Pi Zero 2 USB boot stuck in a boot loop

[Martin]

I know it's still early days with the ne w Pi Zero 2, but I picked up a couple and have been seeing how they work with the clusterHAT.

 I've got two Pi Zero 2s, but for testing I've just been populating the clusterHAT with a single Pi to avoid hitting power issues whilst trying to get things working. So far, running the Pi off an SD card has worked smooth enough, the issues come when trying to USB boot without an SD card. 

Currently the Pi is stuck on boot. The initial recognition is good

==> /var/log/kern.log <==

Oct 31 22:43:05 cbridge kernel: [ 2152.979862] usb 1-1.4.4: new high-speed USB device number 7 using xhci_hcd

Oct 31 22:43:05 cbridge kernel: [ 2153.110165] usb 1-1.4.4: config index 0 descriptor too short (expected 55, got 32)

Oct 31 22:43:05 cbridge kernel: [ 2153.110470] usb 1-1.4.4: New USB device found, idVendor=0a5c, idProduct=2764, bcdDevice= 0.00

Oct 31 22:43:05 cbridge kernel: [ 2153.110488] usb 1-1.4.4: New USB device strings: Mfr=1, Product=2, SerialNumber=0

Oct 31 22:43:05 cbridge kernel: [ 2153.110504] usb 1-1.4.4: Product: BCM2710 Boot

Oct 31 22:43:05 cbridge kernel: [ 2153.110518] usb 1-1.4.4: Manufacturer: Broadcom

 but after that it keeps repeating indefinitely

==> /var/log/daemon.log <==

Oct 31 22:43:05 cbridge rpiboot[458]: Loading: /var/lib/clusterctrl/boot//bootcode.bin

Oct 31 22:43:05 cbridge rpiboot[458]: Device located successfully

Oct 31 22:43:05 cbridge rpiboot[458]: libusb: error [udev_hotplug_event] ignoring udev action bind

Oct 31 22:43:06 cbridge rpiboot[458]: Initialised device correctly

Oct 31 22:43:06 cbridge rpiboot[458]: Found serial number 0

Oct 31 22:43:06 cbridge rpiboot[458]: Sending bootcode.bin

Oct 31 22:43:06 cbridge rpiboot[458]: libusb_bulk_transfer sent 24 bytes; returned 0

Oct 31 22:43:06 cbridge rpiboot[458]: Writing 52304 bytes

Oct 31 22:43:06 cbridge rpiboot[458]: libusb_bulk_transfer sent 52304 bytes; returned 0

Oct 31 22:43:10 cbridge rpiboot[458]: Failed : 0x0

Oct 31 22:43:11 cbridge rpiboot[458]: Waiting for BCM2835/6/7/2711...

Oct 31 22:43:11 cbridge rpiboot[458]: Loading: /var/lib/clusterctrl/boot//bootcode.bin

Oct 31 22:43:11 cbridge rpiboot[458]: Device located successfully

Oct 31 22:43:12 cbridge rpiboot[458]: Initialised device correctly

Oct 31 22:43:12 cbridge rpiboot[458]: Found serial number 0

Oct 31 22:43:12 cbridge rpiboot[458]: Sending bootcode.bin

Oct 31 22:43:13 cbridge rpiboot[458]: Failed control transfer (-7,24)

Oct 31 22:43:13 cbridge rpiboot[458]: Failed to write correct length, returned -7

Oct 31 22:43:14 cbridge rpiboot[458]: Waiting for BCM2835/6/7/2711...

Oct 31 22:43:14 cbridge rpiboot[458]: Loading: /var/lib/clusterctrl/boot//bootcode.bin

Oct 31 22:43:14 cbridge rpiboot[458]: Device located successfully

Oct 31 22:43:15 cbridge rpiboot[458]: Initialised device correctly

Oct 31 22:43:15 cbridge rpiboot[458]: Found serial number 0

Oct 31 22:43:15 cbridge rpiboot[458]: Sending bootcode.bin

Oct 31 22:43:16 cbridge rpiboot[458]: Failed control transfer (-7,24)

Oct 31 22:43:16 cbridge rpiboot[458]: Failed to write correct length, returned -7

Oct 31 22:43:17 cbridge rpiboot[458]: Waiting for BCM2835/6/7/2711...

