RE: [PATCH v3 2/2] virtio_balloon: replace oom notifier with shrinker

From: Wang, Wei W
Date: Mon Aug 06 2018 - 08:46:08 EST


On Monday, August 6, 2018 6:29 PM, Tetsuo Handa wrote:
> On 2018/08/06 18:56, Wei Wang wrote:
> > On 08/03/2018 08:11 PM, Tetsuo Handa wrote:
> >> On 2018/08/03 17:32, Wei Wang wrote:
> >>> +static int virtio_balloon_register_shrinker(struct virtio_balloon
> >>> +*vb) {
> >>> +ÂÂÂ vb->shrinker.scan_objects = virtio_balloon_shrinker_scan;
> >>> +ÂÂÂ vb->shrinker.count_objects = virtio_balloon_shrinker_count;
> >>> +ÂÂÂ vb->shrinker.batch = 0;
> >>> +ÂÂÂ vb->shrinker.seeks = DEFAULT_SEEKS;
> >> Why flags field is not set? If vb is allocated by kmalloc(GFP_KERNEL)
> >> and is nowhere zero-cleared, KASAN would complain it.
> >
> > Could you point where in the code that would complain it?
> > I only see two shrinker flags (NUMA_AWARE and MEMCG_AWARE), and
> they seem not related to that.
>
> Where is vb->shrinker.flags initialized?

Is that mandatory to be initialized? I find it's not initialized in most shrinkers (e.g. zs_register_shrinker, huge_zero_page_shrinker).

Best,
Wei