On Mon, Sep 26, 2022, Ricardo Koller wrote:
> On Thu, Sep 22, 2022 at 07:32:42PM +0000, Sean Christopherson wrote:
> > On Thu, Sep 22, 2022, Ricardo Koller wrote:
> > > + void *hva = (void *)region->region.userspace_addr;
> > > + uint64_t paging_size = region->region.memory_size;
> > > + int ret, fd = region->fd;
> > > +
> > > + if (fd != -1) {
> > > + ret = fallocate(fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
> > > + 0, paging_size);
> > > + TEST_ASSERT(ret == 0, "fallocate failed, errno: %d\n", errno);
> > > + } else {
> > > + if (is_backing_src_hugetlb(region->backing_src_type))
> > > + return false;
> >
> > Why is hugetlb disallowed? I thought anon hugetlb supports MADV_DONTNEED?
> >
>
> It fails with EINVAL (only tried on arm) for both the PAGE_SIZE and the huge
> page size. And note that the address is aligned as well.
>
> madvise(0xffffb7c00000, 2097152, MADV_DONTNEED) = -1 EINVAL (Invalid argument)
> ^^^^^^^^^^^^^^ ^^^^^^^
> 2M aligned 2M (hugepage size)
>
> madvise(0xffff9e800000, 4096, MADV_DONTNEED) = -1 EINVAL (Invalid argument)
> ^^^^
> PAGE_SIZE
I think this needs to be root caused before merging. Unless I'm getting turned
around, MADV_DONTEED should work, i.e. there is a test bug lurking somewhere.
