+ mm-memory-dont-require-head-page-for-do_set_pmd.patch added to mm-unstable branch

+ mm-memory-dont-require-head-page-for-do_set_pmd.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/memory: don't require head page for do_set_pmd()
has been added to the -mm mm-unstable branch.  Its filename is
     mm-memory-dont-require-head-page-for-do_set_pmd.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memory-dont-require-head-page-for-do_set_pmd.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: Andrew Bresticker <abrestic@rivosinc.com>
Subject: mm/memory: don't require head page for do_set_pmd()
Date: Tue, 11 Jun 2024 08:32:16 -0700

The requirement that the head page be passed to do_set_pmd() was added in
commit ef37b2ea08ac ("mm/memory: page_add_file_rmap() ->
folio_add_file_rmap_[pte|pmd]()") and prevents pmd-mapping in the
finish_fault() and filemap_map_pages() paths if the page to be inserted is
anything but the head page for an otherwise suitable vma and pmd-sized
page.

Link: https://lkml.kernel.org/r/20240611153216.2794513-1-abrestic@rivosinc.com
Fixes: ef37b2ea08ac ("mm/memory: page_add_file_rmap() -> folio_add_file_rmap_[pte|pmd]()")
Signed-off-by: Andrew Bresticker <abrestic@rivosinc.com>
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memory.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/mm/memory.c~mm-memory-dont-require-head-page-for-do_set_pmd
+++ a/mm/memory.c
@@ -4699,8 +4699,9 @@ vm_fault_t do_set_pmd(struct vm_fault *v
 	if (!thp_vma_suitable_order(vma, haddr, PMD_ORDER))
 		return ret;
 
-	if (page != &folio->page || folio_order(folio) != HPAGE_PMD_ORDER)
+	if (folio_order(folio) != HPAGE_PMD_ORDER)
 		return ret;
+	page = &folio->page;
 
 	/*
 	 * Just backoff if any subpage of a THP is corrupted otherwise
_

Patches currently in -mm which might be from abrestic@rivosinc.com are

mm-memory-dont-require-head-page-for-do_set_pmd.patch