Intermittent failure to boot over TFTP after watchdog reset

[petemoore]

Describe the bug
Boot over TFTP fails intermittently after a variable number of reboots on RPi 3B.

To reproduce
Repository https://github.com/petemoore/tftpreboot contains a complete minimal assembly example. This is the disassembly:

   80000:	d53800a0 	mrs	x0, mpidr_el1
   80004:	92400400 	and	x0, x0, #0x3
   80008:	b5000300 	cbnz	x0, 0x80068
   8000c:	1000032a 	adr	x10, 0x80070
   80010:	5280010b 	mov	w11, #0x8                   	// #8
   80014:	2a0b0142 	orr	w2, w10, w11
   80018:	d2971003 	mov	x3, #0xb880                	// #47232
   8001c:	f2a7e003 	movk	x3, #0x3f00, lsl #16
   80020:	b9411864 	ldr	w4, [x3, #280]
   80024:	37ffffe4 	tbnz	w4, #31, 0x80020
   80028:	b9002062 	str	w2, [x3, #32]
   8002c:	b9411864 	ldr	w4, [x3, #280]
   80030:	37f7ffe4 	tbnz	w4, #30, 0x8002c
   80034:	b9400064 	ldr	w4, [x3]
   80038:	6b04005f 	cmp	w2, w4
   8003c:	54ffff81 	b.ne	0x8002c  // b.any
   80040:	d2a7e200 	mov	x0, #0x3f100000            	// #1058013184
   80044:	52ab4001 	mov	w1, #0x5a000000            	// #1509949440
   80048:	52800142 	mov	w2, #0xa                   	// #10
   8004c:	2a010042 	orr	w2, w2, w1
   80050:	b9002402 	str	w2, [x0, #36]
   80054:	b9401c03 	ldr	w3, [x0, #28]
   80058:	121a7463 	and	w3, w3, #0xffffffcf
   8005c:	2a010063 	orr	w3, w3, w1
   80060:	321b0063 	orr	w3, w3, #0x20
   80064:	b9001c03 	str	w3, [x0, #28]
   80068:	d503205f 	wfe
   8006c:	17ffffff 	b	0x80068
   80070:	00000018 	.inst	0x00000018 ; undefined
   80074:	00000000 	.inst	0x00000000 ; undefined
   80078:	00030048 	.inst	0x00030048 ; undefined
   8007c:	00000000 	.inst	0x00000000 ; undefined
   80080:	00000000 	.inst	0x00000000 ; undefined
   80084:	00000000 	.inst	0x00000000 ; undefined

Expected behaviour
This minimal kernel should repeatedly reboot the RPi 3B indefinitely when served over TFTP.

Actual behaviour
After a variable number of reboots, the OS does not start up again. Looking at dnsmasq logs show that after the machine restarts the last time, it requests an IP over DHCP but does not request OS files over TFTP.

System

• Which model of Raspberry Pi? e.g. Pi3B+, PiZeroW
  3B
• Which OS and version (cat /etc/rpi-issue)?
  https://github.com/petemoore/tftpreboot/tree/master/dist
• Which firmware version (vcgencmd version)?
  d5b8d8d
• Which kernel version (uname -a)?
  Custom kernel (see above)

Logs

Here is a trace of the logs from first turning on the RPi until it stops rebooting. It shows initial boot, followed by 4 successful reboots, each around 13 seconds apart, but finally after the last reboot, the RPi 3B requests an IP over DHCP, but does not request bootcode.bin (or any other files) over TFTP:

Apr  4 11:37:41 raspberrypi dnsmasq-dhcp[443]: 653460281 verfügbare(s) DHCP-Subnetz: 192.168.1.255/255.255.255.0
Apr  4 11:37:41 raspberrypi dnsmasq-dhcp[443]: 653460281 "Vendor class": PXEClient:Arch:00000:UNDI:002001
Apr  4 11:37:41 raspberrypi dnsmasq-dhcp[443]: 653460281 PXE(eth0) b8:27:eb:ef:56:44 proxy
Apr  4 11:37:41 raspberrypi dnsmasq-dhcp[443]: 653460281 Marken: eth0
Apr  4 11:37:41 raspberrypi dnsmasq-dhcp[443]: 653460281 Antwort per Rundsendung
Apr  4 11:37:41 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  1 option: 53 message-type  2
Apr  4 11:37:41 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  4 option: 54 server-identifier  192.168.1.186
Apr  4 11:37:41 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  9 option: 60 vendor-class  50:58:45:43:6c:69:65:6e:74
Apr  4 11:37:41 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 17 option: 97 client-machine-id  00:44:44:44:44:44:44:44:44:44:44:44:44:44...
