Re: [Qemu-devel] [PATCH] migration/ram.c: Fix codes conflict about bitmap_mutex

[Zhang, Chen]

Ping~  Anyone have comments about this patch?

Thanks
Zhang Chen


> -----Original Message-----
> From: Wang, Wei W
> Sent: Monday, April 1, 2019 5:12 PM
> To: Zhang, Chen <address@hidden>; Zhang Chen
> <address@hidden>; Dr. David Alan Gilbert <address@hidden>; Juan
> Quintela <address@hidden>; qemu-dev <address@hidden>
> Subject: Re: [PATCH] migration/ram.c: Fix codes conflict about bitmap_mutex
> 
> On 03/30/2019 06:29 AM, Zhang Chen wrote:
> > From: Zhang Chen <address@hidden>
> >
> > I found upstream codes conflict with COLO and lead to crash, and I
> > located to this patch:
> >
> > commit 386a907b37a9321bc5d699bc37104d6ffba1b34d
> > Author: Wei Wang <address@hidden>
> > Date:   Tue Dec 11 16:24:49 2018 +0800
> >
> > migration: use bitmap_mutex in migration_bitmap_clear_dirty
> >
> > My colleague Wei's patch add bitmap_mutex in
> > migration_bitmap_clear_dirty, but COLO didn't initialize the
> > bitmap_mutex. So we always get an error when COLO start up. like that:
> > qemu-system-x86_64: util/qemu-thread-posix.c:64: qemu_mutex_lock_impl:
> Assertion `mutex->initialized' failed.
> >
> > This patch add the bitmap_mutex initialize and destroy in COLO
> > lifecycle.
> >
> > Signed-off-by: Zhang Chen <address@hidden>
> > ---
> >   migration/ram.c | 2 ++
> >   1 file changed, 2 insertions(+)
> >
> > diff --git a/migration/ram.c b/migration/ram.c index
> > d7f8fe45a8..f68beeeeff 100644
> > --- a/migration/ram.c
> > +++ b/migration/ram.c
> > @@ -3918,6 +3918,7 @@ int colo_init_ram_cache(void)
> >       }
> >       ram_state = g_new0(RAMState, 1);
> >       ram_state->migration_dirty_pages = 0;
> > +    qemu_mutex_init(&ram_state->bitmap_mutex);
> >       memory_global_dirty_log_start();
> >
> >       return 0;
> > @@ -3956,6 +3957,7 @@ void colo_release_ram_cache(void)
> >       }
> >
> >       rcu_read_unlock();
> > +    qemu_mutex_destroy(&ram_state->bitmap_mutex);
> >       g_free(ram_state);
> >       ram_state = NULL;
> >   }
> 
> Reviewed-by: Wei Wang <address@hidden>
> 
> Best,
> Wei