Re: [Qemu-devel] [PATCH 1/7] block: Remove dead code

[Kevin Wolf <kwolf@redhat.com>]

Am 27.10.2011 09:37, schrieb Stefan Hajnoczi:
> On Wed, Oct 26, 2011 at 02:31:16PM +0200, Kevin Wolf wrote:
>> @@ -2039,11 +2039,7 @@ const char *bdrv_get_encrypted_filename(BlockDriverState *bs)
>>  void bdrv_get_backing_filename(BlockDriverState *bs,
>>                                 char *filename, int filename_size)
>>  {
>> -    if (!bs->backing_file) {
>> -        pstrcpy(filename, filename_size, "");
>> -    } else {
>> -        pstrcpy(filename, filename_size, bs->backing_file);
>> -    }
>> +    pstrcpy(filename, filename_size, bs->backing_file);
>>  }
> 
> I think this points to another problem:
> 
> bs->backing_file[] is never cleared across bdrv_close()/bdrv_open().
> 
> If we open an image file that uses a backing file, then close the
> BlockDriverState, and then open a file which does not use a backing file
> we're left with the old backing file!

Ouch! Care to send a fix?

Did you check if there are more fields in BlockDriverState that should
be cleared?

Kevin