Re: [Qemu-devel] [PATCH v1 2/2] gdbstub: Fix vCont behaviour

[Claudio Imbrenda]

On 12/10/16 15:15, David Hildenbrand wrote:
>>> +            for (cx = 0; ccpus && ccpus[cx]; cx++) {
>>> +                cpu_single_step(cpu, 0);
> 
> This looks suspicious

why? we set all cpus to single step, since that is the default, and then
we clear the single-step property from all CPUs that should be restarted
in normal mode, then we restart all CPUs. Those in single-step will
indeed only perform one single step, the others will run freely (at
least until the first single-step CPU stops again).

>>> +            }
>>> +            CPU_FOREACH(cpu) {
>>> +                cpu_resume(cpu);
>>> +            }
> 
> Claudio, did you have a look at how s->c_cpu is used later on? I remember 
> that we
> have to take care of some query reply packages.

yes, that's set by the H packet and used by the c,s,m,etc packets. vCont
ignores it and doesn't change it
(see here https://sourceware.org/gdb/onlinedocs/gdb/Packets.html )