 

etc.

According to a comment here https://forums.raspberrypi.com/viewtopic.php?p=1931185#p1931185 it's possible but it needs a different initrd, so I've attempted to make the same change by updating the config.txt for the p1 nfs to include 

[pi02]

initramfs initramfs7.img

but that doesn't seem to have made any difference.

I've also tried booting a zero from an SD and doing update-initiramfs to build a new img and use that.

[pi02]

initramfs initrd.img-5.10.63-v7+ followkernel

None of this seems to make a difference to the errors I'm getting, so there may be something else I'm missing. If anyone is able to shine some light on what might be up, that would be a real help.

Setup for reference:

CBRIDGE - Raspberry Pi 4b 8gb - Booted via USB with a 160gb SSD

ClusterHAT v2.4 with 1x Raspberry Pi Zero 2 W installed (no SD card)

3A power supply 

Thanks,

Martin

[Martin]

Update to this. I've tried out my second Pi Zero 2 W, and that one seems to not have the issue and gets a little further through the boot process, so I'm not quite sure what is up with the pi that gets stuck in the boot loop.

Here is the boot output for my second Pi Zero 2 W

==> /var/log/daemon.log <==

Nov  1 21:39:38 cbridge rpiboot[480]: libusb: error [udev_hotplug_event] ignoring udev action bind

Nov  1 21:39:38 cbridge rpiboot[480]: Failed to open the requested device

Nov  1 21:39:38 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//bootcode.bin

Nov  1 21:39:38 cbridge rpiboot[480]: Device located successfully

Nov  1 21:39:39 cbridge rpiboot[480]: Initialised device correctly

Nov  1 21:39:39 cbridge rpiboot[480]: Found serial number 1

Nov  1 21:39:39 cbridge rpiboot[480]: Second stage boot server

Nov  1 21:39:39 cbridge rpiboot[480]: Received message GetFileSize: autoboot.txt

Nov  1 21:39:39 cbridge rpiboot[480]: libusb_bulk_transfer sent 0 bytes; returned 0

Nov  1 21:39:39 cbridge rpiboot[480]: Cannot open file autoboot.txt

Nov  1 21:39:39 cbridge rpiboot[480]: Received message GetFileSize: config.txt

Nov  1 21:39:39 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//1-1.4.4/config.txt

Nov  1 21:39:39 cbridge rpiboot[480]: File size = 2092 bytes

Nov  1 21:39:39 cbridge rpiboot[480]: Received message ReadFile: config.txt

Nov  1 21:39:39 cbridge rpiboot[480]: File read: config.txt

Nov  1 21:39:39 cbridge rpiboot[480]: libusb_bulk_transfer sent 2092 bytes; returned 0

Nov  1 21:39:39 cbridge rpiboot[480]: Received message GetFileSize: recovery.elf

Nov  1 21:39:39 cbridge rpiboot[480]: libusb_bulk_transfer sent 0 bytes; returned 0

Nov  1 21:39:39 cbridge rpiboot[480]: Cannot open file recovery.elf

Nov  1 21:39:39 cbridge rpiboot[480]: Received message GetFileSize: start.elf

Nov  1 21:39:39 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//1-1.4.4/start.elf

Nov  1 21:39:39 cbridge rpiboot[480]: File size = 2965632 bytes

Nov  1 21:39:39 cbridge rpiboot[480]: Received message ReadFile: start.elf

Nov  1 21:39:39 cbridge rpiboot[480]: File read: start.elf

Nov  1 21:39:42 cbridge rpiboot[480]: libusb_bulk_transfer sent 2965632 bytes; returned 0

Nov  1 21:39:42 cbridge rpiboot[480]: Received message GetFileSize: fixup.dat

Nov  1 21:39:42 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//1-1.4.4/fixup.dat

Nov  1 21:39:42 cbridge rpiboot[480]: File size = 7279 bytes

Nov  1 21:39:42 cbridge rpiboot[480]: Received message ReadFile: fixup.dat

Nov  1 21:39:42 cbridge rpiboot[480]: File read: fixup.dat

Nov  1 21:39:42 cbridge rpiboot[480]: libusb_bulk_transfer sent 7279 bytes; returned 0

Nov  1 21:39:42 cbridge rpiboot[480]: Received message GetFileSize: recovery.elf

Nov  1 21:39:42 cbridge rpiboot[480]: libusb_bulk_transfer sent 0 bytes; returned 0

Nov  1 21:39:42 cbridge rpiboot[480]: Cannot open file recovery.elf

Nov  1 21:39:42 cbridge rpiboot[480]: Received message GetFileSize: config.txt

Nov  1 21:39:42 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//1-1.4.4/config.txt

Nov  1 21:39:42 cbridge rpiboot[480]: File size = 2092 bytes

Nov  1 21:39:42 cbridge rpiboot[480]: Received message ReadFile: config.txt

Nov  1 21:39:42 cbridge rpiboot[480]: File read: config.txt

Nov  1 21:39:42 cbridge rpiboot[480]: libusb_bulk_transfer sent 2092 bytes; returned 0

Nov  1 21:39:42 cbridge rpiboot[480]: Received message GetFileSize: dt-blob.bin

Nov  1 21:39:42 cbridge rpiboot[480]: libusb_bulk_transfer sent 0 bytes; returned 0

Nov  1 21:39:42 cbridge rpiboot[480]: Cannot open file dt-blob.bin

Nov  1 21:39:42 cbridge rpiboot[480]: Received message GetFileSize: recovery.elf

Nov  1 21:39:42 cbridge rpiboot[480]: libusb_bulk_transfer sent 0 bytes; returned 0

Nov  1 21:39:42 cbridge rpiboot[480]: Cannot open file recovery.elf

Nov  1 21:39:42 cbridge rpiboot[480]: Received message GetFileSize: config.txt

Nov  1 21:39:42 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//1-1.4.4/config.txt

Nov  1 21:39:42 cbridge rpiboot[480]: File size = 2092 bytes

Nov  1 21:39:42 cbridge rpiboot[480]: Received message ReadFile: config.txt

Nov  1 21:39:42 cbridge rpiboot[480]: File read: config.txt

Nov  1 21:39:42 cbridge rpiboot[480]: libusb_bulk_transfer sent 2092 bytes; returned 0

Nov  1 21:39:43 cbridge rpiboot[480]: Received message GetFileSize: bootcfg.txt

Nov  1 21:39:43 cbridge rpiboot[480]: libusb_bulk_transfer sent 0 bytes; returned 0

Nov  1 21:39:43 cbridge rpiboot[480]: Cannot open file bootcfg.txt

Nov  1 21:39:43 cbridge rpiboot[480]: Received message GetFileSize: initramfs7.img

Nov  1 21:39:43 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//1-1.4.4/initramfs7.img

Nov  1 21:39:43 cbridge rpiboot[480]: File size = 5774464 bytes

Nov  1 21:39:43 cbridge rpiboot[480]: Received message ReadFile: initramfs7.img

Nov  1 21:39:43 cbridge rpiboot[480]: File read: initramfs7.img

Nov  1 21:39:49 cbridge rpiboot[480]: libusb_bulk_transfer sent 5774464 bytes; returned 0

Nov  1 21:39:49 cbridge rpiboot[480]: Received message GetFileSize: bcm2710-rpi-zero-2.dtb

Nov  1 21:39:49 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//1-1.4.4/bcm2710-rpi-zero-2.dtb

Nov  1 21:39:49 cbridge rpiboot[480]: File size = 28100 bytes

Nov  1 21:39:49 cbridge rpiboot[480]: Received message ReadFile: bcm2710-rpi-zero-2.dtb

Nov  1 21:39:49 cbridge rpiboot[480]: File read: bcm2710-rpi-zero-2.dtb

Nov  1 21:39:49 cbridge rpiboot[480]: libusb_bulk_transfer sent 28100 bytes; returned 0

Nov  1 21:39:49 cbridge rpiboot[480]: Received message GetFileSize: overlays/overlay_map.dtb

Nov  1 21:39:49 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//1-1.4.4/overlays/overlay_map.dtb