Apr  4 11:37:41 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 32 option: 43 vendor-encap  06:01:03:0a:04:00:50:58:45:09:14:00:00:11...
Apr  4 11:37:42 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/bootsig.bin nicht gefunden
Apr  4 11:37:42 raspberrypi dnsmasq-tftp[443]: /tftpboot/bootcode.bin an 192.168.1.64 verschickt
Apr  4 11:37:42 raspberrypi dnsmasq-dhcp[443]: 653460281 verfügbare(s) DHCP-Subnetz: 192.168.1.255/255.255.255.0
Apr  4 11:37:42 raspberrypi dnsmasq-dhcp[443]: 653460281 "Vendor class": PXEClient:Arch:00000:UNDI:002001
Apr  4 11:37:42 raspberrypi dnsmasq-dhcp[443]: 653460281 PXE(eth0) b8:27:eb:ef:56:44 proxy
Apr  4 11:37:42 raspberrypi dnsmasq-dhcp[443]: 653460281 Marken: eth0
Apr  4 11:37:42 raspberrypi dnsmasq-dhcp[443]: 653460281 Antwort per Rundsendung
Apr  4 11:37:42 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  1 option: 53 message-type  2
Apr  4 11:37:42 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  4 option: 54 server-identifier  192.168.1.186
Apr  4 11:37:42 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  9 option: 60 vendor-class  50:58:45:43:6c:69:65:6e:74
Apr  4 11:37:42 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 17 option: 97 client-machine-id  00:44:56:ef:a2:44:56:ef:a2:44:56:ef:a2:44...
Apr  4 11:37:42 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 32 option: 43 vendor-encap  06:01:03:0a:04:00:50:58:45:09:14:00:00:11...
Apr  4 11:37:42 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/a2ef5644/start.elf nicht gefunden
Apr  4 11:37:42 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/autoboot.txt nicht gefunden
Apr  4 11:37:42 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/config.txt nicht gefunden
Apr  4 11:37:42 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.elf nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: /tftpboot/start.elf an 192.168.1.64 verschickt
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: /tftpboot/fixup.dat an 192.168.1.64 verschickt
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.elf nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/config.txt nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/dt-blob.bin nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.elf nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/config.txt nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/bootcfg.txt nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/bcm2710-rpi-3-b.dtb nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/cmdline.txt nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery8.img nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery8-32.img nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery7.img nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.img nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/kernel8-32.img nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Fehler 0 Early terminate von 192.168.1.64 empfangen
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: konnte /tftpboot/kernel8.img nicht an 192.168.1.64 senden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/kernel7.img nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/kernel.img nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/armstub8.bin nicht gefunden
Apr  4 11:37:45 raspberrypi dnsmasq-tftp[443]: /tftpboot/kernel8.img an 192.168.1.64 verschickt
Apr  4 11:37:54 raspberrypi dnsmasq-dhcp[443]: 653460281 verfügbare(s) DHCP-Subnetz: 192.168.1.255/255.255.255.0
Apr  4 11:37:54 raspberrypi dnsmasq-dhcp[443]: 653460281 "Vendor class": PXEClient:Arch:00000:UNDI:002001
Apr  4 11:37:54 raspberrypi dnsmasq-dhcp[443]: 653460281 PXE(eth0) b8:27:eb:ef:56:44 proxy
Apr  4 11:37:54 raspberrypi dnsmasq-dhcp[443]: 653460281 Marken: eth0
Apr  4 11:37:54 raspberrypi dnsmasq-dhcp[443]: 653460281 Antwort per Rundsendung
Apr  4 11:37:54 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  1 option: 53 message-type  2
Apr  4 11:37:54 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  4 option: 54 server-identifier  192.168.1.186
Apr  4 11:37:54 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  9 option: 60 vendor-class  50:58:45:43:6c:69:65:6e:74
Apr  4 11:37:54 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 17 option: 97 client-machine-id  00:44:44:44:44:44:44:44:44:44:44:44:44:44...
