Re: [Qemu-devel] [PATCH v6 0/7] Rework vhost memory region updates

[Michael S. Tsirkin]

On Tue, Jan 16, 2018 at 06:04:01PM +0000, Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <address@hidden>
> 
> Hi,
>   This patch set reworks the way the vhost code handles changes in
> physical address space layout that came from a discussion with Igor.
> 
> Its intention is to simplify a lot of the update code,
> and to make it easier for the postcopy+shared code to
> do the hugepage alignments that are needed.
> 
> Instead of inserting/removing each section during the add/del
> callbacks of the listener, we start afresh and build a list
> from the add and nop callbacks, then at the end compare the list
> we've built with the exisiting list.
> 
> v6
>   Tidy ups from Igor
>   The biggest change is moving the 'Move log_dirty check' to be
>   the last patch in the set.
> 
> Dr. David Alan Gilbert (7):
>   vhost: Build temporary section list and deref after commit
>   vhost: Simplify ring verification checks
>   vhost: Merge sections added to temporary list
>   vhost: Regenerate region list from changed sections list
>   vhost: Clean out old vhost_set_memory and friends
>   vhost: Merge and delete unused callbacks
>   vhost: Move log_dirty check
> 
>  hw/virtio/trace-events    |   6 +
>  hw/virtio/vhost.c         | 497 
> ++++++++++++++++------------------------------
>  include/hw/virtio/vhost.h |   5 +-
>  3 files changed, 180 insertions(+), 328 deletions(-)


Seems to trigger errors with clang runtime sanitizer:

/scm/qemu/hw/virtio/vhost.c:425:26: runtime error: null pointer passed as 
argument 1, which is declared to never be null
/usr/include/string.h:64:33: note: nonnull attribute specified here
/scm/qemu/hw/virtio/vhost.c:425:45: runtime error: null pointer passed as 
argument 2, which is declared to never be null
/usr/include/string.h:64:33: note: nonnull attribute specified here
/scm/qemu/hw/virtio/vhost.c:425:26: runtime error: null pointer passed as 
argument 1, which is declared to never be null
/usr/include/string.h:64:33: note: nonnull attribute specified here
/scm/qemu/hw/virtio/vhost.c:425:45: runtime error: null pointer passed as 
argument 2, which is declared to never be null
/usr/include/string.h:64:33: note: nonnull attribute specified here
/scm/qemu/hw/virtio/vhost.c:425:26: runtime error: null pointer passed as 
argument 1, which is declared to never be null
/usr/include/string.h:64:33: note: nonnull attribute specified here
/scm/qemu/hw/virtio/vhost.c:425:45: runtime error: null pointer passed as 
argument 2, which is declared to never be null
/usr/include/string.h:64:33: note: nonnull attribute specified here
/scm/qemu/hw/virtio/vhost.c:425:26: runtime error: null pointer passed as 
argument 1, which is declared to never be null
/usr/include/string.h:64:33: note: nonnull attribute specified here
/scm/qemu/hw/virtio/vhost.c:425:45: runtime error: null pointer passed as 
argument 2, which is declared to never be null
/usr/include/string.h:64:33: note: nonnull attribute specified here



> -- 
> 2.14.3