On 16/12/19 10:14, Vitaly Kuznetsov wrote: >> Well, I would like to receive Vitaly's comments here. Vitaly, it seems it's >> more realistic to fix the issue from kvm_stat side according to the comments >> given by Marc? >> > Sure, if we decide to treat tracepoints as ABI then fixing users is > likely the way to go. Personally, I think that we should have certain > freedom with them and consider only tools which live in linux.git when > making changes (and changing the tool to match in the same patch series > is OK from this PoV, no need to support all possible versions of the > tool). I'd agree with that, plus trace-cmd since it has a KVM plugin, especially since KVM has for example debugfs stats unlike other subsystems (and we're tracing debugfs stats as stable userspace API, and planning to move them somewhere out of debugfs). But I wouldn't complain either if architecture maintainers feel differently. Paolo > Also, we can be a bit more conservative and in this particular case > instead of renaming fields just add 'exit_reason' to all architectures > where it's missing. For ARM, 'esr_ec' will then stay with what it is and > 'exit_reason' may contain something different (like the information why > the guest exited actually). But I don't know much about ARM specifics > and I'm not sure how feasible the suggestion would be.
