Re: [PATCH] chardev: use remoteAddr if the chardev is client

[Haoqian He <haoqian.he@smartx.com>]

> 2025年2月25日 21:29，Marc-André Lureau <marcandre.lureau@gmail.com> 写道：
> 
> Hi Haoqian
> 
> On Tue, Feb 25, 2025 at 5:19 PM Haoqian He <haoqian.he@smartx.com> wrote:
>> 
>> I use chardev to connect with a vhost-user target, the chardev backend type is
>> socket, part of QEMU boot parameter:
>>  -device vhost-user-blk-pci,chardev=my-vhost-blk-0,id=my-vhost-blk-0,\
>>  bus=pci.1,addr=0x1,bootindex=1,num-queues=4 \
>>  -chardev socket,id=my-vhost-blk-0,path=/tmp/vhost-blk.1
>> 
>> I want to log the chardev’s socket path when socket successfully connected
>> in tcp_chr_connect (chr->filename), but i got "unix:" instead of the expected
>> "unix:/tmp/vhost-blk.1".
>> 
>> The chr->filename was computed from the function qemu_chr_compute_filename,
>> which always return the unix path store by local QIOChannelSocket localAddr.
>> 
>> Unfortunately, the localAddr is obtained via getsockname (see the function
>> qio_channel_socket_set_fd), and according to the man page:
>> "getsockname() returns the current address bound by the socket sockfd".
>> 
>> In this scenario, the socket client's sockfd is unbonded, so the socket
>> filename in localAddr(ss) is NULL.
>> As a solution, we can use remoteAddr(ps) obtained by getpeername (see the
>> function qio_channel_socket_set_fd).
>> 
> 
> thanks a lot, I didn't notice ps != ss in the patch. That makes sense.
> 
> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> 
> 
> 
> -- 
> Marc-André Lureau

Thanks, Lureau.

--
Haoqian