Apr  4 11:37:54 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 32 option: 43 vendor-encap  06:01:03:0a:04:00:50:58:45:09:14:00:00:11...
Apr  4 11:37:55 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/bootsig.bin nicht gefunden
Apr  4 11:37:55 raspberrypi dnsmasq-tftp[443]: /tftpboot/bootcode.bin an 192.168.1.64 verschickt
Apr  4 11:37:55 raspberrypi dnsmasq-dhcp[443]: 653460281 verfügbare(s) DHCP-Subnetz: 192.168.1.255/255.255.255.0
Apr  4 11:37:55 raspberrypi dnsmasq-dhcp[443]: 653460281 "Vendor class": PXEClient:Arch:00000:UNDI:002001
Apr  4 11:37:55 raspberrypi dnsmasq-dhcp[443]: 653460281 PXE(eth0) b8:27:eb:ef:56:44 proxy
Apr  4 11:37:55 raspberrypi dnsmasq-dhcp[443]: 653460281 Marken: eth0
Apr  4 11:37:55 raspberrypi dnsmasq-dhcp[443]: 653460281 Antwort per Rundsendung
Apr  4 11:37:55 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  1 option: 53 message-type  2
Apr  4 11:37:55 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  4 option: 54 server-identifier  192.168.1.186
Apr  4 11:37:55 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  9 option: 60 vendor-class  50:58:45:43:6c:69:65:6e:74
Apr  4 11:37:55 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 17 option: 97 client-machine-id  00:44:56:ef:a2:44:56:ef:a2:44:56:ef:a2:44...
Apr  4 11:37:55 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 32 option: 43 vendor-encap  06:01:03:0a:04:00:50:58:45:09:14:00:00:11...
Apr  4 11:37:55 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/a2ef5644/start.elf nicht gefunden
Apr  4 11:37:55 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/autoboot.txt nicht gefunden
Apr  4 11:37:55 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/config.txt nicht gefunden
Apr  4 11:37:55 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.elf nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: /tftpboot/start.elf an 192.168.1.64 verschickt
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: /tftpboot/fixup.dat an 192.168.1.64 verschickt
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.elf nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/config.txt nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/dt-blob.bin nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.elf nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/config.txt nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/bootcfg.txt nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/bcm2710-rpi-3-b.dtb nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/cmdline.txt nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery8.img nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery8-32.img nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery7.img nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.img nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/kernel8-32.img nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Fehler 0 Early terminate von 192.168.1.64 empfangen
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: konnte /tftpboot/kernel8.img nicht an 192.168.1.64 senden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/kernel7.img nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/kernel.img nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/armstub8.bin nicht gefunden
