Re: [Qemu-devel] [PATCH v2 9/9] chardev: tcp: postpone TLS work until machine done

[Paolo Bonzini]

On 07/03/2018 13:40, Daniel P. Berrangé wrote:
> On Wed, Mar 07, 2018 at 12:36:50PM +0000, Daniel P. Berrangé wrote:
>> On Tue, Mar 06, 2018 at 01:33:20PM +0800, Peter Xu wrote:
>>> TLS handshake may create background GSource tasks, while we won't know
>>> the correct GMainContext until the whole chardev (including frontend)
>>> inited.  Let's postpone the initial TLS handshake until machine done.
>>>
>>> For dynamically created tcp chardev, we don't postpone that by checking
>>> the init_machine_done variable.
>>
>> Not sure I see the need for this one - we've already postponed the
>> acceptance of a client in the patch 7.
> 
> Opps, meant to remove this comment, in favour of the later comment - ignore
> this bit.

Since time is ticking for soft freeze, I'll queue the series without
this patch.

Paolo

>>
>>>
>>> Signed-off-by: Peter Xu <address@hidden>
>>> ---
>>>  chardev/char-socket.c | 10 ++++++++++
>>>  1 file changed, 10 insertions(+)
>>>
>>> diff --git a/chardev/char-socket.c b/chardev/char-socket.c
>>> index bd40864f87..997c70dd7d 100644
>>> --- a/chardev/char-socket.c
>>> +++ b/chardev/char-socket.c
>>> @@ -31,6 +31,7 @@
>>>  #include "qemu/option.h"
>>>  #include "qapi/error.h"
>>>  #include "qapi/clone-visitor.h"
>>> +#include "sysemu/sysemu.h"
>>>  
>>>  #include "chardev/char-io.h"
>>>  
>>> @@ -722,6 +723,11 @@ static void tcp_chr_tls_init(Chardev *chr)
>>>      Error *err = NULL;
>>>      gchar *name;
>>>  
>>> +    if (!machine_init_done) {
>>> +        /* This will be postponed to machine_done notifier */
>>> +        return;
>>> +    }
>>> +
>>>      if (s->is_listen) {
>>>          tioc = qio_channel_tls_new_server(
>>>              s->ioc, s->tls_creds,
>>> @@ -1145,6 +1151,10 @@ static int tcp_chr_machine_done_hook(Chardev *chr)
>>>          tcp_chr_connect_async(chr);
>>>      }
>>>  
>>> +    if (s->tls_creds) {
>>> +        tcp_chr_tls_init(chr);
>>> +    }
>>
>> This looks questionable - AFAICT, there's no guarantee we have any
>> client connection active when the machine dnoe hook runs. Only if
>> the chardev is set in client mode, and reconnect_time is *not* set,
>> but this seems to be run unconditionally.
>>
>>
>> Regards,
>> Daniel
>> -- 
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>> :|
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>> :|
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>> :|
>>
> 
> Regards,
> Daniel
>