Merge tag 'mm-stable-2022-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull more MM updates from Andrew Morton:

 - fix a race which causes page refcounting errors in ZONE_DEVICE pages
   (Alistair Popple)

 - fix userfaultfd test harness instability (Peter Xu)

 - various other patches in MM, mainly fixes

* tag 'mm-stable-2022-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (29 commits)
  highmem: fix kmap_to_page() for kmap_local_page() addresses
  mm/page_alloc: fix incorrect PGFREE and PGALLOC for high-order page
  mm/selftest: uffd: explain the write missing fault check
  mm/hugetlb: use hugetlb_pte_stable in migration race check
  mm/hugetlb: fix race condition of uffd missing/minor handling
  zram: always expose rw_page
  LoongArch: update local TLB if PTE entry exists
  mm: use update_mmu_tlb() on the second thread
  kasan: fix array-bounds warnings in tests
  hmm-tests: add test for migrate_device_range()
  nouveau/dmem: evict device private memory during release
  nouveau/dmem: refactor nouveau_dmem_fault_copy_one()
  mm/migrate_device.c: add migrate_device_range()
  mm/migrate_device.c: refactor migrate_vma and migrate_deivce_coherent_page()
  mm/memremap.c: take a pgmap reference on page allocation
  mm: free device private pages have zero refcount
  mm/memory.c: fix race when faulting a device private page
  mm/damon: use damon_sz_region() in appropriate place
  mm/damon: move sz_damon_region to damon_sz_region
  lib/test_meminit: add checks for the allocation functions
  ...

2 files changed, 12 insertions, 18 deletions

diff --git a/mm/damon/core.c b/mm/damon/core.c
index 8e1ab38d0f1f..36d098d06c55 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -491,7 +491,7 @@ static unsigned long damon_region_sz_limit(struct damon_ctx *ctx)
 
 	damon_for_each_target(t, ctx) {
 		damon_for_each_region(r, t)
-			sz += r->ar.end - r->ar.start;
+			sz += damon_sz_region(r);
 	}
 
 	if (ctx->attrs.min_nr_regions)
@@ -674,7 +674,7 @@ static bool __damos_valid_target(struct damon_region *r, struct damos *s)
 {
 	unsigned long sz;
 
-	sz = r->ar.end - r->ar.start;
+	sz = damon_sz_region(r);
 	return s->pattern.min_sz_region <= sz &&
 		sz <= s->pattern.max_sz_region &&
 		s->pattern.min_nr_accesses <= r->nr_accesses &&
@@ -702,7 +702,7 @@ static void damon_do_apply_schemes(struct damon_ctx *c,
 
 	damon_for_each_scheme(s, c) {
 		struct damos_quota *quota = &s->quota;
-		unsigned long sz = r->ar.end - r->ar.start;
+		unsigned long sz = damon_sz_region(r);
 		struct timespec64 begin, end;
 		unsigned long sz_applied = 0;
 
@@ -731,14 +731,14 @@ static void damon_do_apply_schemes(struct damon_ctx *c,
 				sz = ALIGN_DOWN(quota->charge_addr_from -
 						r->ar.start, DAMON_MIN_REGION);
 				if (!sz) {
-					if (r->ar.end - r->ar.start <=
-							DAMON_MIN_REGION)
+					if (damon_sz_region(r) <=
+					    DAMON_MIN_REGION)
 						continue;
 					sz = DAMON_MIN_REGION;
 				}
 				damon_split_region_at(t, r, sz);
 				r = damon_next_region(r);
-				sz = r->ar.end - r->ar.start;
+				sz = damon_sz_region(r);
 			}
 			quota->charge_target_from = NULL;
 			quota->charge_addr_from = 0;
@@ -843,8 +843,7 @@ static void kdamond_apply_schemes(struct damon_ctx *c)
 					continue;
 				score = c->ops.get_scheme_score(
 						c, t, r, s);
-				quota->histogram[score] +=
-					r->ar.end - r->ar.start;
+				quota->histogram[score] += damon_sz_region(r);
 				if (score > max_score)
 					max_score = score;
 			}
@@ -865,18 +864,13 @@ static void kdamond_apply_schemes(struct damon_ctx *c)
 	}
 }
 
-static inline unsigned long sz_damon_region(struct damon_region *r)
-{
-	return r->ar.end - r->ar.start;
-}
-
 /*
  * Merge two adjacent regions into one region
  */
 static void damon_merge_two_regions(struct damon_target *t,
 		struct damon_region *l, struct damon_region *r)
 {
-	unsigned long sz_l = sz_damon_region(l), sz_r = sz_damon_region(r);
+	unsigned long sz_l = damon_sz_region(l), sz_r = damon_sz_region(r);
 
 	l->nr_accesses = (l->nr_accesses * sz_l + r->nr_accesses * sz_r) /
 			(sz_l + sz_r);
@@ -905,7 +899,7 @@ static void damon_merge_regions_of(struct damon_target *t, unsigned int thres,
 
 		if (prev && prev->ar.end == r->ar.start &&
 		    abs(prev->nr_accesses - r->nr_accesses) <= thres &&
-		    sz_damon_region(prev) + sz_damon_region(r) <= sz_limit)
+		    damon_sz_region(prev) + damon_sz_region(r) <= sz_limit)
 			damon_merge_two_regions(t, prev, r);
 		else
 			prev = r;
@@ -963,7 +957,7 @@ static void damon_split_regions_of(struct damon_target *t, int nr_subs)
 	int i;
 
 	damon_for_each_region_safe(r, next, t) {
-		sz_region = r->ar.end - r->ar.start;
+		sz_region = damon_sz_region(r);
 
 		for (i = 0; i < nr_subs - 1 &&
 				sz_region > 2 * DAMON_MIN_REGION; i++) {
diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c
index ea94e0b2c311..15f03df66db6 100644
--- a/mm/damon/vaddr.c
+++ b/mm/damon/vaddr.c
@@ -72,7 +72,7 @@ static int damon_va_evenly_split_region(struct damon_target *t,
 		return -EINVAL;
 
 	orig_end = r->ar.end;
-	sz_orig = r->ar.end - r->ar.start;
+	sz_orig = damon_sz_region(r);
 	sz_piece = ALIGN_DOWN(sz_orig / nr_pieces, DAMON_MIN_REGION);
 
 	if (!sz_piece)
@@ -618,7 +618,7 @@ static unsigned long damos_madvise(struct damon_target *target,
 {
 	struct mm_struct *mm;
 	unsigned long start = PAGE_ALIGN(r->ar.start);
-	unsigned long len = PAGE_ALIGN(r->ar.end - r->ar.start);
+	unsigned long len = PAGE_ALIGN(damon_sz_region(r));
 	unsigned long applied;
 
 	mm = damon_get_mm(target);