The patch titled
Subject: Fix for "mm: handle faults that merely update the accessed bit under the VMA lock"
has been added to the -mm mm-unstable branch. Its filename is
mm-handle-faults-that-merely-update-the-accessed-bit-under-the-vma-lock-fix.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-handle-faults-that-merely-update-the-accessed-bit-under-the-vma-lock-fix.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: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Subject: Fix for "mm: handle faults that merely update the accessed bit under the VMA lock"
Date: Thu, 27 Jul 2023 21:06:36 +0100
address "suspicious RCU usage" warning
Link: https://lkml.kernel.org/r/ZMK7jwpI4uD6tKrF@xxxxxxxxxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memory.c | 6 ++++++
1 file changed, 6 insertions(+)
--- a/mm/memory.c~mm-handle-faults-that-merely-update-the-accessed-bit-under-the-vma-lock-fix
+++ a/mm/memory.c
@@ -3445,6 +3445,12 @@ reuse:
return 0;
}
copy:
+ if ((vmf->flags & FAULT_FLAG_VMA_LOCK) && !vma->anon_vma) {
+ pte_unmap_unlock(vmf->pte, vmf->ptl);
+ vma_end_read(vmf->vma);
+ return VM_FAULT_RETRY;
+ }
+
/*
* Ok, we need to copy. Oh, well..
*/
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-drop-per-vma-lock-when-returning-vm_fault_retry-or-vm_fault_completed-fix.patch
rmap-pass-the-folio-to-__page_check_anon_rmap.patch
highmem-add-memcpy_to_folio-and-memcpy_from_folio.patch
affs-convert-affs_symlink_read_folio-to-use-the-folio.patch
affs-convert-data-read-and-write-to-use-folios.patch
migrate-use-folio_set_bh-instead-of-set_bh_page.patch
ntfs3-convert-ntfs_get_block_vbo-to-use-a-folio.patch
jbd2-use-a-folio-in-jbd2_journal_write_metadata_buffer.patch
buffer-remove-set_bh_page.patch
zswap-make-zswap_store-take-a-folio.patch
memcg-convert-get_obj_cgroup_from_page-to-get_obj_cgroup_from_folio.patch
swap-remove-some-calls-to-compound_head-in-swap_readpage.patch
zswap-make-zswap_load-take-a-folio.patch
mm-remove-config_per_vma_lock-ifdefs.patch
mm-allow-per-vma-locks-on-file-backed-vmas.patch
mm-move-fault_flag_vma_lock-check-from-handle_mm_fault.patch
mm-handle-pud-faults-under-the-vma-lock.patch
mm-handle-some-pmd-faults-under-the-vma-lock.patch
mm-move-fault_flag_vma_lock-check-down-in-handle_pte_fault.patch
mm-move-fault_flag_vma_lock-check-down-from-do_fault.patch
mm-run-the-fault-around-code-under-the-vma-lock.patch
mm-handle-swap-and-numa-pte-faults-under-the-vma-lock.patch
mm-handle-faults-that-merely-update-the-accessed-bit-under-the-vma-lock.patch
mm-handle-faults-that-merely-update-the-accessed-bit-under-the-vma-lock-fix.patch
