
[    8.072541] Mounting root: failed.
<<<

On Alpine nfs-utils has been installed and nfs + nfsmount rc-services 
have been added to default.

localhost:~$ rc-update |grep -i nfs
                   nfs |      default
              nfsmount |      default                    sysinit
localhost:~$
<<<

At this point I am not sure whether the nfs driver is missing within the 
default Alpine rpi aarch64 kernel or if I am doing something wrong rather.

Any help will be much appreciated.

Regards,
Pietro

---

From: Pietro Sammarco <[email-masked]>
Date: Sun, 21 Nov 2021 11:35:46 +0000

Hello,

I have added the following features to mkinitfs and rebuilt the 
initramfs, and although I am still unable to mount the root partition, 
the mount error has sightly changed to just "Mounting root: failed". Not 
very useful I am afraid.

Any idea? Has anybody else managed to netboot Apline aarch64 on the RPI 
4? Thanks

admin@gentoo ~ $ cat /zfs/netboot/node0/etc/mkinitfs/mkinitfs.conf
features="ata base cdrom ext4 keymap kms mmc nvme raid scsi usb virtio 
squashfs network dhcp nfs"
admin@gentoo ~ $
<<<

[    0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd083]
[    0.000000] Linux version 5.10.61-0-rpi4 
(buildozer@build-3-14-aarch64) (gcc (Alpine 10.3.1_git20210424) 10.3.1 
20210424, GNU ld (GNU Binutils) 2.35.2) #1-Alpine SMP PREEMPT Thu Aug 26 
22:38:20 UTC 2021
[    0.000000] random: fast init done
[    0.000000] Machine model: Raspberry Pi 4 Model B Rev 1.4
[    0.000000] efi: UEFI not found.
[    0.000000] Reserved memory: created CMA memory pool at 
0x000000002a800000, size 64 MiB
[    0.000000] OF: reserved mem: initialized node linux,cma, compatible 
id shared-dma-pool
[    0.000000] Zone ranges:
[    0.000000]   DMA      [mem 0x0000000000000000-0x000000003fffffff]
[    0.000000]   DMA32    [mem 0x0000000040000000-0x00000000ffffffff]
[    0.000000]   Normal   [mem 0x0000000100000000-0x00000001ffffffff]
[    0.000000] Movable zone start for each node
[    0.000000] Early memory node ranges
[    0.000000]   node   0: [mem 0x0000000000000000-0x000000003b3fffff]
[    0.000000]   node   0: [mem 0x0000000040000000-0x00000000fbffffff]
[    0.000000]   node   0: [mem 0x0000000100000000-0x00000001ffffffff]
[    0.000000] Initmem setup node 0 [mem 
0x0000000000000000-0x00000001ffffffff]
[    0.000000] percpu: Embedded 32 pages/cpu s91096 r8192 d31784 u131072
[    0.000000] Detected PIPT I-cache on CPU0
[    0.000000] CPU features: detected: Spectre-v2
[    0.000000] CPU features: detected: Spectre-v4
[    0.000000] CPU features: detected: ARM errata 1165522, 1319367, or 
1530923
[    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 
2028848
[    0.000000] Kernel command line: coherent_pool=1M 8250.nr_uarts=1 
snd_bcm2835.enable_compat_alsa=0 snd_bcm2835.enable_hdmi=1 
bcm2708_fb.fbwidth=0 bcm2708_fb.fbheight=0 bcm2708_fb.fbswap=1 
smsc95xx.macaddr=DC:A6:32:D6:35:2E vc_mem.mem_base=0x3ec00000 
vc_mem.mem_size=0x40000000  console=ttyAMA0,115200 console=tty1 
root=/dev/nfs nfsroot=172.12.1.57:/zfs/netboot/node0,vers=3,proto=tcp rw 
ip=dhcp rootfstype=nfs rootwait cgroup_memory=1 cgroup_enable=memory
[    0.000000] cgroup: Enabling memory control group subsystem
[    0.000000] Dentry cache hash table entries: 1048576 (order: 11, 
8388608 bytes, linear)
[    0.000000] Inode-cache hash table entries: 524288 (order: 10, 
4194304 bytes, linear)
[    0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
[    0.000000] software IO TLB: mapped [mem 
0x0000000037400000-0x000000003b400000] (64MB)
