In the absence of further information from the submitter, it seems reasonable to assume that this is indeed the bug fixed by commit db812c4073c77 (which resulted in this assertion when running OpenBSD guests). That commit is in 3.1, which was released in December.
** Changed in: qemu Status: New => Fix Released -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1795148 Title: address_space_stw_le_cached: Assertion `addr < cache->len && 2 <= cache ->len - addr' failed Status in QEMU: Fix Released Bug description: When running OpenBSD-current as a guest, the following assertion is hit after a few seconds, resulting in the virtual machine to crash: ``` qemu-system-x86_64: /build/qemu/src/qemu-3.0.0/include/exec/memory_ldst_cached.inc.h:85: address_space_stw_le_cached: Assertion `addr < cache->len && 2 <= cache->len - addr' failed. ``` Host is Arch Linux stable, running on x86_64. Qemu version is 3.0.0, installed via the standard Arch Linux package. Version 2.12.1 didn't exhibit this behavior. To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1795148/+subscriptions