[merged mm-stable] mm-vma-update-vma_shrink-to-not-pass-start-pgoff-parameters.patch removed from -mm tree

The quilt patch titled
     Subject: mm/vma: update vma_shrink() to not pass start, pgoff parameters
has been removed from the -mm tree.  Its filename was
     mm-vma-update-vma_shrink-to-not-pass-start-pgoff-parameters.patch

This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Lorenzo Stoakes <[email protected]>
Subject: mm/vma: update vma_shrink() to not pass start, pgoff parameters
Date: Fri, 10 Jul 2026 21:17:07 +0100

vma_shrink() is only used by relocate_vma_down() to shrink the tail of a
VMA. Therefore neither the start nor the pgoff parameters make any sense.

It seemed we were passing the pgoff parameter solely to satisfy
vma_set_range()'s requirement for pgoff being specified.

Since vma_set_range() is now isolated to vma.c, we can simply introduce
__vma_set_range() which sets only vma->vm_[start, end], and invoke this
instead, removing start and pgoff from vma_shrink() altogether.

No functional change intended.

Link: https://lore.kernel.org/[email protected]
Signed-off-by: Lorenzo Stoakes <[email protected]>
Reviewed-by: Pedro Falcato <[email protected]>
Reviewed-by: Gregory Price <[email protected]>
Reviewed-by: Vlastimil Babka (SUSE) <[email protected]>
Cc: Ackerley Tng <[email protected]>
Cc: David Hildenbrand (Arm) <[email protected]>
Cc: Kai Huang <[email protected]>
Cc: Marek Szyprowski <[email protected]>
Cc: SJ Park <[email protected]>
Cc: Thomas Zimmermann <[email protected]>
Cc: Liam R. Howlett (Oracle) <[email protected]>
Cc: Zi Yan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---

 mm/vma.c                        |   31 ++++++++++++++++--------------
 mm/vma.h                        |    3 --
 mm/vma_exec.c                   |    2 -
 tools/testing/vma/tests/merge.c |    2 -
 4 files changed, 20 insertions(+), 18 deletions(-)

--- a/mm/vma.c~mm-vma-update-vma_shrink-to-not-pass-start-pgoff-parameters
+++ a/mm/vma.c
@@ -70,11 +70,17 @@ struct mmap_state {
 		.state = VMA_MERGE_START,				\
 	}
 
-static void vma_set_range(struct vm_area_struct *vma, unsigned long start,
-			  unsigned long end, pgoff_t pgoff)
+static void __vma_set_range(struct vm_area_struct *vma, unsigned long start,
+			    unsigned long end)
 {
 	vma->vm_start = start;
 	vma->vm_end = end;
+}
+
+static void vma_set_range(struct vm_area_struct *vma, unsigned long start,
+			  unsigned long end, pgoff_t pgoff)
+{
+	__vma_set_range(vma, start, end);
 	vma->vm_pgoff = pgoff;
 }
 
@@ -1279,27 +1285,24 @@ nomem:
 	return -ENOMEM;
 }
 
-/*
- * vma_shrink() - Reduce an existing VMAs memory area
+/**
+ * vma_shrink() - Shrink the end of a VMA
  * @vmi: The vma iterator
  * @vma: The VMA to modify
- * @start: The new start
  * @end: The new end
  *
+ * Note that the caller may only shrink the end of the VMA.
+ *
  * Returns: 0 on success, -ENOMEM otherwise
  */
 int vma_shrink(struct vma_iterator *vmi, struct vm_area_struct *vma,
-	       unsigned long start, unsigned long end, pgoff_t pgoff)
+	       unsigned long end)
 {
 	struct vma_prepare vp;
 
-	WARN_ON((vma->vm_start != start) && (vma->vm_end != end));
-
-	if (vma->vm_start < start)
-		vma_iter_config(vmi, vma->vm_start, start);
-	else
-		vma_iter_config(vmi, end, vma->vm_end);
+	VM_WARN_ON_ONCE(end > vma->vm_end);
 
+	vma_iter_config(vmi, end, vma->vm_end);
 	if (vma_iter_prealloc(vmi, NULL))
 		return -ENOMEM;
 
@@ -1307,10 +1310,10 @@ int vma_shrink(struct vma_iterator *vmi,
 
 	init_vma_prep(&vp, vma);
 	vma_prepare(&vp);
-	vma_adjust_trans_huge(vma, start, end, NULL);
+	vma_adjust_trans_huge(vma, vma->vm_start, end, NULL);
 
 	vma_iter_clear(vmi);
-	vma_set_range(vma, start, end, pgoff);
+	__vma_set_range(vma, vma->vm_start, end);
 	vma_complete(&vp, vmi, vma->vm_mm);
 	validate_mm(vma->vm_mm);
 	return 0;
--- a/mm/vma_exec.c~mm-vma-update-vma_shrink-to-not-pass-start-pgoff-parameters
+++ a/mm/vma_exec.c
@@ -89,7 +89,7 @@ int relocate_vma_down(struct vm_area_str
 
 	vma_prev(&vmi);
 	/* Shrink the vma to just the new range */
-	return vma_shrink(&vmi, vma, new_start, new_end, vma_start_pgoff(vma));
+	return vma_shrink(&vmi, vma, new_end);
 }
 
