Re: [Qemu-devel] [PATCH v2 03/10] target-arm: allow modifying vfp fpexc en bit only

[Juha.Riihimaki]

On Oct 25, 2009, at 14:23, ext Laurent Desnogues wrote:

> On Sat, Oct 24, 2009 at 1:19 PM,  <address@hidden> wrote:
>> From: Juha Riihimäki <address@hidden>
>>
>> All other bits except for the EN in the VFP FPEXC register are  
>> defined
>> as subarchitecture specific and real functionality for any of the
>> other bits has not been implemented in QEMU. However, current code
>> allows modifying all bits in the VFP FPEXC register leading to
>> problems when guest code is writing 1's to the subarchitecture
>> specific bits and checking whether the bits stay up to verify the
>> existence of functionality which in fact does not exist in QEMU.
>
> Shouldn't writes to FPEXC from gdb be protected in the same
> way?  Except for that I agree with your patch.

Please correct me if I'm wrong but it seems to me that the code in  
gdbstub.c never writes anything to the VFP registers, at least it  
seems to me the code in cpu_gdb_write_register and  
cpu_gdb_read_register ignore floating point registers.


Regards,
Juha