On Sun, Jul 30, 2017 at 17:08:18 +0300, Lluís Vilanova wrote: > The hypertrace channel allows guest code to emit events in QEMU (the host) > using > its tracing infrastructure (see "docs/trace.txt"). This works in both 'system' > and 'user' modes, is architecture-agnostic and introduces minimal noise on the > guest. > > See first commit for a full description, use-cases and an example. > > Signed-off-by: Lluís Vilanova <vilan...@ac.upc.edu>
This would be indeed very useful once TCG instrumentation is in place. However, I'm not very excited about this being PCI-only and Linux-only for system mode I wonder how we could make this work on all hosts -- did you consider using "magic" instructions? We'd need a different magic instruction for each guest ISA, but the library would hide that anyway (and the library code would be the same for user and system modes). Thanks, Emilio