+ mm-allow-fault_dirty_shared_page-to-be-called-under-the-vma-lock.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm: allow fault_dirty_shared_page() to be called under the VMA lock
has been added to the -mm mm-unstable branch.  Its filename is
     mm-allow-fault_dirty_shared_page-to-be-called-under-the-vma-lock.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-allow-fault_dirty_shared_page-to-be-called-under-the-vma-lock.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 (Oracle)" <willy@infradead.org>
Subject: mm: allow fault_dirty_shared_page() to be called under the VMA lock
Date: Sat, 12 Aug 2023 01:20:33 +0100

By making maybe_unlock_mmap_for_io() handle the VMA lock correctly, we
make fault_dirty_shared_page() safe to be called without the mmap lock
held.

Link: https://lkml.kernel.org/r/20230812002033.1002367-1-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reported-by: David Hildenbrand <david@redhat.com>
Tested-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/internal.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/internal.h~mm-allow-fault_dirty_shared_page-to-be-called-under-the-vma-lock
+++ a/mm/internal.h
@@ -706,7 +706,7 @@ static inline struct file *maybe_unlock_
 	if (fault_flag_allow_retry_first(flags) &&
 	    !(flags & FAULT_FLAG_RETRY_NOWAIT)) {
 		fpin = get_file(vmf->vma->vm_file);
-		mmap_read_unlock(vmf->vma->vm_mm);
+		release_fault_lock(vmf);
 	}
 	return fpin;
 }
_

Patches currently in -mm which might be from willy@infradead.org are

mm-memoryc-fix-mismerge.patch
mm-drop-per-vma-lock-when-returning-vm_fault_retry-or-vm_fault_completed-fix.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-improve-the-comment-in-isolate_migratepages_block.patch
minmax-add-in_range-macro.patch
mm-convert-page_table_check_pte_set-to-page_table_check_ptes_set.patch
mm-add-generic-flush_icache_pages-and-documentation.patch
mm-add-folio_flush_mapping.patch
mm-remove-arch_implements_flush_dcache_folio.patch
mm-add-default-definition-of-set_ptes.patch
alpha-implement-the-new-page-table-range-api.patch
arc-implement-the-new-page-table-range-api.patch
arm-implement-the-new-page-table-range-api.patch
arm64-implement-the-new-page-table-range-api.patch
csky-implement-the-new-page-table-range-api.patch
hexagon-implement-the-new-page-table-range-api.patch
ia64-implement-the-new-page-table-range-api.patch
ia64-implement-the-new-page-table-range-api-fix.patch
loongarch-implement-the-new-page-table-range-api.patch
m68k-implement-the-new-page-table-range-api.patch
microblaze-implement-the-new-page-table-range-api.patch
mips-implement-the-new-page-table-range-api.patch
nios2-implement-the-new-page-table-range-api.patch
openrisc-implement-the-new-page-table-range-api.patch
parisc-implement-the-new-page-table-range-api.patch
powerpc-implement-the-new-page-table-range-api.patch
powerpc-implement-the-new-page-table-range-api-fix.patch
riscv-implement-the-new-page-table-range-api.patch
s390-implement-the-new-page-table-range-api.patch
sh-implement-the-new-page-table-range-api.patch
sparc32-implement-the-new-page-table-range-api.patch
sparc64-implement-the-new-page-table-range-api.patch
um-implement-the-new-page-table-range-api.patch
x86-implement-the-new-page-table-range-api.patch
xtensa-implement-the-new-page-table-range-api.patch
mm-remove-page_mapping_file.patch
mm-rationalise-flush_icache_pages-and-flush_icache_page.patch
mm-tidy-up-set_ptes-definition.patch
mm-use-flush_icache_pages-in-do_set_pmd.patch
mm-call-update_mmu_cache_range-in-more-page-fault-handling-paths.patch
mm-allow-fault_dirty_shared_page-to-be-called-under-the-vma-lock.patch