Nov  1 21:39:49 cbridge rpiboot[480]: File size = 1667 bytes

Nov  1 21:39:49 cbridge rpiboot[480]: Received message ReadFile: overlays/overlay_map.dtb

Nov  1 21:39:49 cbridge rpiboot[480]: File read: overlays/overlay_map.dtb

Nov  1 21:39:49 cbridge rpiboot[480]: libusb_bulk_transfer sent 1667 bytes; returned 0

Nov  1 21:39:49 cbridge rpiboot[480]: Received message GetFileSize: config.txt

Nov  1 21:39:49 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//1-1.4.4/config.txt

Nov  1 21:39:49 cbridge rpiboot[480]: File size = 2092 bytes

Nov  1 21:39:49 cbridge rpiboot[480]: Received message ReadFile: config.txt

Nov  1 21:39:49 cbridge rpiboot[480]: File read: config.txt

Nov  1 21:39:49 cbridge rpiboot[480]: libusb_bulk_transfer sent 2092 bytes; returned 0

Nov  1 21:39:49 cbridge rpiboot[480]: Received message GetFileSize: overlays/dwc2.dtbo

Nov  1 21:39:49 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//1-1.4.4/overlays/dwc2.dtbo

Nov  1 21:39:49 cbridge rpiboot[480]: File size = 801 bytes

Nov  1 21:39:49 cbridge rpiboot[480]: Received message ReadFile: overlays/dwc2.dtbo

Nov  1 21:39:49 cbridge rpiboot[480]: File read: overlays/dwc2.dtbo

Nov  1 21:39:49 cbridge rpiboot[480]: libusb_bulk_transfer sent 801 bytes; returned 0

Nov  1 21:39:49 cbridge rpiboot[480]: Received message GetFileSize: cmdline.txt

Nov  1 21:39:49 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//1-1.4.4/cmdline.txt

Nov  1 21:39:49 cbridge rpiboot[480]: File size = 216 bytes

Nov  1 21:39:49 cbridge rpiboot[480]: Received message ReadFile: cmdline.txt

Nov  1 21:39:49 cbridge rpiboot[480]: File read: cmdline.txt

Nov  1 21:39:49 cbridge rpiboot[480]: libusb_bulk_transfer sent 216 bytes; returned 0

Nov  1 21:39:49 cbridge rpiboot[480]: Received message GetFileSize: recovery8.img

Nov  1 21:39:49 cbridge rpiboot[480]: libusb_bulk_transfer sent 0 bytes; returned 0

Nov  1 21:39:49 cbridge rpiboot[480]: Cannot open file recovery8.img

Nov  1 21:39:49 cbridge rpiboot[480]: Received message GetFileSize: recovery8-32.img

Nov  1 21:39:49 cbridge rpiboot[480]: libusb_bulk_transfer sent 0 bytes; returned 0

Nov  1 21:39:49 cbridge rpiboot[480]: Cannot open file recovery8-32.img

Nov  1 21:39:49 cbridge rpiboot[480]: Received message GetFileSize: recovery7.img

Nov  1 21:39:49 cbridge rpiboot[480]: libusb_bulk_transfer sent 0 bytes; returned 0

Nov  1 21:39:49 cbridge rpiboot[480]: Cannot open file recovery7.img

Nov  1 21:39:49 cbridge rpiboot[480]: Received message GetFileSize: recovery.img

Nov  1 21:39:49 cbridge rpiboot[480]: libusb_bulk_transfer sent 0 bytes; returned 0

Nov  1 21:39:49 cbridge rpiboot[480]: Cannot open file recovery.img

Nov  1 21:39:49 cbridge rpiboot[480]: Received message GetFileSize: kernel8.img

Nov  1 21:39:49 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//1-1.4.4/kernel8.img

Nov  1 21:39:49 cbridge rpiboot[480]: File size = 7905972 bytes

Nov  1 21:39:49 cbridge rpiboot[480]: Received message GetFileSize: kernel8-32.img

Nov  1 21:39:49 cbridge rpiboot[480]: libusb_bulk_transfer sent 0 bytes; returned 0

Nov  1 21:39:49 cbridge rpiboot[480]: Cannot open file kernel8-32.img

Nov  1 21:39:49 cbridge rpiboot[480]: Received message GetFileSize: kernel7.img

Nov  1 21:39:49 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//1-1.4.4/kernel7.img

