graphic: 0.898 peripherals: 0.894 boot: 0.829 kernel: 0.814 device: 0.812 ppc: 0.761 socket: 0.712 architecture: 0.711 semantic: 0.614 performance: 0.600 permissions: 0.578 register: 0.569 PID: 0.566 risc-v: 0.553 mistranslation: 0.514 vnc: 0.495 network: 0.494 files: 0.490 user-level: 0.470 arm: 0.407 VMM: 0.407 debug: 0.405 i386: 0.368 x86: 0.356 KVM: 0.341 TCG: 0.341 hypervisor: 0.326 virtual: 0.314 assembly: 0.215 qemu-system-mipsel regression, Linux generated with Buildroot does not boot anymore Description of problem: Buildroot Toolchain Builders try to release a new version. See a message from Thomas Petazzoni with the remaining issues: https://lore.kernel.org/buildroot/20240730223542.273693e5@windsurf/T/#u All toolchains generate a system that fails to boot: Run /sbin/init as init process process '/bin/busybox' started with executable stack Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000004 The interesting thing is that those images boot fine with Qemu v8.2.6, but they fail to boot with Qemu v9.0.2. I tracked it down to this commit: commit 4e999bf4197ae3dc58b7092260f98146920a7469 Author: Richard Henderson Date: Sun Jan 28 15:58:52 2024 +1000 target/mips: Pass ptw_mmu_idx down from mips_cpu_tlb_fill Rather than adjust env->hflags so that the value computed by cpu_mmu_index() changes, compute the mmu_idx that we want directly and pass it down. Introduce symbolic constants for MMU_{KERNEL,ERL}_IDX. Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Richard Henderson Unfortunately just reverting this commit in 9.0.2 does not help, Qemu segfaults on Linux Kernel boot then.