[    0.000000] Memory: 7927112K/8245248K available (10944K kernel code, 
1944K rwdata, 3944K rodata, 2560K init, 1251K bss, 252600K reserved, 
65536K cma-reserved)
[    0.000000] random: get_random_u64 called from 
__kmem_cache_create+0x28/0x4c0 with crng_init=1
[    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=4, Nodes=1
[    0.000000] rcu: Preemptible hierarchical RCU implementation.
[    0.000000] rcu:     RCU event tracing is enabled.
[    0.000000] rcu:     RCU restricting CPUs from NR_CPUS=256 to 
nr_cpu_ids=4.
[    0.000000]     Trampoline variant of Tasks RCU enabled.
[    0.000000]     Tracing variant of Tasks RCU enabled.
[    0.000000] rcu: RCU calculated value of scheduler-enlistment delay 
is 25 jiffies.
[    0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=4
[    0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
[    0.000000] GIC: Using split EOI/Deactivate mode
[    0.000000] arch_timer: cp15 timer(s) running at 54.00MHz (phys).
[    0.000000] clocksource: arch_sys_counter: mask: 0xffffffffffffff 
max_cycles: 0xc743ce346, max_idle_ns: 440795203123 ns
[    0.000002] sched_clock: 56 bits at 54MHz, resolution 18ns, wraps 
every 4398046511102ns
[    0.000114] Console: colour dummy device 80x25
[    0.000311] printk: console [tty1] enabled
[    0.000343] Calibrating delay loop (skipped), value calculated using 
timer frequency.. 108.00 BogoMIPS (lpj=216000)
[    0.000360] pid_max: default: 32768 minimum: 301
[    0.000455] LSM: Security Framework initializing
[    0.000603] Mount-cache hash table entries: 16384 (order: 5, 131072 
bytes, linear)
[    0.000669] Mountpoint-cache hash table entries: 16384 (order: 5, 
131072 bytes, linear)
[    0.002016] rcu: Hierarchical SRCU implementation.
[    0.002519] EFI services will not be available.
[    0.002752] smp: Bringing up secondary CPUs ...
[    0.003163] Detected PIPT I-cache on CPU1
[    0.003203] CPU1: Booted secondary processor 0x0000000001 [0x410fd083]
[    0.003672] Detected PIPT I-cache on CPU2
[    0.003691] CPU2: Booted secondary processor 0x0000000002 [0x410fd083]
[    0.004191] Detected PIPT I-cache on CPU3
[    0.004210] CPU3: Booted secondary processor 0x0000000003 [0x410fd083]
[    0.004270] smp: Brought up 1 node, 4 CPUs
[    0.004287] SMP: Total of 4 processors activated.
[    0.004296] CPU features: detected: 32-bit EL0 Support
[    0.004305] CPU features: detected: CRC32 instructions
[    0.004314] CPU features: detected: 32-bit EL1 Support
[    0.017700] CPU: All CPU(s) started at EL2
[    0.017738] alternatives: patching kernel code
[    0.018758] devtmpfs: initialized
[    0.023263] Enabled cp15_barrier support
[    0.023296] Enabled setend support
[    0.023584] clocksource: jiffies: mask: 0xffffffff max_cycles: 
0xffffffff, max_idle_ns: 7645041785100000 ns
[    0.023607] futex hash table entries: 1024 (order: 4, 65536 bytes, 
linear)
[    0.024981] pinctrl core: initialized pinctrl subsystem
[    0.026189] DMI not present or invalid.
[    0.026410] NET: Registered protocol family 16
[    0.027609] DMA: preallocated 1024 KiB GFP_KERNEL pool for atomic 
allocations
[    0.027719] DMA: preallocated 1024 KiB GFP_KERNEL|GFP_DMA pool for 
atomic allocations
[    0.028091] DMA: preallocated 1024 KiB GFP_KERNEL|GFP_DMA32 pool for 
atomic allocations
[    0.028151] audit: initializing netlink subsys (disabled)
[    0.028283] audit: type=2000 audit(0.028:1): state=initialized 
audit_enabled=0 res=1
[    0.029643] thermal_sys: Registered thermal governor 'step_wise'
