Currently migrate_vma_setup() zeros both src and dst pfn arrays. This means it is not possible to pass per-pfn flags to migrate_vma_setup(). A future patch introduces per-pfn flags for migrate_vma_setup(), so ensure existing callers will not be affected by having the caller zero both src and dst pfn arrays.
Signed-off-by: Alistair Popple apopple@nvidia.com --- arch/powerpc/kvm/book3s_hv_uvmem.c | 4 ++-- lib/test_hmm.c | 6 ++++-- mm/migrate.c | 1 - 3 files changed, 6 insertions(+), 5 deletions(-)
diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_hv_uvmem.c index 84e5a2dc8be5..d434783b272a 100644 --- a/arch/powerpc/kvm/book3s_hv_uvmem.c +++ b/arch/powerpc/kvm/book3s_hv_uvmem.c @@ -506,7 +506,7 @@ static int __kvmppc_svm_page_out(struct vm_area_struct *vma, unsigned long end, unsigned long page_shift, struct kvm *kvm, unsigned long gpa) { - unsigned long src_pfn, dst_pfn = 0; + unsigned long src_pfn = 0, dst_pfn = 0; struct migrate_vma mig; struct page *dpage, *spage; struct kvmppc_uvmem_page_pvt *pvt; @@ -732,7 +732,7 @@ static int kvmppc_svm_page_in(struct vm_area_struct *vma, unsigned long page_shift, bool pagein) { - unsigned long src_pfn, dst_pfn = 0; + unsigned long src_pfn = 0, dst_pfn = 0; struct migrate_vma mig; struct page *spage; unsigned long pfn; diff --git a/lib/test_hmm.c b/lib/test_hmm.c index 80a78877bd93..98848b96ff09 100644 --- a/lib/test_hmm.c +++ b/lib/test_hmm.c @@ -696,6 +696,8 @@ static int dmirror_migrate(struct dmirror *dmirror, if (next > vma->vm_end) next = vma->vm_end;
+ memset(src_pfns, 0, ARRAY_SIZE(src_pfns)); + memset(dst_pfns, 0, ARRAY_SIZE(dst_pfns)); args.vma = vma; args.src = src_pfns; args.dst = dst_pfns; @@ -1025,8 +1027,8 @@ static vm_fault_t dmirror_devmem_fault_alloc_and_copy(struct migrate_vma *args, static vm_fault_t dmirror_devmem_fault(struct vm_fault *vmf) { struct migrate_vma args; - unsigned long src_pfns; - unsigned long dst_pfns; + unsigned long src_pfns = 0; + unsigned long dst_pfns = 0; struct page *rpage; struct dmirror *dmirror; vm_fault_t ret; diff --git a/mm/migrate.c b/mm/migrate.c index 053228559fd3..fe8bb322e2e3 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2874,7 +2874,6 @@ int migrate_vma_setup(struct migrate_vma *args) if (!args->src || !args->dst) return -EINVAL;
- memset(args->src, 0, sizeof(*args->src) * nr_pages); args->cpages = 0; args->npages = 0;