The quilt patch titled
Subject: mm: handle COW faults under the VMA lock
has been removed from the -mm tree. Its filename was
mm-handle-cow-faults-under-the-vma-lock.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: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm: handle COW faults under the VMA lock
Date: Fri, 6 Oct 2023 20:53:16 +0100
If the page is not currently present in the page tables, we need to call
the page fault handler to find out which page we're supposed to COW, so we
need to both check that there is already an anon_vma and that the fault
handler doesn't need the mmap_lock.
Link: https://lkml.kernel.org/r/20231006195318.4087158-5-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memory.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)
--- a/mm/memory.c~mm-handle-cow-faults-under-the-vma-lock
+++ a/mm/memory.c
@@ -4639,13 +4639,11 @@ static vm_fault_t do_cow_fault(struct vm
struct vm_area_struct *vma = vmf->vma;
vm_fault_t ret;
- if (vmf->flags & FAULT_FLAG_VMA_LOCK) {
- vma_end_read(vma);
- return VM_FAULT_RETRY;
- }
-
- if (unlikely(anon_vma_prepare(vma)))
- return VM_FAULT_OOM;
+ ret = vmf_can_call_fault(vmf);
+ if (!ret)
+ ret = vmf_anon_prepare(vmf);
+ if (ret)
+ return ret;
vmf->cow_page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, vmf->address);
if (!vmf->cow_page)
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
buffer-make-folio_create_empty_buffers-return-a-buffer_head.patch
mpage-convert-map_buffer_to_folio-to-folio_create_empty_buffers.patch
ext4-convert-to-folio_create_empty_buffers.patch
buffer-add-get_nth_bh.patch
gfs2-convert-inode-unstuffing-to-use-a-folio.patch
gfs2-convert-gfs2_getbuf-to-folios.patch
gfs2-convert-gfs2_getjdatabuf-to-use-a-folio.patch
gfs2-convert-gfs2_write_buf_to_page-to-use-a-folio.patch
nilfs2-convert-nilfs_mdt_freeze_buffer-to-use-a-folio.patch
nilfs2-convert-nilfs_grab_buffer-to-use-a-folio.patch
nilfs2-convert-nilfs_copy_page-to-nilfs_copy_folio.patch
nilfs2-convert-nilfs_mdt_forget_block-to-use-a-folio.patch
nilfs2-convert-nilfs_mdt_get_frozen_buffer-to-use-a-folio.patch
nilfs2-remove-nilfs_page_get_nth_block.patch
nilfs2-convert-nilfs_lookup_dirty_data_buffers-to-use-folio_create_empty_buffers.patch
ntfs-convert-ntfs_read_block-to-use-a-folio.patch
ntfs-convert-ntfs_writepage-to-use-a-folio.patch
ntfs-convert-ntfs_prepare_pages_for_non_resident_write-to-folios.patch
ntfs3-convert-ntfs_zero_range-to-use-a-folio.patch
ocfs2-convert-ocfs2_map_page_blocks-to-use-a-folio.patch
reiserfs-convert-writepage-to-use-a-folio.patch
ufs-add-ufs_get_locked_folio-and-ufs_put_locked_folio.patch
ufs-use-ufs_get_locked_folio-in-ufs_alloc_lastblock.patch
ufs-convert-ufs_change_blocknr-to-use-folios.patch
ufs-remove-ufs_get_locked_page.patch
buffer-remove-folio_create_empty_buffers.patch