[    0.029993] cpuidle: using governor menu
[    0.030114] hw-breakpoint: found 6 breakpoint and 4 watchpoint registers.
[    0.030192] ASID allocator initialised with 65536 entries
[    0.030327] Serial: AMBA PL011 UART driver
[    0.044779] bcm2835-mbox fe00b880.mailbox: mailbox enabled
[    0.052116] raspberrypi-firmware soc:firmware: Attached to firmware 
from 2021-08-03T18:14:56, variant start
[    0.056114] raspberrypi-firmware soc:firmware: Firmware hash is 
40787ee5905644f639a2a0f6e00ae12e517a2211
[    0.086779] bcm2835-dma fe007000.dma: DMA legacy API manager, 
dmachans=0x1
[    0.088807] vgaarb: loaded
[    0.089085] SCSI subsystem initialized
[    0.089251] usbcore: registered new interface driver usbfs
[    0.089287] usbcore: registered new interface driver hub
[    0.089338] usbcore: registered new device driver usb
[    0.089506] usb_phy_generic phy: supply vcc not found, using dummy 
regulator
[    0.090581] clocksource: Switched to clocksource arch_sys_counter
[    0.499976] VFS: Disk quotas dquot_6.6.0
[    0.500036] VFS: Dquot-cache hash table entries: 512 (order 0, 4096 
bytes)
[    0.500115] FS-Cache: Loaded
[    0.500250] CacheFiles: Loaded
[    0.507240] NET: Registered protocol family 2
[    0.507840] IP idents hash table entries: 131072 (order: 8, 1048576 
bytes, linear)
[    0.510314] tcp_listen_portaddr_hash hash table entries: 4096 (order: 
4, 65536 bytes, linear)
[    0.510367] TCP established hash table entries: 65536 (order: 7, 
524288 bytes, linear)
[    0.510555] TCP bind hash table entries: 65536 (order: 8, 1048576 
bytes, linear)
[    0.511513] TCP: Hash tables configured (established 65536 bind 65536)
[    0.511721] UDP hash table entries: 4096 (order: 5, 131072 bytes, linear)
[    0.511782] UDP-Lite hash table entries: 4096 (order: 5, 131072 
bytes, linear)
[    0.512002] NET: Registered protocol family 1
[    0.512478] RPC: Registered named UNIX socket transport module.
[    0.512490] RPC: Registered udp transport module.
[    0.512498] RPC: Registered tcp transport module.
[    0.512505] RPC: Registered tcp NFSv4.1 backchannel transport module.
[    0.512519] PCI: CLS 0 bytes, default 64
[    0.512650] Trying to unpack rootfs image as initramfs...
[    0.670793] Freeing initrd memory: 5564K
[    0.671662] hw perfevents: enabled with armv8_cortex_a72 PMU driver, 
7 counters available
[    0.671812] kvm [1]: IPA Size Limit: 44 bits
[    0.672290] kvm [1]: vgic interrupt IRQ9
[    0.672407] kvm [1]: Hyp mode initialized successfully
[    0.673495] Initialise system trusted keyrings
[    0.673745] workingset: timestamp_bits=46 max_order=21 bucket_order=0
[    0.676353] zbud: loaded
[    0.677164] FS-Cache: Netfs 'nfs' registered for caching
[    0.677495] NFS: Registering the id_resolver key type
[    0.677518] Key type id_resolver registered
[    0.677526] Key type id_legacy registered
[    0.677585] nfs4filelayout_init: NFSv4 File Layout Driver Registering...
[    0.677595] nfs4flexfilelayout_init: NFSv4 Flexfile Layout Driver 
Registering...
[    0.678117] Key type asymmetric registered
[    0.678127] Asymmetric key parser 'x509' registered
[    0.678164] Block layer SCSI generic (bsg) driver version 0.4 loaded 
(major 249)
[    0.678289] io scheduler mq-deadline registered
[    0.678300] io scheduler kyber registered
[    0.680112] brcm-pcie fd500000.pcie: host bridge /scb/pcie@7d500000 
ranges:
[    0.680138] brcm-pcie fd500000.pcie:   No bus range found for 
/scb/pcie@7d500000, using [bus 00-ff]
[    0.680170] brcm-pcie fd500000.pcie:      MEM 
