Re: [PATCH 0/2] vvfat: fix two crashes.

[Programmingkid]

> On May 24, 2021, at 12:56 PM, Vladimir Sementsov-Ogievskiy 
> <vsementsov@virtuozzo.com> wrote:
> 
> 24.05.2021 19:06, Programmingkid wrote:
>>> On May 24, 2021, at 11:55 AM, Vladimir Sementsov-Ogievskiy 
>>> <vsementsov@virtuozzo.com> wrote:
>>> 
>>> 24.05.2021 18:41, Programmingkid wrote:
>>>>> On May 24, 2021, at 6:12 AM, Vladimir Sementsov-Ogievskiy 
>>>>> <vsementsov@virtuozzo.com> wrote:
>>>>> 
>>>>> Hi!
>>>>> 
>>>>> As reported by Programmingkid, command
>>>>> 
>>>>> qemu-system-ppc -usb -device usb-storage,drive=fat16 -drive 
>>>>> file=fat:rw:fat-type=16:"<path of a host 
>>>>> folder>",id=fat16,format=raw,if=none
>>>>> 
>>>>> crashes.
>>>>> 
>>>>> I tested it with qemu-system-x86_64 and it reproduces for me. I even
>>>>> kept "<path of a host folder>" as is :).
>>>>> 
>>>>> So, here are two fixes.
>>>>> 
>>>>> Vladimir Sementsov-Ogievskiy (2):
>>>>>  block/vvfat: child_vvfat_qcow: add .get_parent_aio_context, fix crash
>>>>>  block/vvfat: fix vvfat_child_perm crash
>>>>> 
>>>>> include/block/block.h | 1 +
>>>>> block.c               | 4 ++--
>>>>> block/vvfat.c         | 8 +++-----
>>>>> 3 files changed, 6 insertions(+), 7 deletions(-)
>>>>> 
>>>>> -- 
>>>>> 2.29.2
>>>> I applied both of your patches to the most recent git commit today and 
>>>> they worked. I was able to share files from the host on the guest.
>>>> Thank you.
>>>> Reviewed-by: John Arbuckle <programmingkidx@gmail.com>
>>> 
>>> Thanks for testing! Didn't you mean "Tested-by: "? Or if you both reviewed 
>>> and tested, having both marks makes sense.
>> Yes, you are right. It should be: Tested-by: John Arbuckle 
>> <programmingkidx@gmail.com>
>>> 
>>> Hmm, also, I think "Reported-by" in first patch should be fixed to your 
>>> real name too for consistency.
>> That should be fine but it isn't important.
>> On a related topic would you know if it is possible to use fat32 instead of 
>> fat16 for host folder sharing? I did try replacing the text fat16 with fat32 
>> but it didn't appear to work.
> 
> No, I don't know..
> 
> Moreover, my quick look at the code of vvfat, this fixed bug (which is 
> obviously not covered by tests), and also status of block/vvfat in 
> MAINTAINERS file "Odd Fixes", all this leads to advice "don't use it if 
> possible". May be Kevin can add something about it, he is maintainer..
> 
> Could you use for example NFS or Samba, or sshfs to share folders? Or you 
> need exactly to make a host folder available in guest vm as usb drive?

I do actually need it for some of my VM's. It makes sharing of folder between 
the host and guest so easy.