+ mm-hmmc-fix-build-with-config_mmu_notifier=n.patch added to mm-unstable branch

The patch titled
     Subject: mm/hmm.c: fix build with CONFIG_MMU_NOTIFIER=n
has been added to the -mm mm-unstable branch.  Its filename is
     mm-hmmc-fix-build-with-config_mmu_notifier=n.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-hmmc-fix-build-with-config_mmu_notifier=n.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Andrew Morton <[email protected]>
Subject: mm/hmm.c: fix build with CONFIG_MMU_NOTIFIER=n
Date: Sat Jul 25 07:12:21 PM PDT 2026

With microblaze
https://download.01.org/0day-ci/archive/20260702/[email protected]/config
(CONFIG_MMU_NOTIFIER=n):

mm/hmm.c: In function 'hmm_range_fault_unlocked_timeout':
mm/hmm.c:804:25: error: implicit declaration of function 'mmu_interval_read_begin'; did you mean 'mmu_interval_check_retry'? [-Wimplicit-function-declaration]
  804 |                         mmu_interval_read_begin(range->notifier);
      |                         ^~~~~~~~~~~~~~~~~~~~~~~
      |                         mmu_interval_check_retry


Cc: Stanislav Kinsburskii <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Leon Romanovsky <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---

 include/linux/mmu_notifier.h |   13 +++++++++++++
 1 file changed, 13 insertions(+)

--- a/include/linux/mmu_notifier.h~mm-hmmc-fix-build-with-config_mmu_notifier=n
+++ a/include/linux/mmu_notifier.h
@@ -576,6 +576,19 @@ static inline void _mmu_notifier_range_i
 	_mmu_notifier_range_init(range, start, end)
 
 static inline bool
+mmu_interval_check_retry(struct mmu_interval_notifier *interval_sub,
+			 unsigned long seq)
+{
+	return true;
+}
+
+static inline unsigned long
+mmu_interval_read_begin(struct mmu_interval_notifier *interval_sub)
+{
+	return 0;
+}
+
+static inline bool
 mmu_notifier_range_blockable(const struct mmu_notifier_range *range)
 {
 	return true;
_

Patches currently in -mm which might be from [email protected] are

mm-mincore-use-walk_page_range_vma-in-do_mincore-fix.patch
csky-implement-flush_cache_vmap-in-c.patch
mm-annotate-data-race-in-cpu_needs_drain-fix.patch
mm-zsmalloc-encode-class-index-in-obj-value-for-lockless-class-lookup-fix.patch
mm-zsmalloc-drop-pool-lock-from-zs_free-on-64-bit-systems-fix.patch
mm-zsmalloc-drop-pool-lock-from-zs_free-on-64-bit-systems-fix-fix.patch
mm-rmap-use-huge_ptep_get-in-try_to_migrate_one-checkpatch-fixes.patch
mm-mprotect-use-huge_ptep_get-for-hugetlb-fix.patch
mm-drop-stale-folio_ref_count==1-check-in-do_swap_page-reuse-logic-fix.patch
alloc_tag-add-ioctl-to-proc-allocinfo-fix.patch
mm-hmmc-fix-build-with-config_mmu_notifier=n.patch
mm-vma-add-and-use-vma__pgoff-fix.patch
drivers-media-v4l2-core-v4l2-vp9c-reduce-inlining.patch