Apr  4 11:37:58 raspberrypi dnsmasq-tftp[443]: /tftpboot/kernel8.img an 192.168.1.64 verschickt
Apr  4 11:38:00 raspberrypi dnsmasq-dhcp[443]: 2541485621 verfügbare(s) DHCP-Subnetz: 192.168.1.255/255.255.255.0
Apr  4 11:38:00 raspberrypi dnsmasq-dhcp[443]: 2541485621 "Vendor class": android-dhcp-9
Apr  4 11:38:00 raspberrypi dnsmasq-dhcp[443]: 2541485621 Klient stellt Name bereit: RedmiNote7-Redmi
Apr  4 11:38:01 raspberrypi dnsmasq-dhcp[443]: 2541485621 verfügbare(s) DHCP-Subnetz: 192.168.1.255/255.255.255.0
Apr  4 11:38:01 raspberrypi dnsmasq-dhcp[443]: 2541485621 "Vendor class": android-dhcp-9
Apr  4 11:38:01 raspberrypi dnsmasq-dhcp[443]: 2541485621 Klient stellt Name bereit: RedmiNote7-Redmi
Apr  4 11:38:07 raspberrypi dnsmasq-dhcp[443]: 653460281 verfügbare(s) DHCP-Subnetz: 192.168.1.255/255.255.255.0
Apr  4 11:38:07 raspberrypi dnsmasq-dhcp[443]: 653460281 "Vendor class": PXEClient:Arch:00000:UNDI:002001
Apr  4 11:38:07 raspberrypi dnsmasq-dhcp[443]: 653460281 PXE(eth0) b8:27:eb:ef:56:44 proxy
Apr  4 11:38:07 raspberrypi dnsmasq-dhcp[443]: 653460281 Marken: eth0
Apr  4 11:38:07 raspberrypi dnsmasq-dhcp[443]: 653460281 Antwort per Rundsendung
Apr  4 11:38:07 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  1 option: 53 message-type  2
Apr  4 11:38:07 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  4 option: 54 server-identifier  192.168.1.186
Apr  4 11:38:07 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  9 option: 60 vendor-class  50:58:45:43:6c:69:65:6e:74
Apr  4 11:38:07 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 17 option: 97 client-machine-id  00:44:44:44:44:44:44:44:44:44:44:44:44:44...
Apr  4 11:38:07 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 32 option: 43 vendor-encap  06:01:03:0a:04:00:50:58:45:09:14:00:00:11...
Apr  4 11:38:08 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/bootsig.bin nicht gefunden
Apr  4 11:38:08 raspberrypi dnsmasq-tftp[443]: /tftpboot/bootcode.bin an 192.168.1.64 verschickt
Apr  4 11:38:08 raspberrypi dnsmasq-dhcp[443]: 653460281 verfügbare(s) DHCP-Subnetz: 192.168.1.255/255.255.255.0
Apr  4 11:38:08 raspberrypi dnsmasq-dhcp[443]: 653460281 "Vendor class": PXEClient:Arch:00000:UNDI:002001
Apr  4 11:38:08 raspberrypi dnsmasq-dhcp[443]: 653460281 PXE(eth0) b8:27:eb:ef:56:44 proxy
Apr  4 11:38:08 raspberrypi dnsmasq-dhcp[443]: 653460281 Marken: eth0
Apr  4 11:38:08 raspberrypi dnsmasq-dhcp[443]: 653460281 Antwort per Rundsendung
Apr  4 11:38:08 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  1 option: 53 message-type  2
Apr  4 11:38:08 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  4 option: 54 server-identifier  192.168.1.186
Apr  4 11:38:08 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  9 option: 60 vendor-class  50:58:45:43:6c:69:65:6e:74
Apr  4 11:38:08 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 17 option: 97 client-machine-id  00:44:56:ef:a2:44:56:ef:a2:44:56:ef:a2:44...
Apr  4 11:38:08 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 32 option: 43 vendor-encap  06:01:03:0a:04:00:50:58:45:09:14:00:00:11...
