On Mon, 2019-09-09 at 10:59 +0200, David Hildenbrand wrote: > On 07.09.19 19:26, Alexander Duyck wrote: > > From: Alexander Duyck <[email protected]> > > > > Currently the page poisoning setting wasn't being enabled unless free page > > hinting was enabled. However we will need the page poisoning tracking logic > > as well for unused page reporting. As such pull it out and make it a > > separate bit of config in the probe function. > > > > In addition we can actually wrap the code in a check for NO_SANITY. If we > > don't care what is actually in the page we can just default to 0 and leave > > it there. > > > > Signed-off-by: Alexander Duyck <[email protected]> > > --- > > drivers/virtio/virtio_balloon.c | 22 +++++++++++++++------- > > 1 file changed, 15 insertions(+), 7 deletions(-) > > > > diff --git a/drivers/virtio/virtio_balloon.c > > b/drivers/virtio/virtio_balloon.c > > index 226fbb995fb0..d2547df7de93 100644 > > --- a/drivers/virtio/virtio_balloon.c > > +++ b/drivers/virtio/virtio_balloon.c > > @@ -842,7 +842,6 @@ static int virtio_balloon_register_shrinker(struct > > virtio_balloon *vb) > > static int virtballoon_probe(struct virtio_device *vdev) > > { > > struct virtio_balloon *vb; > > - __u32 poison_val; > > int err; > > > > if (!vdev->config->get) { > > @@ -909,11 +908,18 @@ static int virtballoon_probe(struct virtio_device > > *vdev) > > VIRTIO_BALLOON_CMD_ID_STOP); > > spin_lock_init(&vb->free_page_list_lock); > > INIT_LIST_HEAD(&vb->free_page_list); > > - if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON)) { > > - memset(&poison_val, PAGE_POISON, sizeof(poison_val)); > > - virtio_cwrite(vb->vdev, struct virtio_balloon_config, > > - poison_val, &poison_val); > > - } > > + } > > + if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON)) { > > + __u32 poison_val; > > + > > + /* > > + * Let hypervisor know that we are expecting a specific > > + * value to be written back in unused pages. > > + */ > > "Let the hypervisor know" ... ? > > > + memset(&poison_val, PAGE_POISON, sizeof(poison_val)); > > + > > + virtio_cwrite(vb->vdev, struct virtio_balloon_config, > > + poison_val, &poison_val); > > } > > /* > > * We continue to use VIRTIO_BALLOON_F_DEFLATE_ON_OOM to decide if a > > @@ -1014,7 +1020,9 @@ static int virtballoon_restore(struct virtio_device > > *vdev) > > > > static int virtballoon_validate(struct virtio_device *vdev) > > { > > - if (!page_poisoning_enabled()) > > + /* Notify host if we care about poison value */ > > "Tell the host whether we care about poisoned pages." ? > > > + if (IS_ENABLED(CONFIG_PAGE_POISONING_NO_SANITY) || > > + !page_poisoning_enabled()) > > __virtio_clear_bit(vdev, VIRTIO_BALLOON_F_PAGE_POISON); > > > > __virtio_clear_bit(vdev, VIRTIO_F_IOMMU_PLATFORM); > > > > Reviewed-by: David Hildenbrand <[email protected]> >
Thanks. I will update the comments for v10. - Alex
