[v3] block: fix 'savevm' hang with -object iothread

[Qemu-devel] [PATCH v3 0/4] block: fix 'savevm' hang with -object iothread

Posted by Stefan Hajnoczi 6 years, 11 months ago

v3:
 * Add missing bdrv_drain_all_end() in error code paths [Kevin]
v2:
 * New patch to use bdrv_drain_all_begin/end() in savevm/loadvm [Kevin]
   (All other patches unchanged)

The 'savevm' command hangs when -object iothread is used.  See patches for
details, but basically the vmstate read/write code didn't conform to the latest
block layer locking rules.

Stefan Hajnoczi (4):
  block: count bdrv_co_rw_vmstate() requests
  block: use BDRV_POLL_WHILE() in bdrv_rw_vmstate()
  migration: avoid recursive AioContext locking in save_vmstate()
  migration: use bdrv_drain_all_begin/end() instead bdrv_drain_all()

 block/io.c         | 21 +++++++++++++--------
 migration/savevm.c | 30 ++++++++++++++++++++++++++----
 2 files changed, 39 insertions(+), 12 deletions(-)

-- 
2.9.3

Re: [Qemu-devel] [Qemu-block] [PATCH v3 0/4] block: fix 'savevm' hang with -object iothread

Posted by Stefan Hajnoczi 6 years, 10 months ago

On Mon, May 22, 2017 at 02:57:00PM +0100, Stefan Hajnoczi wrote:
> v3:
>  * Add missing bdrv_drain_all_end() in error code paths [Kevin]
> v2:
>  * New patch to use bdrv_drain_all_begin/end() in savevm/loadvm [Kevin]
>    (All other patches unchanged)
> 
> The 'savevm' command hangs when -object iothread is used.  See patches for
> details, but basically the vmstate read/write code didn't conform to the latest
> block layer locking rules.
> 
> Stefan Hajnoczi (4):
>   block: count bdrv_co_rw_vmstate() requests
>   block: use BDRV_POLL_WHILE() in bdrv_rw_vmstate()
>   migration: avoid recursive AioContext locking in save_vmstate()
>   migration: use bdrv_drain_all_begin/end() instead bdrv_drain_all()
> 
>  block/io.c         | 21 +++++++++++++--------
>  migration/savevm.c | 30 ++++++++++++++++++++++++++----
>  2 files changed, 39 insertions(+), 12 deletions(-)

Ping

Re: [Qemu-devel] [Qemu-block] [PATCH v3 0/4] block: fix 'savevm' hang with -object iothread

Posted by Stefan Hajnoczi 6 years, 10 months ago

On Mon, May 22, 2017 at 02:57:00PM +0100, Stefan Hajnoczi wrote:
> v3:
>  * Add missing bdrv_drain_all_end() in error code paths [Kevin]
> v2:
>  * New patch to use bdrv_drain_all_begin/end() in savevm/loadvm [Kevin]
>    (All other patches unchanged)
> 
> The 'savevm' command hangs when -object iothread is used.  See patches for
> details, but basically the vmstate read/write code didn't conform to the latest
> block layer locking rules.
> 
> Stefan Hajnoczi (4):
>   block: count bdrv_co_rw_vmstate() requests
>   block: use BDRV_POLL_WHILE() in bdrv_rw_vmstate()
>   migration: avoid recursive AioContext locking in save_vmstate()
>   migration: use bdrv_drain_all_begin/end() instead bdrv_drain_all()
> 
>  block/io.c         | 21 +++++++++++++--------
>  migration/savevm.c | 30 ++++++++++++++++++++++++++----
>  2 files changed, 39 insertions(+), 12 deletions(-)

Ping ^ 2

Stefan

Re: [Qemu-devel] [Qemu-block] [PATCH v3 0/4] block: fix 'savevm' hang with -object iothread

Posted by Kevin Wolf 6 years, 10 months ago

Am 12.06.2017 um 15:47 hat Stefan Hajnoczi geschrieben:
> On Mon, May 22, 2017 at 02:57:00PM +0100, Stefan Hajnoczi wrote:
> > v3:
> >  * Add missing bdrv_drain_all_end() in error code paths [Kevin]
> > v2:
> >  * New patch to use bdrv_drain_all_begin/end() in savevm/loadvm [Kevin]
> >    (All other patches unchanged)
> > 
> > The 'savevm' command hangs when -object iothread is used.  See patches for
> > details, but basically the vmstate read/write code didn't conform to the latest
> > block layer locking rules.
> > 
> > Stefan Hajnoczi (4):
> >   block: count bdrv_co_rw_vmstate() requests
> >   block: use BDRV_POLL_WHILE() in bdrv_rw_vmstate()
> >   migration: avoid recursive AioContext locking in save_vmstate()
> >   migration: use bdrv_drain_all_begin/end() instead bdrv_drain_all()
> > 
> >  block/io.c         | 21 +++++++++++++--------
> >  migration/savevm.c | 30 ++++++++++++++++++++++++++----
> >  2 files changed, 39 insertions(+), 12 deletions(-)
> 
> Ping ^ 2

Thanks, applied to the block branch.

Kevin