Nov  1 21:39:49 cbridge rpiboot[480]: File size = 6359096 bytes

Nov  1 21:39:49 cbridge rpiboot[480]: Received message GetFileSize: armstub8-32.bin

Nov  1 21:39:49 cbridge rpiboot[480]: libusb_bulk_transfer sent 0 bytes; returned 0

Nov  1 21:39:49 cbridge rpiboot[480]: Cannot open file armstub8-32.bin

Nov  1 21:39:49 cbridge rpiboot[480]: Received message GetFileSize: kernel7.img

Nov  1 21:39:49 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//1-1.4.4/kernel7.img

Nov  1 21:39:49 cbridge rpiboot[480]: File size = 6359096 bytes

Nov  1 21:39:49 cbridge rpiboot[480]: Received message ReadFile: kernel7.img

Nov  1 21:39:49 cbridge rpiboot[480]: File read: kernel7.img

Nov  1 21:39:55 cbridge rpiboot[480]: libusb_bulk_transfer sent 6359096 bytes; returned 0

Nov  1 21:39:55 cbridge rpiboot[480]: Received message Done: kernel7.img

Nov  1 21:39:55 cbridge rpiboot[480]: Second stage boot server done

Nov  1 21:39:56 cbridge rpiboot[480]: Waiting for BCM2835/6/7/2711...

Nov  1 21:39:56 cbridge rpiboot[480]: Loading: /var/lib/clusterctrl/boot//bootcode.bin

Nov  1 21:39:56 cbridge rpiboot[480]: Device located successfully

Nov  1 21:39:57 cbridge rpiboot[480]: Initialised device correctly

Nov  1 21:39:57 cbridge rpiboot[480]: Found serial number 1

Nov  1 21:39:57 cbridge rpiboot[480]: Second stage boot server

This one seems to get stuck on Second stage boot server after loading kernel7.img 

I've tried a couple of things like including bcm2710-rpi-zero-2.dtb and using the latest kernel7.img but beyond that I don't have many ideas

I'll keep prodding at things, but I am far from an expert in any of this 

[David Tenney]

Thanks for providing this. I am stuck with the original loop that you posted as well. Keep us informed on your progress.

[Martin]

Here's another update. I was at a bit of a loss for a while because from what i could tell, everything was working from the USBBOOT side of things, and it was successfully starting the kernel on the Zero 2, the green LED would come on, but i would never get anything in the logs.

So i invested in a USB to serial cable to to see if i could get anything from the console on the zero 2 that way.

The good news. I see logs! the bad news is that when the kernel calls init there is a kernel panic :(
Here's the last output:

[   19.042672] Freeing unused kernel memory: 1024K

[   19.050014] Run /init as init process

[   20.328417] process '/usr/bin/ipconfig' started with executable stack

[   20.650701] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000200

[   20.662439] CPU: 2 PID: 1 Comm: init Not tainted 5.10.76-v7+ #1475

[   20.670850] Hardware name: BCM2835

[   20.676418] Backtrace:

[   20.680995] [<809f2b70>] (dump_backtrace) from [<809f2f00>] (show_stack+0x20/0x24)

[   20.693130]  r7:ffffffff r6:00000000 r5:60000093 r4:80fe5e70

[   20.701252] [<809f2ee0>] (show_stack) from [<809f7114>] (dump_stack+0xcc/0xf8)

[   20.711071] [<809f7048>] (dump_stack) from [<809f32d4>] (panic+0x130/0x33c)

[   20.720625]  r10:000000f8 r9:00000000 r8:80100204 r7:ffffe000 r6:80cfa160 r5:00000000

[   20.733607]  r4:81049488 r3:00000001

[   20.739804] [<809f31a4>] (panic) from [<801240fc>] (do_exit+0xb7c/0xb88)

[   20.749301]  r3:00000001 r2:8151c004 r1:00000200 r0:80cfa160

[   20.757768]  r7:ffffe000

[   20.763018] [<80123580>] (do_exit) from [<801241a4>] (do_group_exit+0x50/0xe0)