0x0600000000..0x063fffffff -> 0x00c0000000
[    0.680204] brcm-pcie fd500000.pcie:   IB MEM 
0x0000000000..0x00bfffffff -> 0x0400000000
[    0.744641] brcm-pcie fd500000.pcie: link up, 5.0 GT/s PCIe x1 (SSC)
[    0.744844] brcm-pcie fd500000.pcie: PCI host bridge to bus 0000:00
[    0.744858] pci_bus 0000:00: root bus resource [bus 00-ff]
[    0.744869] pci_bus 0000:00: root bus resource [mem 
0x600000000-0x63fffffff] (bus address [0xc0000000-0xffffffff])
[    0.744912] pci 0000:00:00.0: [14e4:2711] type 01 class 0x060400
[    0.745014] pci 0000:00:00.0: PME# supported from D0 D3hot
[    0.746484] pci 0000:00:00.0: bridge configuration invalid ([bus 
00-00]), reconfiguring
[    0.746695] pci 0000:01:00.0: [1106:3483] type 00 class 0x0c0330
[    0.746786] pci 0000:01:00.0: reg 0x10: [mem 0x00000000-0x00000fff 64bit]
[    0.747063] pci 0000:01:00.0: PME# supported from D0 D3hot
[    0.759862] pci_bus 0000:01: busn_res: [bus 01-ff] end is updated to 01
[    0.759890] pci 0000:00:00.0: BAR 8: assigned [mem 
0x600000000-0x6000fffff]
[    0.759903] pci 0000:01:00.0: BAR 0: assigned [mem 
0x600000000-0x600000fff 64bit]
[    0.759925] pci 0000:00:00.0: PCI bridge to [bus 01]
[    0.759938] pci 0000:00:00.0:   bridge window [mem 
0x600000000-0x6000fffff]
[    0.760250] bcm2708_fb soc:fb: Unable to determine number of FBs. 
Disabling driver.
[    0.760270] bcm2708_fb: probe of soc:fb failed with error -2
[    0.762275] Serial: 8250/16550 driver, 1 ports, IRQ sharing enabled
[    0.763701] iproc-rng200 fe104000.rng: hwrng registered
[    0.763888] vc-mem: phys_addr:0x00000000 mem_base=0x3ec00000 
mem_size:0x40000000(1024 MiB)
[    0.764532] gpiomem-bcm2835 fe200000.gpiomem: Initialised: Registers 
at 0xfe200000
[    0.764752] cacheinfo: Unable to detect cache hierarchy for CPU 0
[    0.770142] brd: module loaded
[    0.776421] loop: module loaded
[    0.777274] Loading iSCSI transport class v2.0-870.
[    0.779307] libphy: Fixed MDIO Bus: probed
[    0.780234] bcmgenet fd580000.ethernet: GENET 5.0 EPHY: 0x0000
[    0.790632] libphy: bcmgenet MII bus: probed
[    0.838800] unimac-mdio unimac-mdio.-19: Broadcom UniMAC MDIO bus
[    0.840073] usbcore: registered new interface driver r8152
[    0.840177] usbcore: registered new interface driver lan78xx
[    0.840265] usbcore: registered new interface driver smsc95xx
[    0.887788] pci 0000:00:00.0: enabling device (0000 -> 0002)
[    0.887980] xhci_hcd 0000:01:00.0: xHCI Host Controller
[    0.888023] xhci_hcd 0000:01:00.0: new USB bus registered, assigned 
bus number 1
[    0.888749] xhci_hcd 0000:01:00.0: hcc params 0x002841eb hci version 
0x100 quirks 0x0000060000000890
[    0.890010] usb usb1: New USB device found, idVendor=1d6b, 
idProduct=0002, bcdDevice= 5.10
[    0.890042] usb usb1: New USB device strings: Mfr=3, Product=2, 
SerialNumber=1
[    0.890065] usb usb1: Product: xHCI Host Controller
[    0.890086] usb usb1: Manufacturer: Linux 5.10.61-0-rpi4 xhci-hcd
[    0.890107] usb usb1: SerialNumber: 0000:01:00.0
[    0.890858] hub 1-0:1.0: USB hub found
[    0.890981] hub 1-0:1.0: 1 port detected
[    0.891632] xhci_hcd 0000:01:00.0: xHCI Host Controller
[    0.891669] xhci_hcd 0000:01:00.0: new USB bus registered, assigned 
bus number 2
[    0.891704] xhci_hcd 0000:01:00.0: Host supports USB 3.0 SuperSpeed
[    0.892127] usb usb2: New USB device found, idVendor=1d6b, 
idProduct=0003, bcdDevice= 5.10
[    0.892155] usb usb2: New USB device strings: Mfr=3, Product=2, 
SerialNumber=1
[    0.892179] usb usb2: Product: xHCI Host Controller
