[Qemu-devel] regarding bug name : -hda FAT:. limited to 504MBytes

[Qemu-devel] regarding bug name : -hda FAT:. limited to 504MBytes

[Shubham Kumar]

Since the problem seems like the used FAT-16 file system , 
Will it solve the problem if I change the code of  vvfat.c for FAT-32 file system to increase acceptable file size ?

Regards
Shubham Kumar

Re: [Qemu-devel] regarding bug name : -hda FAT:. limited to 504MBytes

[Thomas Huth]

 Hi,

On 14.02.2017 22:38, Shubham Kumar wrote:
> Since the problem seems like the used FAT-16 file system , 
> Will it solve the problem if I change the code of  vvfat.c for FAT-32 file system to increase acceptable file size ?

As far as I know, FAT16 can already support up to 4GB file systems, so
that limitation to 504 MB must be something different.
It's maybe best if you put the qemu-block mailing list on CC:, to get
the attention of the block/disk expert, too. Maybe there's someone
around who knows the vvfat code and its limitations and can give a good
answer here...

 Thomas

Re: [Qemu-devel] [Qemu-block] regarding bug name : -hda FAT:. limited to 504MBytes

[Kevin Wolf]

Am 14.02.2017 um 23:24 hat Thomas Huth geschrieben:
> On 14.02.2017 22:38, Shubham Kumar wrote:
> > Since the problem seems like the used FAT-16 file system , 
> > Will it solve the problem if I change the code of  vvfat.c for FAT-32 file system to increase acceptable file size ?
> 
> As far as I know, FAT16 can already support up to 4GB file systems, so
> that limitation to 504 MB must be something different.
> It's maybe best if you put the qemu-block mailing list on CC:, to get
> the attention of the block/disk expert, too. Maybe there's someone
> around who knows the vvfat code and its limitations and can give a good
> answer here...

None of the active developers know, or want to know, the vvfat code.

There is some FAT32 support there, but if you use it:

    fprintf(stderr, "Big fat greek warning: FAT32 has not been tested. "
                    "You are welcome to do so!\n");

So if you just want to play with it, go ahead. But if you care about
your data, maybe vvfat isn't the right tool anyway.

Kevin