Apr  4 11:38:08 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/a2ef5644/start.elf nicht gefunden
Apr  4 11:38:08 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/autoboot.txt nicht gefunden
Apr  4 11:38:08 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/config.txt nicht gefunden
Apr  4 11:38:08 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.elf nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: /tftpboot/start.elf an 192.168.1.64 verschickt
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: /tftpboot/fixup.dat an 192.168.1.64 verschickt
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.elf nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/config.txt nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/dt-blob.bin nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.elf nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/config.txt nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/bootcfg.txt nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/bcm2710-rpi-3-b.dtb nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/cmdline.txt nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery8.img nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery8-32.img nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery7.img nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.img nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/kernel8-32.img nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Fehler 0 Early terminate von 192.168.1.64 empfangen
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: konnte /tftpboot/kernel8.img nicht an 192.168.1.64 senden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/kernel7.img nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/kernel.img nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/armstub8.bin nicht gefunden
Apr  4 11:38:11 raspberrypi dnsmasq-tftp[443]: /tftpboot/kernel8.img an 192.168.1.64 verschickt
Apr  4 11:38:20 raspberrypi dnsmasq-dhcp[443]: 653460281 verfügbare(s) DHCP-Subnetz: 192.168.1.255/255.255.255.0
Apr  4 11:38:20 raspberrypi dnsmasq-dhcp[443]: 653460281 "Vendor class": PXEClient:Arch:00000:UNDI:002001
Apr  4 11:38:20 raspberrypi dnsmasq-dhcp[443]: 653460281 PXE(eth0) b8:27:eb:ef:56:44 proxy
Apr  4 11:38:20 raspberrypi dnsmasq-dhcp[443]: 653460281 Marken: eth0
Apr  4 11:38:20 raspberrypi dnsmasq-dhcp[443]: 653460281 Antwort per Rundsendung
Apr  4 11:38:20 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  1 option: 53 message-type  2
Apr  4 11:38:20 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  4 option: 54 server-identifier  192.168.1.186
Apr  4 11:38:20 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  9 option: 60 vendor-class  50:58:45:43:6c:69:65:6e:74
Apr  4 11:38:20 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 17 option: 97 client-machine-id  00:44:44:44:44:44:44:44:44:44:44:44:44:44...
Apr  4 11:38:20 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 32 option: 43 vendor-encap  06:01:03:0a:04:00:50:58:45:09:14:00:00:11...
Apr  4 11:38:22 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/bootsig.bin nicht gefunden
Apr  4 11:38:22 raspberrypi dnsmasq-tftp[443]: /tftpboot/bootcode.bin an 192.168.1.64 verschickt
Apr  4 11:38:22 raspberrypi dnsmasq-dhcp[443]: 653460281 verfügbare(s) DHCP-Subnetz: 192.168.1.255/255.255.255.0
Apr  4 11:38:22 raspberrypi dnsmasq-dhcp[443]: 653460281 "Vendor class": PXEClient:Arch:00000:UNDI:002001
Apr  4 11:38:22 raspberrypi dnsmasq-dhcp[443]: 653460281 PXE(eth0) b8:27:eb:ef:56:44 proxy
Apr  4 11:38:22 raspberrypi dnsmasq-dhcp[443]: 653460281 Marken: eth0
Apr  4 11:38:22 raspberrypi dnsmasq-dhcp[443]: 653460281 Antwort per Rundsendung
Apr  4 11:38:22 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  1 option: 53 message-type  2
Apr  4 11:38:22 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  4 option: 54 server-identifier  192.168.1.186
Apr  4 11:38:22 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  9 option: 60 vendor-class  50:58:45:43:6c:69:65:6e:74
Apr  4 11:38:22 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 17 option: 97 client-machine-id  00:44:56:ef:a2:44:56:ef:a2:44:56:ef:a2:44...
Apr  4 11:38:22 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 32 option: 43 vendor-encap  06:01:03:0a:04:00:50:58:45:09:14:00:00:11...