[   20.773204]  r7:000000f8

[   20.778591] [<80124154>] (do_group_exit) from [<80124254>] (__wake_up_parent+0x0/0x2c)

[   20.792456]  r7:000000f8 r6:00000000 r5:000d5294 r4:00000004

[   20.801126] [<80124234>] (sys_exit_group) from [<80100040>] (ret_fast_syscall+0x0/0x28)

[   20.814993] Exception stack(0x8151bfa8 to 0x8151bff0)

[   20.823030] bfa0:                   00000004 000d5294 00000002 00000000 00000002 00000002

[   20.837257] bfc0: 00000004 000d5294 00000000 000000f8 00000002 00000000 76fd9000 000d518c

[   20.851491] bfe0: 000d4b00 7eb4ea18 0005b890 76ed5934

[   20.859605] CPU0: stopping

[   20.865280] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.10.76-v7+ #1475

[   20.874981] Hardware name: BCM2835

[   20.881307] Backtrace:

[   20.886635] [<809f2b70>] (dump_backtrace) from [<809f2f00>] (show_stack+0x20/0x24)

[   20.900123]  r7:ffffffff r6:00000000 r5:60000193 r4:80fe5e70

[   20.908863] [<809f2ee0>] (show_stack) from [<809f7114>] (dump_stack+0xcc/0xf8)

[   20.919229] [<809f7048>] (dump_stack) from [<8010e4f8>] (do_handle_IPI+0x30c/0x340)

[   20.932799]  r10:80cfc9fc r9:80f00000 r8:814de000 r7:00000001 r6:1ab66000 r5:00000000

[   20.946597]  r4:81049380 r3:0a28a839

[   20.953105] [<8010e1ec>] (do_handle_IPI) from [<8010e554>] (ipi_handler+0x28/0x30)

[   20.966556]  r9:80f00000 r8:814de000 r7:00000001 r6:1ab66000 r5:00000015 r4:814e1380

[   20.980312] [<8010e52c>] (ipi_handler) from [<8018bd10>] (handle_percpu_devid_fasteoi_ipi+0x80/0x154)

[   20.995653] [<8018bc90>] (handle_percpu_devid_fasteoi_ipi) from [<80184d2c>] (generic_handle_irq+0x44/0x54)

[   21.011723]  r7:00000001 r6:814dcb18 r5:80fe60e4 r4:9c8000c0

[   21.020634] [<80184ce8>] (generic_handle_irq) from [<80677d58>] (bcm2836_arm_irqchip_handle_ipi+0xa8/0xc8)

[   21.036853] [<80677cb0>] (bcm2836_arm_irqchip_handle_ipi) from [<80184d2c>] (generic_handle_irq+0x44/0x54)

[   21.053217]  r7:00000001 r6:00000000 r5:00000000 r4:80e91d90

[   21.062275] [<80184ce8>] (generic_handle_irq) from [<8018548c>] (__handle_domain_irq+0x6c/0xc4)

[   21.077746] [<80185420>] (__handle_domain_irq) from [<801012c8>] (bcm2836_arm_irqchip_handle_irq+0x60/0x64)

[   21.094378]  r9:80f00000 r8:00000001 r7:80f01f04 r6:ffffffff r5:60000013 r4:80108874

[   21.109030] [<80101268>] (bcm2836_arm_irqchip_handle_irq) from [<80100abc>] (__irq_svc+0x5c/0x7c)

[   21.124971] Exception stack(0x80f01ed0 to 0x80f01f18)

[   21.133537] 1ec0:                                     00000000 00003a80 9b9f9344 80119040

[   21.148550] 1ee0: ffffe000 80f05058 80f050a0 00000001 00000001 8103183f 80cfc9fc 80f01f2c

[   21.163471] 1f00: 80f01f30 80f01f20 80108870 80108874 60000013 ffffffff

[   21.173549] [<8010882c>] (arch_cpu_idle) from [<80a01bc8>] (default_idle_call+0x4c/0x118)

[   21.188492] [<80a01b7c>] (default_idle_call) from [<8015647c>] (do_idle+0x118/0x168)

[   21.202991] [<80156364>] (do_idle) from [<801567a0>] (cpu_startup_entry+0x28/0x30)

