Re: [Qemu-devel] [PATCH 1/3] 9pfs-proxy: simplify error handling

[Michael Tokarev <mjt@tls.msk.ru>]

07.03.2015 23:37, Eric Blake wrote:
> On 03/06/2015 02:43 PM, Michael Tokarev wrote:
>> All filesystem methods that call common v9fs_request() function
>> also convert return value to errno.  Move this conversion to the
>> common function and remove redundand error handling in methods.
> 
> s/redundand/redundant/

Heh.  Is this all that I can say about this patch? ;)

Actually, after reading almost whole 9pfs and fsdev code, I can
say with great confidence this code is nearly hopeless.
Patch 3 shows just one (huge) example.  There are so many issues
with this code, I'm afraid I don't have know the words to express
it.

Again, patch 3 shows a good example.  Another example:

static int v9fs_receive_status(V9fsProxy *proxy,
                               struct iovec *reply, int *status)
...
    proxy_unmarshal(reply, 0, "dd", &header.type, &header.size);
    if (header.size != sizeof(int)) {
        *status = -ENOBUFS;
    }
...
    proxy_unmarshal(reply, PROXY_HDR_SZ, "d", status);

proxy_unmarshall(), for "d" element, expects an int32_t
pointer.  Here we have int pointer, and compare its
size with sizeof(int).  This is a generic problem of whole
v9fs_(un)marshall interface, which is in the core of 9pfs...
this is a status return, which is int32.

Oh well.  I've no idea how this code has been accepted.
It is absolute crap.

/mjt