On Fri, Sep 25, 2020 at 01:44:42PM -0700, Ralph Campbell wrote: > ZONE_DEVICE struct pages have an extra reference count that complicates the > code for put_page() and several places in the kernel that need to check the > reference count to see that a page is not being used (gup, compaction, > migration, etc.). Clean up the code so the reference count doesn't need to > be treated specially for ZONE_DEVICE. > > Signed-off-by: Ralph Campbell <rcampbell@xxxxxxxxxx> > --- > arch/powerpc/kvm/book3s_hv_uvmem.c | 2 +- > drivers/gpu/drm/nouveau/nouveau_dmem.c | 2 +- > include/linux/dax.h | 2 +- > include/linux/memremap.h | 7 ++- > include/linux/mm.h | 44 -------------- > lib/test_hmm.c | 2 +- > mm/gup.c | 44 -------------- > mm/internal.h | 8 +++ > mm/memremap.c | 82 ++++++-------------------- > mm/migrate.c | 5 -- > mm/page_alloc.c | 3 + > mm/swap.c | 46 +++------------ > 12 files changed, 44 insertions(+), 203 deletions(-) > > diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_hv_uvmem.c > index 7705d5557239..e6ec98325fab 100644 > --- a/arch/powerpc/kvm/book3s_hv_uvmem.c > +++ b/arch/powerpc/kvm/book3s_hv_uvmem.c > @@ -711,7 +711,7 @@ static struct page *kvmppc_uvmem_get_page(unsigned long gpa, struct kvm *kvm) > > dpage = pfn_to_page(uvmem_pfn); > dpage->zone_device_data = pvt; > - get_page(dpage); > + init_page_count(dpage); The powerpc change looks good. Passes a quick sanity test of booting/rebooting a secure guest on Power. Tested-by: Bharata B Rao <bharata@xxxxxxxxxxxxx> Regards, Bharata.