QEMU doesn't implement ARMv4/v5 legacy SCTLR.U==0 load-and-rotate unaligned access handling Description of problem: **ldr r7, \[r0, r1\]** works differently on real device and QEMU. Probably all **ldr Rd, \[Rs\]** commands works wrongly in QEMU with Raspberry Pi emulation. Steps to reproduce: 1. Launch the attached software **kernel_qemu.img** in QEMU. 2. Launch the attached software **kerenel.img** on real Raspberry Pi 1B+. 3. Look at the r7. It contains different data. Additional information: **kernel_qemu.img** and **kerenel.img** are the same program. It just compiled with different origins - 0x8000 for real device and 0x10000 for QEMU. But code inside the program works at the same addresses. r0 = 0x183a4 r1 = 0x817 **\[r0, r1\]** points to byte 0x42 in memory with such data: **0x80 0x15 0x22 \[0x42\] 0x03 0x21 0x87** After **ldr r7, \[r0, r1\]** execution real device puts to r7: **0x22158042** After **ldr r7, \[r0, r1\]** execution QEMU puts to r7: **0x87210342** QEMU: ![QEMU.png](/uploads/51ecbf1689d36f969cb482f2613ccb58/QEMU.png) Real Raspberry Pi 1B+: ![real.jpg](/uploads/2a9cc3f4bc33d7f254c549e5086070a7/real.jpg) [kernel_qemu.img](/uploads/ae6a7490660569d5fe56adc9f4dde85d/kernel_qemu.img) [kernel.img](/uploads/48c94a66370c1fe8720fe89603c45c7b/kernel.img)