[   21.217345]  r10:9bfffa40 r9:80e52a58 r8:00000000 r7:80e52a58 r6:00000001 r5:80f05008

[   21.232029]  r4:000000d9 r3:80e87284

[   21.238938] [<80156778>] (cpu_startup_entry) from [<809fac00>] (rest_init+0xbc/0xc4)

[   21.253328] [<809fab44>] (rest_init) from [<80e00aa0>] (arch_call_rest_init+0x18/0x1c)

[   21.267887]  r5:80f05008 r4:81049068

[   21.274690] [<80e00a88>] (arch_call_rest_init) from [<80e01068>] (start_kernel+0x54c/0x580)

[   21.289619] [<80e00b1c>] (start_kernel) from [<00000000>] (0x0)

[   21.298949] CPU1: stopping

[   21.304900] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.10.76-v7+ #1475

[   21.314860] Hardware name: BCM2835

[   21.321459] Backtrace:

[   21.326991] [<809f2b70>] (dump_backtrace) from [<809f2f00>] (show_stack+0x20/0x24)

[   21.340785]  r7:ffffffff r6:00000000 r5:60000193 r4:80fe5e70

[   21.349601] [<809f2ee0>] (show_stack) from [<809f7114>] (dump_stack+0xcc/0xf8)

[   21.360018] [<809f7048>] (dump_stack) from [<8010e4f8>] (do_handle_IPI+0x30c/0x340)

[   21.373633]  r10:80cfc9fc r9:8155c000 r8:814de000 r7:00000001 r6:1ab7a000 r5:00000001

[   21.387508]  r4:81049380 r3:0a28a839

[   21.394077] [<8010e1ec>] (do_handle_IPI) from [<8010e554>] (ipi_handler+0x28/0x30)

[   21.407596]  r9:8155c000 r8:814de000 r7:00000001 r6:1ab7a000 r5:00000015 r4:814e1380

[   21.421377] [<8010e52c>] (ipi_handler) from [<8018bd10>] (handle_percpu_devid_fasteoi_ipi+0x80/0x154)

[   21.436820] [<8018bc90>] (handle_percpu_devid_fasteoi_ipi) from [<80184d2c>] (generic_handle_irq+0x44/0x54)

[   21.452919]  r7:00000001 r6:814dcb18 r5:80fe60e4 r4:9c8000d0

[   21.461829] [<80184ce8>] (generic_handle_irq) from [<80677d58>] (bcm2836_arm_irqchip_handle_ipi+0xa8/0xc8)

[   21.478048] [<80677cb0>] (bcm2836_arm_irqchip_handle_ipi) from [<80184d2c>] (generic_handle_irq+0x44/0x54)

[   21.494408]  r7:00000001 r6:00000000 r5:00000000 r4:80e91d90

[   21.503468] [<80184ce8>] (generic_handle_irq) from [<8018548c>] (__handle_domain_irq+0x6c/0xc4)

[   21.518933] [<80185420>] (__handle_domain_irq) from [<801012c8>] (bcm2836_arm_irqchip_handle_irq+0x60/0x64)

[   21.535564]  r9:8155c000 r8:00000001 r7:8155df64 r6:ffffffff r5:60000013 r4:80108874

[   21.550210] [<80101268>] (bcm2836_arm_irqchip_handle_irq) from [<80100abc>] (__irq_svc+0x5c/0x7c)

[   21.566150] Exception stack(0x8155df30 to 0x8155df78)

[   21.574713] df20:                                     00000000 00004700 9ba0d344 80119040

[   21.589726] df40: ffffe000 80f05058 80f050a0 00000002 00000001 8103183f 80cfc9fc 8155df8c

[   21.604648] df60: 8155df90 8155df80 80108870 80108874 60000013 ffffffff

[   21.614723] [<8010882c>] (arch_cpu_idle) from [<80a01bc8>] (default_idle_call+0x4c/0x118)

[   21.629664] [<80a01b7c>] (default_idle_call) from [<8015647c>] (do_idle+0x118/0x168)

[   21.644176] [<80156364>] (do_idle) from [<801567a0>] (cpu_startup_entry+0x28/0x30)

