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Diffstat (limited to 'results/classifier/accel-gemma3:12b/kvm/2916')
| -rw-r--r-- | results/classifier/accel-gemma3:12b/kvm/2916 | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/results/classifier/accel-gemma3:12b/kvm/2916 b/results/classifier/accel-gemma3:12b/kvm/2916 new file mode 100644 index 000000000..32ee3ffa4 --- /dev/null +++ b/results/classifier/accel-gemma3:12b/kvm/2916 @@ -0,0 +1,27 @@ + +qemu-system-arm hangs when attempting to enable MMU on Cortex-A7 +Description of problem: +QEMU 9.x.x+ hangs when attempting to do enable the MMU from SCTLRL - M bit: https://developer.arm.com/documentation/ddi0601/2025-03/AArch32-Registers/SCTLR--System-Control-Register + +The instruction that hangs is the writing of the SCTLR register: + +``` +mrc p15, 0, r0, c1, c0, 0 +orr r0, r0, 1 +mcr p15, 0, r0, c1, c0, 0 +``` + +I am attempting to enable unaligned accesses and SCTLR-A bit doesn't seem to have any effect if the SCTLR-M is not enabled. Doing an unaligned access on cortex-a7 should be supported but it always trigger a Fault. +Steps to reproduce: +1. add the mrc/orr/mcr instruction sequence in the ResetHandler +2. link the elf +3. attempt to execute it +Additional information: +The unaligned access looked like it was working in QEMU 8.x.x but it might not have been emulated(?). I also am facing the same issues with MCR hanging and unaligned access not supported with latest 10.0.0-RC2. + +When it hangs, QEMU has to be killed and terminal reset. + +There might be two separate issues here: + +1. writing SCTLR register +2. emulated cortex-a7 not supporting unaligned access (hardware supports it) |