The patch titled
Subject: mm: remove arch_unmap()
has been added to the -mm mm-unstable branch. Its filename is
mm-remove-arch_unmap.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-remove-arch_unmap.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Subject: mm: remove arch_unmap()
Date: Mon, 12 Aug 2024 18:26:04 +1000
Now that powerpc no longer uses arch_unmap() to handle VDSO unmapping,
there are no meaningful implementions left. Drop support for it entirely,
and update comments which refer to it.
Link: https://lkml.kernel.org/r/20240812082605.743814-3-mpe@xxxxxxxxxxxxxx
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Suggested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Acked-by: David Hildenbrand <david@xxxxxxxxxx>
Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Cc: Jeff Xu <jeffxu@xxxxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Pedro Falcato <pedro.falcato@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/powerpc/include/asm/mmu_context.h | 5 -----
arch/x86/include/asm/mmu_context.h | 5 -----
include/asm-generic/mm_hooks.h | 11 +++--------
mm/mmap.c | 4 +---
mm/vma.c | 8 ++------
5 files changed, 6 insertions(+), 27 deletions(-)
--- a/arch/powerpc/include/asm/mmu_context.h~mm-remove-arch_unmap
+++ a/arch/powerpc/include/asm/mmu_context.h
@@ -260,11 +260,6 @@ static inline void enter_lazy_tlb(struct
extern void arch_exit_mmap(struct mm_struct *mm);
-static inline void arch_unmap(struct mm_struct *mm,
- unsigned long start, unsigned long end)
-{
-}
-
#ifdef CONFIG_PPC_MEM_KEYS
bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write,
bool execute, bool foreign);
--- a/arch/x86/include/asm/mmu_context.h~mm-remove-arch_unmap
+++ a/arch/x86/include/asm/mmu_context.h
@@ -232,11 +232,6 @@ static inline bool is_64bit_mm(struct mm
}
#endif
-static inline void arch_unmap(struct mm_struct *mm, unsigned long start,
- unsigned long end)
-{
-}
-
/*
* We only want to enforce protection keys on the current process
* because we effectively have no access to PKRU for other
--- a/include/asm-generic/mm_hooks.h~mm-remove-arch_unmap
+++ a/include/asm-generic/mm_hooks.h
@@ -1,8 +1,8 @@
/* SPDX-License-Identifier: GPL-2.0 */
/*
- * Define generic no-op hooks for arch_dup_mmap, arch_exit_mmap
- * and arch_unmap to be included in asm-FOO/mmu_context.h for any
- * arch FOO which doesn't need to hook these.
+ * Define generic no-op hooks for arch_dup_mmap and arch_exit_mmap
+ * to be included in asm-FOO/mmu_context.h for any arch FOO which
+ * doesn't need to hook these.
*/
#ifndef _ASM_GENERIC_MM_HOOKS_H
#define _ASM_GENERIC_MM_HOOKS_H
@@ -17,11 +17,6 @@ static inline void arch_exit_mmap(struct
{
}
-static inline void arch_unmap(struct mm_struct *mm,
- unsigned long start, unsigned long end)
-{
-}
-
static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
bool write, bool execute, bool foreign)
{
--- a/mm/mmap.c~mm-remove-arch_unmap
+++ a/mm/mmap.c
@@ -1743,14 +1743,12 @@ int do_vma_munmap(struct vma_iterator *v
struct mm_struct *mm = vma->vm_mm;
/*
- * Check if memory is sealed before arch_unmap.
- * Prevent unmapping a sealed VMA.
+ * Check if memory is sealed, prevent unmapping a sealed VMA.
* can_modify_mm assumes we have acquired the lock on MM.
*/
if (unlikely(!can_modify_mm(mm, start, end)))
return -EPERM;
- arch_unmap(mm, start, end);
return do_vmi_align_munmap(vmi, vma, mm, start, end, uf, unlock);
}
--- a/mm/vma.c~mm-remove-arch_unmap
+++ a/mm/vma.c
@@ -841,7 +841,7 @@ map_count_exceeded:
*
* This function takes a @mas that is either pointing to the previous VMA or set
* to MA_START and sets it up to remove the mapping(s). The @len will be
- * aligned and any arch_unmap work will be preformed.
+ * aligned.
*
* Return: 0 on success and drops the lock if so directed, error and leaves the
* lock held otherwise.
@@ -861,16 +861,12 @@ int do_vmi_munmap(struct vma_iterator *v
return -EINVAL;
/*
- * Check if memory is sealed before arch_unmap.
- * Prevent unmapping a sealed VMA.
+ * Check if memory is sealed, prevent unmapping a sealed VMA.
* can_modify_mm assumes we have acquired the lock on MM.
*/
if (unlikely(!can_modify_mm(mm, start, end)))
return -EPERM;
- /* arch_unmap() might do unmaps itself. */
- arch_unmap(mm, start, end);
-
/* Find the first overlapping VMA */
vma = vma_find(vmi, end);
if (!vma) {
_
Patches currently in -mm which might be from mpe@xxxxxxxxxxxxxx are
mm-add-optional-close-to-struct-vm_special_mapping.patch
powerpc-mm-handle-vdso-unmapping-via-close-rather-than-arch_unmap.patch
mm-remove-arch_unmap.patch
powerpc-vdso-refactor-error-handling.patch
