Message ID | 20170411075457.28020-1-aik@ozlabs.ru (mailing list archive) |
---|---|
State | Accepted |
Commit | e889e96e98e8da97bd39e46b7253615eabe14397 |
Headers | show |
On Tue, 2017-04-11 at 17:54 +1000, Alexey Kardashevskiy wrote: > The CMA pages migration code does not support compound pages at > the moment so it performs few tests before proceeding to actual page > migration. > > One of the tests - PageTransHuge() - has VM_BUG_ON_PAGE(PageTail()) as > it is designed to be called on head pages only. Since we also test for > PageCompound(), and it contains PageTail() and PageHead(), we can > simplify the check by leaving just PageCompound() and therefore avoid > possible VM_BUG_ON_PAGE. > > Fixes: 2e5bbb5461f1 ("KVM: PPC: Book3S HV: Migrate pinned pages out of CMA") > Cc: stable@vger.kernel.org # v4.9+ > Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> > Acked-by: Balbir Singh <bsingharora@gmail.com> > --- > > Changes: > v2: > * instead of moving PageCompound() to the beginning, this just drops > PageHuge() and PageTransHuge() > Looks good! My Acked-by is already present Balbir Singh.
On Tue, 2017-04-11 at 07:54:57 UTC, Alexey Kardashevskiy wrote: > The CMA pages migration code does not support compound pages at > the moment so it performs few tests before proceeding to actual page > migration. > > One of the tests - PageTransHuge() - has VM_BUG_ON_PAGE(PageTail()) as > it is designed to be called on head pages only. Since we also test for > PageCompound(), and it contains PageTail() and PageHead(), we can > simplify the check by leaving just PageCompound() and therefore avoid > possible VM_BUG_ON_PAGE. > > Fixes: 2e5bbb5461f1 ("KVM: PPC: Book3S HV: Migrate pinned pages out of CMA") > Cc: stable@vger.kernel.org # v4.9+ > Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> > Acked-by: Balbir Singh <bsingharora@gmail.com> Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/e889e96e98e8da97bd39e46b725361 cheers
diff --git a/arch/powerpc/mm/mmu_context_iommu.c b/arch/powerpc/mm/mmu_context_iommu.c index 497130c5c742..96f835cbf212 100644 --- a/arch/powerpc/mm/mmu_context_iommu.c +++ b/arch/powerpc/mm/mmu_context_iommu.c @@ -81,7 +81,7 @@ struct page *new_iommu_non_cma_page(struct page *page, unsigned long private, gfp_t gfp_mask = GFP_USER; struct page *new_page; - if (PageHuge(page) || PageTransHuge(page) || PageCompound(page)) + if (PageCompound(page)) return NULL; if (PageHighMem(page)) @@ -100,7 +100,7 @@ static int mm_iommu_move_page_from_cma(struct page *page) LIST_HEAD(cma_migrate_pages); /* Ignore huge pages for now */ - if (PageHuge(page) || PageTransHuge(page) || PageCompound(page)) + if (PageCompound(page)) return -EBUSY; lru_add_drain();