+ mm-smaps-dont-access-young-dirty-bit-if-pte-unpresent.patch added to mm-hotfixes-unstable branch

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

The patch titled
     Subject: mm/smaps: don't access young/dirty bit if pte unpresent
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     mm-smaps-dont-access-young-dirty-bit-if-pte-unpresent.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-smaps-dont-access-young-dirty-bit-if-pte-unpresent.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Peter Xu <peterx@redhat.com>
Subject: mm/smaps: don't access young/dirty bit if pte unpresent
Date: Wed, 3 Aug 2022 18:03:29 -0400

These bits should only be valid when the ptes are present.  Introduce two
booleans for it and set it to false when !pte_present().

Link: https://lkml.kernel.org/r/20220803220329.46299-1-peterx@redhat.com
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Fixes: b1d4d9e0cbd0 ("proc/smaps: carefully handle migration entries", 2012-05-31)
Signed-off-by: Peter Xu <peterx@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/proc/task_mmu.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

--- a/fs/proc/task_mmu.c~mm-smaps-dont-access-young-dirty-bit-if-pte-unpresent
+++ a/fs/proc/task_mmu.c
@@ -525,10 +525,12 @@ static void smaps_pte_entry(pte_t *pte,
 	struct vm_area_struct *vma = walk->vma;
 	bool locked = !!(vma->vm_flags & VM_LOCKED);
 	struct page *page = NULL;
-	bool migration = false;
+	bool migration = false, young = false, dirty = false;
 
 	if (pte_present(*pte)) {
 		page = vm_normal_page(vma, addr, *pte);
+		young = pte_young(*pte);
+		dirty = pte_dirty(*pte);
 	} else if (is_swap_pte(*pte)) {
 		swp_entry_t swpent = pte_to_swp_entry(*pte);
 
@@ -558,8 +560,7 @@ static void smaps_pte_entry(pte_t *pte,
 	if (!page)
 		return;
 
-	smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte),
-		      locked, migration);
+	smaps_account(mss, page, false, young, dirty, locked, migration);
 }
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
_

Patches currently in -mm which might be from peterx@redhat.com are

mm-smaps-dont-access-young-dirty-bit-if-pte-unpresent.patch