Re: [Qemu-devel] [PATCH 2/8] qcow2: add dirty-bitmaps feature

[Vladimir Sementsov-Ogievskiy]

On 10.06.2015 17:30, Stefan Hajnoczi wrote:
> On Mon, Jun 08, 2015 at 06:21:20PM +0300, Vladimir Sementsov-Ogievskiy wrote:
>
>
>
> > +    ret = bdrv_pread(bs->file, bm->l1_table_offset, l1_table,
> > +                     bm->l1_size * sizeof(uint64_t));
> > +    if (ret < 0) {
> > +        goto fail;
> > +    }
> > +
> > +    buf = g_malloc0(bm->l1_size * s->cluster_size);
> What is the maximum l1_size value?  cluster_size and l1_size are 32-bit
> so with 64 KB cluster_size this overflows if l1_size > 65535.  Do you
> want to cast to size_t?

Hmm. What the maximum RAM space we'd like to spend on dirty bitmap? I 
think 4Gb is too much.. So here should be limited not the l1_size but 
number of bytes needed to store the bitmap. What is maximum disk size we 
are dealing with?


--
Best regards,
Vladimir
* now, @virtuozzo.com instead of @parallels.com. Sorry for this inconvenience.