[    0.892199] usb usb2: Manufacturer: Linux 5.10.61-0-rpi4 xhci-hcd
[    0.892219] usb usb2: SerialNumber: 0000:01:00.0
[    0.892894] hub 2-0:1.0: USB hub found
[    0.892983] hub 2-0:1.0: 4 ports detected
[    0.894438] dwc_otg: version 3.00a 10-AUG-2012 (platform bus)
[    0.895221] usbcore: registered new interface driver uas
[    0.895333] usbcore: registered new interface driver usb-storage
[    0.895593] mousedev: PS/2 mouse device common for all mice
[    0.897763] bcm2835-wdt bcm2835-wdt: Broadcom BCM2835 watchdog timer
[    0.901080] sdhci: Secure Digital Host Controller Interface driver
[    0.901118] sdhci: Copyright(c) Pierre Ossman
[    0.901762] mmc-bcm2835 fe300000.mmcnr: could not get clk, deferring 
probe
[    0.902263] sdhci-pltfm: SDHCI platform and OF driver helper
[    0.905022] ledtrig-cpu: registered to indicate activity on CPUs
[    0.905520] hid: raw HID events driver (C) Jiri Kosina
[    0.905726] usbcore: registered new interface driver usbhid
[    0.905748] usbhid: USB HID core driver
[    0.906101] ashmem: initialized
[    0.913986] Initializing XFRM netlink socket
[    0.914139] Key type dns_resolver registered
[    0.915618] registered taskstats version 1
[    0.915659] Loading compiled-in X.509 certificates
[    0.916168] Key type ._fscrypt registered
[    0.916193] Key type .fscrypt registered
[    0.916211] Key type fscrypt-provisioning registered
[    0.927098] uart-pl011 fe201000.serial: there is not valid maps for 
state default
[    0.927355] uart-pl011 fe201000.serial: cts_event_workaround enabled
[    0.927466] fe201000.serial: ttyAMA0 at MMIO 0xfe201000 (irq = 21, 
base_baud = 0) is a PL011 rev2
[    2.226237] printk: console [ttyAMA0] enabled
[    2.237641] bcm2835-power bcm2835-power: Broadcom BCM2835 power 
domains driver
[    2.245902] mmc-bcm2835 fe300000.mmcnr: mmc_debug:0 mmc_debug2:0
[    2.251944] mmc-bcm2835 fe300000.mmcnr: DMA channel allocated
[    2.288871] of_cfs_init
[    2.291584] of_cfs_init: OK
[    2.310814] mmc1: queuing unknown CIS tuple 0x80 (2 bytes)
[    2.317940] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
[    2.322111] mmc0: SDHCI controller on fe340000.mmc [fe340000.mmc] 
using ADMA
[    2.325250] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
[    2.339361] Freeing unused kernel memory: 2560K
[    2.347848] mmc1: queuing unknown CIS tuple 0x80 (7 bytes)
[    2.355092] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
[    2.360658] usb 1-1: new high-speed USB device number 2 using xhci_hcd
[    2.360789] Run /init as init process
[    2.429045] mmc1: new high speed SDIO card at address 0001
[    2.429102] Alpine Init 3.5.0-r0
[    2.439526] Loading boot drivers...
[    2.459739] squashfs: version 4.0 (2009/01/31) Phillip Lougher
[    2.466835] Loading boot drivers: ok.
[    2.474267] Mounting root...
[    2.521335] usb 1-1: New USB device found, idVendor=2109, 
idProduct=3431, bcdDevice= 4.21
[    2.530417] usb 1-1: New USB device strings: Mfr=0, Product=1, 
SerialNumber=0
[    2.541040] usb 1-1: Product: USB2.0 Hub
[    2.550853] hub 1-1:1.0: USB hub found
[    2.557190] hub 1-1:1.0: 4 ports detected
[    8.083226] Mounting root: failed.
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cmdline.txt

vswitch0:~$ cat /var/tftpboot/node0/cmdline.txt
console=serial0,115200 console=tty1 root=/dev/nfs 
nfsroot=172.12.1.57:/zfs/netboot/node0,vers=3,proto=tcp rw ip=dhcp 
rootfstype=nfs rootwait cgroup_memory=1 cgroup_enable=memory
vswitch0:~$
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