On Sat, 27 Jul 2019 00:10:32 +0200 Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote: > Does the userspace API > cover only syscall or perhaps sysfs interfaces? There are more API > files (amd-memory-encryption.txt, cpuid.txt, halt-polling.txt msr.txt, > ppc-pv.txt, s390-diag.txt) but, with the exception of > amd-memory-encryption.txt and halt-polling.txt, they cover the > emulated-hardware interfaces that KVM provides to virtual machines. The user-space API certainly goes beyond system calls. For sysfs, I guess, the question would be whether a given knob is something that an application would use (userspace-api) or something that a sysadmin would want to tweak (admin-guide). Thanks, jon