FLOSS virtualization hacker, occasional brewer

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Joined 2 years ago
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Cake day: June 9th, 2023

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  • There is a very large corpus of FLOSS software out there serving everything from individual itches to whole industries. Any project that is important to someone’s bottom line is likely to have paid developers working on it but often alongside hobbyists.

    The project I predominately work on is about 90% paid developers but from lots of different companies and organisations. Practically though the developers don’t care about the affiliation of the other developers they work with but the ideas and patches they bring to the project.








  • QEMU is always going to focus on emulation fidelity first and there are few shortcuts. With floating point the differences aren’t generally in the numbers but in how the NaNs and other edge cases are handled. If you want to execute FP heavy code you should be cross compiling anyway.





  • Pretty much. From v8.0 onwards all the extra features are indicated by id flags. Stuff that is relevant to kernel mode will generally be automatically handled by the kernel patching itself on booting up and in user space some libraries will select appropriately accelerated functions when the ISA extensions are probed. There are a bunch off advisory instructions encoded in the hint space that will be effectively NOPs on older hardware but will enhance execution if run on newer hardware.

    If you want to play with newer instructions have a look at QEMUs “max” CPU.