Alexander Graf wrote: > On 13.04.2010, at 15:36, Jan Kiszka wrote: > >> Jun Koi wrote: >>> Hi, >>> >>> I am looking into the singlestep command in monitor interface, and it >>> seems that we only take into account the singlestep flag when we are >>> translating code. >>> So for the already-translated code, we will miss singlestep? >> This feature is broken. For TCG, it should at least flush the >> translation buffer, and for KVM it has to enable single-stepping in the >> kernel. That's what happens automatically when you call cpu_single_step. >> I guess 'singlestep' wants to be somehow orthogonal to this. But this is >> the wrong approach. >> >> Does anyone actually used this feature or still does so? It looks fairly >> redundant to me, kind of a poor-man's gdb front-end as part of the >> monitor console. > > Not sure what it does, but I use -singlestep quite a lot to get register > dumps for instructions when using -d cpu.
Ah, "singlestep" is not about stopping the VM after each instruction but about limiting the TB length to a single instruction. Badly named and poorly documented. In that case, the dynamic switch should already be fine by adding a tb_flush() on enable. Still, someone should also patch at least the docs. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux
