Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "10 patches.

  Subsystems affected by this patch series: MAINTAINERS and mm (shmem,
  pagealloc, tracing, memcg, memory-failure, vmscan, kfence, and
  hugetlb)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  hugetlb: don't pass page cache pages to restore_reserve_on_error
  kfence: fix is_kfence_address() for addresses below KFENCE_POOL_SIZE
  mm: vmscan: fix missing psi annotation for node_reclaim()
  mm/hwpoison: retry with shake_page() for unhandlable pages
  mm: memcontrol: fix occasional OOMs due to proportional memory.low reclaim
  MAINTAINERS: update ClangBuiltLinux IRC chat
  mmflags.h: add missing __GFP_ZEROTAGS and __GFP_SKIP_KASAN_POISON names
  mm/page_alloc: don't corrupt pcppage_migratetype
  Revert "mm: swap: check if swap backing device is congested or not"
  Revert "mm/shmem: fix shmem_swapin() race with swapoff"

1 files changed, 14 insertions, 5 deletions

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index dfc940d5221d..8ea35ba6699f 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2476,7 +2476,7 @@ void restore_reserve_on_error(struct hstate *h, struct vm_area_struct *vma,
 		if (!rc) {
 			/*
 			 * This indicates there is an entry in the reserve map
-			 * added by alloc_huge_page.  We know it was added
+			 * not added by alloc_huge_page.  We know it was added
 			 * before the alloc_huge_page call, otherwise
 			 * HPageRestoreReserve would be set on the page.
 			 * Remove the entry so that a subsequent allocation
@@ -4660,7 +4660,9 @@ retry_avoidcopy:
 	spin_unlock(ptl);
 	mmu_notifier_invalidate_range_end(&range);
 out_release_all:
-	restore_reserve_on_error(h, vma, haddr, new_page);
+	/* No restore in case of successful pagetable update (Break COW) */
+	if (new_page != old_page)
+		restore_reserve_on_error(h, vma, haddr, new_page);
 	put_page(new_page);
 out_release_old:
 	put_page(old_page);
@@ -4776,7 +4778,7 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
 	pte_t new_pte;
 	spinlock_t *ptl;
 	unsigned long haddr = address & huge_page_mask(h);
-	bool new_page = false;
+	bool new_page, new_pagecache_page = false;
 
 	/*
 	 * Currently, we are forced to kill the process in the event the
@@ -4799,6 +4801,7 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
 		goto out;
 
 retry:
+	new_page = false;
 	page = find_lock_page(mapping, idx);
 	if (!page) {
 		/* Check for page in userfault range */
@@ -4842,6 +4845,7 @@ retry:
 					goto retry;
 				goto out;
 			}
+			new_pagecache_page = true;
 		} else {
 			lock_page(page);
 			if (unlikely(anon_vma_prepare(vma))) {
@@ -4926,7 +4930,9 @@ backout:
 	spin_unlock(ptl);
 backout_unlocked:
 	unlock_page(page);
-	restore_reserve_on_error(h, vma, haddr, page);
+	/* restore reserve for newly allocated pages not in page cache */
+	if (new_page && !new_pagecache_page)
+		restore_reserve_on_error(h, vma, haddr, page);
 	put_page(page);
 	goto out;
 }
@@ -5135,6 +5141,7 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm,
 	int ret = -ENOMEM;
 	struct page *page;
 	int writable;
+	bool new_pagecache_page = false;
 
 	if (is_continue) {
 		ret = -EFAULT;
@@ -5228,6 +5235,7 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm,
 		ret = huge_add_to_page_cache(page, mapping, idx);
 		if (ret)
 			goto out_release_nounlock;
+		new_pagecache_page = true;
 	}
 
 	ptl = huge_pte_lockptr(h, dst_mm, dst_pte);
@@ -5291,7 +5299,8 @@ out_release_unlock:
 	if (vm_shared || is_continue)
 		unlock_page(page);
 out_release_nounlock:
-	restore_reserve_on_error(h, dst_vma, dst_addr, page);
+	if (!new_pagecache_page)
+		restore_reserve_on_error(h, dst_vma, dst_addr, page);
 	put_page(page);
 	goto out;
 }