 /*
--- a/mm/vma.h~mm-vma-update-vma_shrink-to-not-pass-start-pgoff-parameters
+++ a/mm/vma.h
@@ -297,8 +297,7 @@ void validate_mm(struct mm_struct *mm);
 
 __must_check int vma_expand(struct vma_merge_struct *vmg);
 __must_check int vma_shrink(struct vma_iterator *vmi,
-		struct vm_area_struct *vma,
-		unsigned long start, unsigned long end, pgoff_t pgoff);
+		struct vm_area_struct *vma, unsigned long end);
 
 static inline int vma_iter_store_gfp(struct vma_iterator *vmi,
 			struct vm_area_struct *vma, gfp_t gfp)
--- a/tools/testing/vma/tests/merge.c~mm-vma-update-vma_shrink-to-not-pass-start-pgoff-parameters
+++ a/tools/testing/vma/tests/merge.c
@@ -227,7 +227,7 @@ static bool test_simple_shrink(void)
 
 	ASSERT_FALSE(attach_vma(&mm, vma));
 
-	ASSERT_FALSE(vma_shrink(&vmi, vma, 0, 0x1000, 0));
+	ASSERT_FALSE(vma_shrink(&vmi, vma, 0x1000));
 
 	ASSERT_EQ(vma->vm_start, 0);
 	ASSERT_EQ(vma->vm_end, 0x1000);
_

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

mm-vmalloc-acquire-init_mm-lock-on-huge-vmap-to-avoid-ptdump-uaf.patch
mm-ptdump-always-stabilise-against-page-table-freeing-using-init_mm.patch
arm64-remove-redundant-concurrent-ptdump-uaf-mitigation.patch
mm-huge_memory-fix-huge_zero_pfn-race.patch
mm-huge_memory-separate-out-config_persistent_huge_zero_folio-logic.patch
x86-mm-pat-acquire-init_mm-write-lock-on-collapse-to-avoid-uaf.patch
x86-mm-pat-acquire-init_mm-read-lock-on-attribute-change-to-avoid-uaf.patch
x86-mm-pat-allocate-split-page-tables-as-kernel-page-tables.patch
mm-introduce-vma_flags_can_grow-and-vma_can_grow.patch
mm-vma-update-do_mmap-to-use-vma_flags_t.patch
mm-convert-__get_unmapped_area-to-use-vma_flags_t.patch
mm-update-generic_get_unmapped_area-to-use-vma_flags_t.patch
mm-prefer-mm-def_vma_flags-in-mm-logic.patch
mm-vma-convert-vm_pgprot_modify-to-use-vma_flags_t-and-rename.patch
mm-vma-rename-vma_get_page_prot-to-vma_flags_to_page_prot.patch
mm-introduce-vma_get_page_prot-and-use-it.patch
mm-vma-update-create_init_stack_vma-to-use-vma_flags_t.patch
mm-vma-convert-miscellaneous-uses-of-vma-flags-in-core-mm.patch
mm-mlock-convert-mlock-code-to-use-vma_flags_t.patch
mm-mprotect-convert-mprotect-code-to-use-vma_flags_t.patch
mm-mremap-convert-mremap-code-to-use-vma_flags_t.patch
mm-mseal-remove-superfluous-comments-fix-confusion-around-mm.patch
mm-mseal-limit-scope-of-mseal-address-zero-to-address-zero.patch
mm-mseal-remove-further-superfluous-comments-do_mseal.patch
mm-vma-introduce-vma-virtual-page-offset-field-and-add-helpers.patch
mm-introduce-linear_virt_page_index.patch
mm-abstract-vma_address-and-introduce-vma_anon_address.patch
mm-update-print_bad_page_map-to-show-virtual-page-index.patch
mm-introduce-and-use-vma_filebacked_address.patch
mm-propagate-vma-virtual-page-offset-on-map-remap-split-merge.patch
mm-rmap-track-whether-the-page-vma-mapped-walk-is-anonymous.patch
mm-introduce-and-use-linear_folio_page_index.patch
mm-rmap-use-virt-pgoff-for-map_private-file-backed-anon-folios.patch
tools-testing-vma-expand-vma-merge-tests-to-assert-virt-pgoff.patch
tools-testing-selftests-mm-test-virtual-page-offset-merge-behaviour.patch
mm-vma-only-permit-map_private-dev-zero-to-be-mapped-anonymous.patch
mm-vma-make-map_private-mapped-dev-zero-mappings-truly-anonymous.patch
tools-testing-vma-add-test-to-assert-map_private-dev-zero-is-anon.patch
tools-testing-selftests-mm-add-map_private-dev-zero-merge-tests.patch
mm-add-some-missing-includes-to-mm-local-headers.patch