# Can't boot 23.09 SDK with current QEMU x86\_64; older versions are fine **URL:** \ **Category:** VxWorks SDK\ **Created:** [October 20, 2023, 4:18am UTC](https://forums.windriver.com/t/cant-boot-23-09-sdk-with-current-qemu-x86-64-older-versions-are-fine/250 "2023-10-20T04:18:48Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![trnsz](https://yyz1.discourse-cdn.com/flex035/user_avatar/forums.windriver.com/trnsz/32/63_2.png) [@trnsz](https://forums.windriver.com/u/trnsz)\ **Post date:** [October 20, 2023, 4:18am UTC](https://forums.windriver.com/t/cant-boot-23-09-sdk-with-current-qemu-x86-64-older-versions-are-fine/250/1 "2023-10-20T04:18:49Z")
@dan.milea The x86\_64 v1.13 23.09 SDK doesn’t work for me out of the box on a Fedora 39 system using QEMU v8.1.1. Attempting to boot the VxWorks kernel with QEMU just results in QEMU using 100% CPU time and hanging until forcibly terminated (via ^C), with no output ever shown. The previous x86\_64 v1.12.1 23.03 SDK works just fine, as do all previous SDK versions going way back through the archives. While I didn’t try QEMU v8.1.2 (the current version), I did build the older QEMU v7.2.6 from sources, and this worked – so you need an old QEMU version with the new SDKs, but the new QEMU works with old SDKs. Since that’s rather non-intuitive, I assume it’s a bug and not intended behavior. ---
**Author:** ![dan.milea](https://avatars.discourse-cdn.com/v4/letter/d/4bbf92/32.png) [@dan.milea](https://forums.windriver.com/u/dan.milea)\ **Post date:** [October 24, 2023, 6:56am UTC](https://forums.windriver.com/t/cant-boot-23-09-sdk-with-current-qemu-x86-64-older-versions-are-fine/250/2 "2023-10-24T06:56:18Z")
@trnsz Thanks for reporting the issue. Version [1.13.1](https://d13321s3lxgewa.cloudfront.net/wrsdk-vxworks7-qemu-1.13.1.tar.bz2) of the QEMU SDK contains a fix for the problem. The VxWorks kernel it includes works with QEMU 8.1.1.