Re: [PATCH RFC V3 1/5] xen: Emulate with no writes

[Razvan Cojocaru <rcojocaru@bitdefender.com>]

On 07/24/2014 02:20 PM, Tim Deegan wrote:
> Hi,
> 
> At 15:34 +0300 on 23 Jul (1406126080), Razvan Cojocaru wrote:
>> +static const struct x86_emulate_ops hvm_emulate_ops_no_write = {
>> +    .read          = hvmemul_read,
>> +    .insn_fetch    = hvmemul_insn_fetch,
>> +    .write         = hvmemul_write_discard,
>> +    .cmpxchg       = hvmemul_cmpxchg,
>> +    .rep_ins       = hvmemul_rep_ins,
>> +    .rep_outs      = hvmemul_rep_outs,
>> +    .rep_movs      = hvmemul_rep_movs,
> 
> If you want to discard all writes from this guest instruction, you'll
> also need modified versions of the rep_ins, rep_movs and cmpxchg
> handlers.

Noted, thanks.

>> +    .read_segment  = hvmemul_read_segment,
>> +    .write_segment = hvmemul_write_segment,
>> +    .read_io       = hvmemul_read_io,
>> +    .write_io      = hvmemul_write_io,
>> +    .read_cr       = hvmemul_read_cr,
>> +    .write_cr      = hvmemul_write_cr,
>> +    .read_msr      = hvmemul_read_msr,
>> +    .write_msr     = hvmemul_write_msr,
>> +    .wbinvd        = hvmemul_wbinvd,
>> +    .cpuid         = hvmemul_cpuid,
>> +    .inject_hw_exception = hvmemul_inject_hw_exception,
>> +    .inject_sw_interrupt = hvmemul_inject_sw_interrupt,
> 
> Do you care about injecting exceptions (stack updates &c)?

Yes, those should work.


Thanks,
Razvan Cojocaru