Re: [Qemu-devel] [PATCH v2 1/1] qemu/migration: fix the double free problem on from_src_file

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* QingFeng Hao (haoqf@linux.vnet.ibm.com) wrote:
> 
> 
> 在 2017/6/6 20:49, Kevin Wolf 写道:
> > Am 06.06.2017 um 07:24 hat QingFeng Hao geschrieben:

<snip>

> > I can't tell for postcopy_ram_listen_thread() - commit 660819b didn't
> > seem to remove a qemu_fclose() call there, but I can't see one left
> > behind either. Was the file leaked before commit 660819b or am I
> > missing something?
> I don't think so because loadvm_postcopy_handle_listen creates thread
> postcopy_ram_listen_thread
> and passes mis->from_src_file as its arg, which will be closed by
> migration_incoming_state_destroy.
> What confuses me is in the series function calls of qemu_loadvm_state_main
> etc, argument f looks
> to be redundant as mis already contains from_src_file which equals to f.

In postcopy qemu_loadvm_state_main is called with two different file
arguments but the same mis argument;  see loadvm_handle_cmd_packaged for
the other case where it's called on a packaged-file blob.

> Furthermore, mis may be
> also redundant as it can be got via migration_incoming_get_current. Thanks!

We keep changing our minds about the preferred style.  Sometimes we
think it's best to pass the pointer, sometimes we think it's best
to call get_current.

Dave

> > 
> > Kevin
> > 
> 
> -- 
> Regards
> QingFeng Hao
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK