Re: [PATCH] qemu-nbd: Close inherited stderr

[Eric Blake <eblake@redhat.com>]

On 5/13/20 2:14 AM, Raphael Pour wrote:
> On 5/12/20 3:57 PM, Eric Blake wrote:
>> Wouldn't it just be simpler to not dup in the first place?
>>
>> diff --git i/qemu-nbd.c w/qemu-nbd.c
>> index 4aa005004ebd..6ba2544feb3a 100644
>> --- i/qemu-nbd.c
>> +++ w/qemu-nbd.c
>> @@ -916,7 +916,9 @@ int main(int argc, char **argv)
>>           } else if (pid == 0) {
>>               close(stderr_fd[0]);
>>
>> -            old_stderr = dup(STDERR_FILENO);
>> +            if (fork_process) {
>> +                old_stderr = dup(STDERR_FILENO);
>> +            }
>>               ret = qemu_daemon(1, 0);
>>
>>               /* Temporarily redirect stderr to the parent's pipe...  */
> 
> Yes, you're right. We tested your patch and it also fixes the unwanted
> open stderr.
> 
> Could you consider this patch in one of the next releases?

Yes, now that we know about it, the bug will be fixed in 5.1; we can 
also cc: qemu-stable to get it backported to the next 5.0.x release 
(downstream developers are also more likely to backport it to their 
ports as well if it lands on qemu-stable).  Would you like to try your 
hand at a v2 patch, or shall I just turn my proposal into a formal patch 
and mention you as the reporter?  Time-wise, it may be faster for me to 
just take over the patch than to spend the time coaching you through to 
the point of your first successful submission, but project-wise, it is 
always better to welcome in new contributors and share the wealth, 
rather than making maintainers become the bottleneck.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
Virtualization:  qemu.org | libvirt.org