[v2] hw/block/fdc: floppy command FIFO memory initialization

The uninitialized memory allocated for the command FIFO of the
floppy controller during the VM hardware initialization incurs
many unwanted reports by Valgrind when VM state is being saved.
That verbosity hardens a search for the real memory issues when
the iotests run. Particularly, the patch eliminates 20 unnecessary
reports of the Valgrind tool in the iotest #169.

Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
---
v2:
  01: The pointer unnecessary check 'if (fdctrl->fifo)' was removed
      as suggested by John.

 hw/block/fdc.c | 1 +
 1 file changed, 1 insertion(+)

On 5/29/19 2:20 PM, Andrey Shinkevich wrote:
> The uninitialized memory allocated for the command FIFO of the
> floppy controller during the VM hardware initialization incurs
> many unwanted reports by Valgrind when VM state is being saved.
> That verbosity hardens a search for the real memory issues when
> the iotests run. Particularly, the patch eliminates 20 unnecessary
> reports of the Valgrind tool in the iotest #169.
> 
> Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
> ---
> v2:
>   01: The pointer unnecessary check 'if (fdctrl->fifo)' was removed
>       as suggested by John.
> 
>  hw/block/fdc.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/hw/block/fdc.c b/hw/block/fdc.c
> index 6f19f12..9af762b 100644
> --- a/hw/block/fdc.c
> +++ b/hw/block/fdc.c
> @@ -2647,6 +2647,7 @@ static void fdctrl_realize_common(DeviceState *dev, FDCtrl *fdctrl,
>  
>      FLOPPY_DPRINTF("init controller\n");
>      fdctrl->fifo = qemu_memalign(512, FD_SECTOR_LEN);
> +    memset(fdctrl->fifo, 0, FD_SECTOR_LEN);
>      fdctrl->fifo_size = 512;
>      fdctrl->result_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
>                                               fdctrl_result_timer, fdctrl);
> 

Great, thanks!

Reviewed-by: John Snow <jsnow@redhat.com>

On 5/29/19 2:20 PM, Andrey Shinkevich wrote:
> The uninitialized memory allocated for the command FIFO of the
> floppy controller during the VM hardware initialization incurs
> many unwanted reports by Valgrind when VM state is being saved.
> That verbosity hardens a search for the real memory issues when
> the iotests run. Particularly, the patch eliminates 20 unnecessary
> reports of the Valgrind tool in the iotest #169.
> 
> Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
> ---
> v2:
>   01: The pointer unnecessary check 'if (fdctrl->fifo)' was removed
>       as suggested by John.
> 
>  hw/block/fdc.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/hw/block/fdc.c b/hw/block/fdc.c
> index 6f19f12..9af762b 100644
> --- a/hw/block/fdc.c
> +++ b/hw/block/fdc.c
> @@ -2647,6 +2647,7 @@ static void fdctrl_realize_common(DeviceState *dev, FDCtrl *fdctrl,
>  
>      FLOPPY_DPRINTF("init controller\n");
>      fdctrl->fifo = qemu_memalign(512, FD_SECTOR_LEN);
> +    memset(fdctrl->fifo, 0, FD_SECTOR_LEN);
>      fdctrl->fifo_size = 512;
>      fdctrl->result_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
>                                               fdctrl_result_timer, fdctrl);
> 

I guess technically I would send a PR for this but it's just a single
patch, so it'd be nice if it can just get staged in the next block
roundup by whomever.

Max/Kevin, if you would be so kind?

--js

On 29.05.19 20:20, Andrey Shinkevich wrote:
> The uninitialized memory allocated for the command FIFO of the
> floppy controller during the VM hardware initialization incurs
> many unwanted reports by Valgrind when VM state is being saved.
> That verbosity hardens a search for the real memory issues when
> the iotests run. Particularly, the patch eliminates 20 unnecessary
> reports of the Valgrind tool in the iotest #169.
> 
> Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
> ---
> v2:
>   01: The pointer unnecessary check 'if (fdctrl->fifo)' was removed
>       as suggested by John.
> 
>  hw/block/fdc.c | 1 +
>  1 file changed, 1 insertion(+)

Thanks, applied to my block-on-kevin branch:

https://git.xanclic.moe/XanClic/qemu/commits/branch/block-on-kevin

(To become my block branch when my current pull request is done.)

Max

On 30/05/2019 00:38, Max Reitz wrote:
> On 29.05.19 20:20, Andrey Shinkevich wrote:
>> The uninitialized memory allocated for the command FIFO of the
>> floppy controller during the VM hardware initialization incurs
>> many unwanted reports by Valgrind when VM state is being saved.
>> That verbosity hardens a search for the real memory issues when
>> the iotests run. Particularly, the patch eliminates 20 unnecessary
>> reports of the Valgrind tool in the iotest #169.
>>
>> Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
>> ---
>> v2:
>>    01: The pointer unnecessary check 'if (fdctrl->fifo)' was removed
>>        as suggested by John.
>>
>>   hw/block/fdc.c | 1 +
>>   1 file changed, 1 insertion(+)
> 
> Thanks, applied to my block-on-kevin branch:
> 
> https://git.xanclic.moe/XanClic/qemu/commits/branch/block-on-kevin
> 
> (To become my block branch when my current pull request is done.)
> 
> Max
> 

Thank you very much.
Andrey