@wlisac just to give you some context … It’s a longer story, I’ll try to make it short. ARMv6 has CP15 barrier instructions. These are deprecated since ARMv7. Linux kernel can emulate or HW exec them (if CPU supports it). Some details here. Our builders have ARMv8 CPU and the kernel was configured to emulate these instructions. Unfortunately, we’ve found that the emulation doesn’t work. I experienced same issue (hang) with Rust installer and other ARMv6 binaries running on our builders. Started digging, found the kernel issue and the fix was deployed this Tuesday (23rd April). Here’re other details if you’re interested. In other words, any ARMv6 binary using CP15 barrier instructions was affected. That’s the reason why it started to work for you.