I hit the same problem and did some initial investigation with Toshifumi. Here is a more exhaustive test program I wrote based on the post on the Apple Developer Forums and the result shows that very interesting behavior of mmap and mprotect since macOS 11.2.
https://gist.github.com/hikalium/75ae822466ee4da13cbbe486498a191f I and my friend confirmed that all mmap & following mprotect calls with any protection bit combinations are succeeded up to 11.1 on M1 Mac but starting from 11.2 mprotect starts failing if we call mmap with PROT_WRITE + PROT_EXEC. (Surprisingly, mmap itself is not failing even on those patterns.) It looks like the allocation of code gen buffer in QEMU uses this combination at mmap call: https://github.com/qemu/qemu/blob/master/accel/tcg/translate-all.c#L1294 So maybe we need to specify PROT_NONE instead on the initial mmap and change it appropriately afterwards to make it working on M1 Mac after 11.2. (We tried to fix it but we have no sufficient knowledge about tcg... Could you take a look into it?) -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1914849 Title: mprotect fails after MacOS 11.2 on arm mac Status in QEMU: New Bug description: I got the following error when I ran qemu on arm mac(MacOS 11.2). ``` $ ./qemu-system-x86_64 qemu-system-x86_64: qemu_mprotect__osdep: mprotect failed: Permission denied ** ERROR:../tcg/tcg.c:844:tcg_region_init: assertion failed: (!rc) Bail out! ERROR:../tcg/tcg.c:844:tcg_region_init: assertion failed: (!rc) [1] 34898 abort ./qemu-system-x86_64 ``` I tested the same version of qemu on intel mac(MacOS 11.2), but it works fine. And my friend told me that they did not have this error with MacOS 11.1. So, I think it is CPU architecture or an OS version dependent error. Environment: Qemu commit id: d0dddab40e472ba62b5f43f11cc7dba085dabe71 OS: MacOS 11.2(20D64) Hardware: MacBook Air (M1, 2020) How to build: ``` mkdir build/ cd build/ ../configure --target-list=aarch64-softmmu,x86_64-softmmu make ``` How to reproduce: ``` ./qemu-system-x86_64 ``` Error message: ``` $ ./qemu-system-x86_64 qemu-system-x86_64: qemu_mprotect__osdep: mprotect failed: Permission denied ** ERROR:../tcg/tcg.c:844:tcg_region_init: assertion failed: (!rc) Bail out! ERROR:../tcg/tcg.c:844:tcg_region_init: assertion failed: (!rc) [1] 34898 abort ./qemu-system-x86_64 ``` To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1914849/+subscriptions