Apr  4 11:38:22 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/a2ef5644/start.elf nicht gefunden
Apr  4 11:38:22 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/autoboot.txt nicht gefunden
Apr  4 11:38:22 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/config.txt nicht gefunden
Apr  4 11:38:22 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.elf nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: /tftpboot/start.elf an 192.168.1.64 verschickt
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: /tftpboot/fixup.dat an 192.168.1.64 verschickt
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.elf nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/config.txt nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/dt-blob.bin nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.elf nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/config.txt nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/bootcfg.txt nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/bcm2710-rpi-3-b.dtb nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/cmdline.txt nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery8.img nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery8-32.img nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery7.img nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.img nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/kernel8-32.img nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Fehler 0 Early terminate von 192.168.1.64 empfangen
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: konnte /tftpboot/kernel8.img nicht an 192.168.1.64 senden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/kernel7.img nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/kernel.img nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/armstub8.bin nicht gefunden
Apr  4 11:38:25 raspberrypi dnsmasq-tftp[443]: /tftpboot/kernel8.img an 192.168.1.64 verschickt
Apr  4 11:38:34 raspberrypi dnsmasq-dhcp[443]: 653460281 verfügbare(s) DHCP-Subnetz: 192.168.1.255/255.255.255.0
Apr  4 11:38:34 raspberrypi dnsmasq-dhcp[443]: 653460281 "Vendor class": PXEClient:Arch:00000:UNDI:002001
Apr  4 11:38:34 raspberrypi dnsmasq-dhcp[443]: 653460281 PXE(eth0) b8:27:eb:ef:56:44 proxy
Apr  4 11:38:34 raspberrypi dnsmasq-dhcp[443]: 653460281 Marken: eth0
Apr  4 11:38:34 raspberrypi dnsmasq-dhcp[443]: 653460281 Antwort per Rundsendung
Apr  4 11:38:34 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  1 option: 53 message-type  2
Apr  4 11:38:34 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  4 option: 54 server-identifier  192.168.1.186
Apr  4 11:38:34 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  9 option: 60 vendor-class  50:58:45:43:6c:69:65:6e:74
Apr  4 11:38:34 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 17 option: 97 client-machine-id  00:44:44:44:44:44:44:44:44:44:44:44:44:44...
Apr  4 11:38:34 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 32 option: 43 vendor-encap  06:01:03:0a:04:00:50:58:45:09:14:00:00:11...
Apr  4 11:38:35 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/bootsig.bin nicht gefunden
Apr  4 11:38:35 raspberrypi dnsmasq-tftp[443]: /tftpboot/bootcode.bin an 192.168.1.64 verschickt
Apr  4 11:38:35 raspberrypi dnsmasq-dhcp[443]: 653460281 verfügbare(s) DHCP-Subnetz: 192.168.1.255/255.255.255.0
Apr  4 11:38:35 raspberrypi dnsmasq-dhcp[443]: 653460281 "Vendor class": PXEClient:Arch:00000:UNDI:002001
Apr  4 11:38:35 raspberrypi dnsmasq-dhcp[443]: 653460281 PXE(eth0) b8:27:eb:ef:56:44 proxy
Apr  4 11:38:35 raspberrypi dnsmasq-dhcp[443]: 653460281 Marken: eth0
Apr  4 11:38:35 raspberrypi dnsmasq-dhcp[443]: 653460281 Antwort per Rundsendung
Apr  4 11:38:35 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  1 option: 53 message-type  2
Apr  4 11:38:35 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  4 option: 54 server-identifier  192.168.1.186
Apr  4 11:38:35 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  9 option: 60 vendor-class  50:58:45:43:6c:69:65:6e:74
Apr  4 11:38:35 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 17 option: 97 client-machine-id  00:44:56:ef:a2:44:56:ef:a2:44:56:ef:a2:44...
Apr  4 11:38:35 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 32 option: 43 vendor-encap  06:01:03:0a:04:00:50:58:45:09:14:00:00:11...
