Re: [Qemu-devel] [PATCH v2 1/2] fdc: floppy drive should be visible after start without media

[Kevin Wolf <kwolf@redhat.com>]

Am 23.05.2012 11:14, schrieb Markus Armbruster:
> Kevin Wolf <kwolf@redhat.com> writes:
> 
>> Am 22.05.2012 17:00, schrieb Pavel Hrdina:
>>> If you start guest with floppy drive but without media inserted, guest
>>> still should see floppy drive pressent.
>>>
>>> Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
>>> ---
>>>  hw/pc.c |    2 +-
>>>  1 files changed, 1 insertions(+), 1 deletions(-)
>>>
>>> diff --git a/hw/pc.c b/hw/pc.c
>>> index 4d34a33..967c17a 100644
>>> --- a/hw/pc.c
>>> +++ b/hw/pc.c
>>> @@ -382,7 +382,7 @@ void pc_cmos_init(ram_addr_t ram_size, ram_addr_t above_4g_mem_size,
>>>      if (floppy) {
>>>          fdc_get_bs(fd, floppy);
>>>          for (i = 0; i < 2; i++) {
>>> -            if (fd[i] && bdrv_is_inserted(fd[i])) {
>>> +            if (fd[i]) {
>>>                  bdrv_get_floppy_geometry_hint(fd[i], &nb_heads, &max_track,
>>>                                                &last_sect, FDRIVE_DRV_NONE,
>>>                                                &fd_type[i], &rate);
>>
>> I'm not completely sure, but we might have to make this change dependent
>> on the machine type to avoid surprises with live migration.
> 
> What kind of surprises do you have in mind?

A second drive appearing (or appearing in part) after a migration. But
looking closer at the code, this really only changes the CMOS (which is
migrated) and doesn't seem to have any side effects.

Kevin