If you've flashed a Linux kernel to an embedded board with U-Boot, you've probably seen this: I want to make an unfashionable argument: this error message isn't a bug report about your SD card. It's a bug report about the image format... Read more

A board that resets itself during boot, over and over, in a tight loop — no crash dump, no kernel panic, just silence and then the power LED blinking again — is one of the more demoralizing bugs in embedded Linux. Community threads about STM32MP1 boards hitting exactly this pattern eventually converge on the same diagnosis: the watchdog timeout was shorter than the boot actually took. Engineers had to shrink the timeout on purpose just to reproduce it reliably, because in normal conditions the margin was just wide enough to hide the bug... Read more