* Michael S. Tsirkin ([email protected]) wrote:
> On Tue, Jan 16, 2018 at 06:04:01PM +0000, Dr. David Alan Gilbert (git) wrote:
> > From: "Dr. David Alan Gilbert" <[email protected]>
> >
> > 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
How are you running that test? Can you add this printf and tell me what
it's seeing?
/* Same size, lets check the contents */
fprintf(stderr, "%s: %p %p %d\n", __func__, dev->mem_sections,
old_sections, n_old_sections);
changed = memcmp(dev->mem_sections, old_sections,
n_old_sections * sizeof(old_sections[0])) != 0;
I'm seeing a bunch of calls where both pointers are NULL, but
n_old_sections is 0, which feels legal to me.
I guess we could make it:
changed = n_old_sections ? memcmp(....) : false;
just to shut clang up.
Dave
>
>
> > --
> > 2.14.3
--
Dr. David Alan Gilbert / [email protected] / Manchester, UK