Apr  4 11:38:35 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/a2ef5644/start.elf nicht gefunden
Apr  4 11:38:35 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/autoboot.txt nicht gefunden
Apr  4 11:38:35 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/config.txt nicht gefunden
Apr  4 11:38:35 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.elf nicht gefunden
Apr  4 11:38:38 raspberrypi dnsmasq-tftp[443]: /tftpboot/start.elf an 192.168.1.64 verschickt
Apr  4 11:38:38 raspberrypi dnsmasq-tftp[443]: /tftpboot/fixup.dat an 192.168.1.64 verschickt
Apr  4 11:38:38 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.elf nicht gefunden
Apr  4 11:38:38 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/config.txt nicht gefunden
Apr  4 11:38:38 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/dt-blob.bin nicht gefunden
Apr  4 11:38:38 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.elf nicht gefunden
Apr  4 11:38:38 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/config.txt nicht gefunden
Apr  4 11:38:39 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/bootcfg.txt nicht gefunden
Apr  4 11:38:39 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/bcm2710-rpi-3-b.dtb nicht gefunden
Apr  4 11:38:39 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/cmdline.txt nicht gefunden
Apr  4 11:38:39 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery8.img nicht gefunden
Apr  4 11:38:39 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery8-32.img nicht gefunden
Apr  4 11:38:39 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery7.img nicht gefunden
Apr  4 11:38:39 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/recovery.img nicht gefunden
Apr  4 11:38:39 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/kernel8-32.img nicht gefunden
Apr  4 11:38:39 raspberrypi dnsmasq-tftp[443]: Fehler 0 Early terminate von 192.168.1.64 empfangen
Apr  4 11:38:39 raspberrypi dnsmasq-tftp[443]: konnte /tftpboot/kernel8.img nicht an 192.168.1.64 senden
Apr  4 11:38:39 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/kernel7.img nicht gefunden
Apr  4 11:38:39 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/kernel.img nicht gefunden
Apr  4 11:38:39 raspberrypi dnsmasq-tftp[443]: Datei /tftpboot/armstub8.bin nicht gefunden
Apr  4 11:38:39 raspberrypi dnsmasq-tftp[443]: /tftpboot/kernel8.img an 192.168.1.64 verschickt
Apr  4 11:38:47 raspberrypi dnsmasq-dhcp[443]: 653460281 verfügbare(s) DHCP-Subnetz: 192.168.1.255/255.255.255.0
Apr  4 11:38:47 raspberrypi dnsmasq-dhcp[443]: 653460281 "Vendor class": PXEClient:Arch:00000:UNDI:002001
Apr  4 11:38:47 raspberrypi dnsmasq-dhcp[443]: 653460281 PXE(eth0) b8:27:eb:ef:56:44 proxy
Apr  4 11:38:47 raspberrypi dnsmasq-dhcp[443]: 653460281 Marken: eth0
Apr  4 11:38:47 raspberrypi dnsmasq-dhcp[443]: 653460281 Antwort per Rundsendung
Apr  4 11:38:47 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  1 option: 53 message-type  2
Apr  4 11:38:47 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  4 option: 54 server-identifier  192.168.1.186
Apr  4 11:38:47 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size:  9 option: 60 vendor-class  50:58:45:43:6c:69:65:6e:74
Apr  4 11:38:47 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 17 option: 97 client-machine-id  00:44:44:44:44:44:44:44:44:44:44:44:44:44...
Apr  4 11:38:47 raspberrypi dnsmasq-dhcp[443]: 653460281 sent size: 32 option: 43 vendor-encap  06:01:03:0a:04:00:50:58:45:09:14:00:00:11...
Apr  4 11:39:14 raspberrypi dnsmasq-dhcp[443]: 3277451874 verfügbare(s) DHCP-Subnetz: 192.168.1.255/255.255.255.0
Apr  4 11:39:14 raspberrypi dnsmasq-dhcp[443]: 3277451874 "Vendor class": android-dhcp-7.0
Apr  4 11:39:14 raspberrypi dnsmasq-dhcp[443]: 3277451874 Klient stellt Name bereit: android-6c045801e129ae47
Apr  4 11:39:15 raspberrypi dnsmasq-dhcp[443]: 3277451874 verfügbare(s) DHCP-Subnetz: 192.168.1.255/255.255.255.0
Apr  4 11:39:15 raspberrypi dnsmasq-dhcp[443]: 3277451874 "Vendor class": android-dhcp-7.0
Apr  4 11:39:15 raspberrypi dnsmasq-dhcp[443]: 3277451874 Klient stellt Name bereit: android-6c045801e129ae47

Additional context
First reported in "Bare metal, Assembly language" forum.