[   21.658541]  r10:00000000 r9:410fd034 r8:0000406a r7:8155dff8 r6:10c0387d r5:00000001

[   21.673237]  r4:00000092 r3:60000093

[   21.680150] [<80156778>] (cpu_startup_entry) from [<8010eb68>] (secondary_start_kernel+0x168/0x174)

[   21.695892] [<8010ea00>] (secondary_start_kernel) from [<001018b0>] (0x1018b0)

[   21.706573]  r5:00000055 r4:0155406a

[   21.713438] CPU3: stopping

[   21.719303] CPU: 3 PID: 0 Comm: swapper/3 Not tainted 5.10.76-v7+ #1475

[   21.729227] Hardware name: BCM2835

[   21.735794] Backtrace:

[   21.741347] [<809f2b70>] (dump_backtrace) from [<809f2f00>] (show_stack+0x20/0x24)

[   21.755194]  r7:ffffffff r6:00000000 r5:60000193 r4:80fe5e70

[   21.764055] [<809f2ee0>] (show_stack) from [<809f7114>] (dump_stack+0xcc/0xf8)

[   21.774540] [<809f7048>] (dump_stack) from [<8010e4f8>] (do_handle_IPI+0x30c/0x340)

[   21.788285]  r10:80cfc9fc r9:81560000 r8:814de000 r7:00000001 r6:1aba2000 r5:00000003

[   21.802195]  r4:81049380 r3:0a28a839

[   21.808717] [<8010e1ec>] (do_handle_IPI) from [<8010e554>] (ipi_handler+0x28/0x30)

[   21.822155]  r9:81560000 r8:814de000 r7:00000001 r6:1aba2000 r5:00000015 r4:814e1380

[   21.835963] [<8010e52c>] (ipi_handler) from [<8018bd10>] (handle_percpu_devid_fasteoi_ipi+0x80/0x154)

[   21.851325] [<8018bc90>] (handle_percpu_devid_fasteoi_ipi) from [<80184d2c>] (generic_handle_irq+0x44/0x54)

[   21.867377]  r7:00000001 r6:814dcb18 r5:80fe60e4 r4:9c8000f0

[   21.876289] [<80184ce8>] (generic_handle_irq) from [<80677d58>] (bcm2836_arm_irqchip_handle_ipi+0xa8/0xc8)

[   21.892516] [<80677cb0>] (bcm2836_arm_irqchip_handle_ipi) from [<80184d2c>] (generic_handle_irq+0x44/0x54)

[   21.908884]  r7:00000001 r6:00000000 r5:00000000 r4:80e91d90

[   21.917946] [<80184ce8>] (generic_handle_irq) from [<8018548c>] (__handle_domain_irq+0x6c/0xc4)

[   21.933415] [<80185420>] (__handle_domain_irq) from [<801012c8>] (bcm2836_arm_irqchip_handle_irq+0x60/0x64)

[   21.950046]  r9:81560000 r8:00000001 r7:81561f64 r6:ffffffff r5:60000013 r4:80108874

[   21.964697] [<80101268>] (bcm2836_arm_irqchip_handle_irq) from [<80100abc>] (__irq_svc+0x5c/0x7c)

[   21.980640] Exception stack(0x81561f30 to 0x81561f78)

[   21.989207] 1f20:                                     00000000 00004448 9ba35344 80119040

[   22.004222] 1f40: ffffe000 80f05058 80f050a0 00000008 00000001 8103183f 80cfc9fc 81561f8c

[   22.019148] 1f60: 81561f90 81561f80 80108870 80108874 60000013 ffffffff

[   22.025032] SMP: failed to stop secondary CPUs

[   22.037022] ---[ end Kernel panic - not syncing: At2te0m37ted2 ] --o-[ endkille rniel npaniic t!nexted to kill init! exitcode=0x000002

I don't know enough to diagnose what's causing the failure at the moment, but i'll do some googling and see if i can get any further.

In regards to David saying he has the same issue as my first Zero 2, I'd be interested to find out if there is a correlation between why some Pis work

Here are my 2 Pis. 

The one circled in green gets past the boot loop, the one in red does not. The only difference i can see is the number printed on the back. Not sure if it's relevant, but would be good to see if anything corelates.