+ mm-update-the-memmap-stat-before-page-is-freed.patch added to mm-hotfixes-unstable branch

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

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The patch titled
     Subject: mm: update the memmap stat before page is freed
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     mm-update-the-memmap-stat-before-page-is-freed.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-update-the-memmap-stat-before-page-is-freed.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: Pasha Tatashin <pasha.tatashin@soleen.com>
Subject: mm: update the memmap stat before page is freed
Date: Tue, 6 Aug 2024 22:14:53 +0000

It is more logical to update the stat before the page is freed, to avoid
use after free scenarios.

Link: https://lkml.kernel.org/r/20240806221454.1971755-1-pasha.tatashin@soleen.com
Fixes: 15995a352474 ("mm: report per-page metadata information")
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Björn Töpel <bjorn@rivosinc.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chen Jiahao <chenjiahao16@huawei.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dawei Li <dawei.li@shingroup.cn>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nam Cao <namcao@linutronix.de>
Cc: Naveen N Rao <naveen@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Philippe Mathieu-Daudé <philmd@linaro.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Sourav Panda <souravpanda@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Cc: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/hugetlb_vmemmap.c |    4 ++--
 mm/page_ext.c        |    8 ++++----
 2 files changed, 6 insertions(+), 6 deletions(-)

--- a/mm/hugetlb_vmemmap.c~mm-update-the-memmap-stat-before-page-is-freed
+++ a/mm/hugetlb_vmemmap.c
@@ -185,11 +185,11 @@ static int vmemmap_remap_range(unsigned
 static inline void free_vmemmap_page(struct page *page)
 {
 	if (PageReserved(page)) {
-		free_bootmem_page(page);
 		mod_node_page_state(page_pgdat(page), NR_MEMMAP_BOOT, -1);
+		free_bootmem_page(page);
 	} else {
-		__free_page(page);
 		mod_node_page_state(page_pgdat(page), NR_MEMMAP, -1);
+		__free_page(page);
 	}
 }
 
--- a/mm/page_ext.c~mm-update-the-memmap-stat-before-page-is-freed
+++ a/mm/page_ext.c
@@ -330,18 +330,18 @@ static void free_page_ext(void *addr)
 	if (is_vmalloc_addr(addr)) {
 		page = vmalloc_to_page(addr);
 		pgdat = page_pgdat(page);
+		mod_node_page_state(pgdat, NR_MEMMAP,
+				    -1L * (DIV_ROUND_UP(table_size, PAGE_SIZE)));
 		vfree(addr);
 	} else {
 		page = virt_to_page(addr);
 		pgdat = page_pgdat(page);
+		mod_node_page_state(pgdat, NR_MEMMAP,
+				    -1L * (DIV_ROUND_UP(table_size, PAGE_SIZE)));
 		BUG_ON(PageReserved(page));
 		kmemleak_free(addr);
 		free_pages_exact(addr, table_size);
 	}
-
-	mod_node_page_state(pgdat, NR_MEMMAP,
-			    -1L * (DIV_ROUND_UP(table_size, PAGE_SIZE)));
-
 }
 
 static void __free_page_ext(unsigned long pfn)
_

Patches currently in -mm which might be from pasha.tatashin@soleen.com are

mm-update-the-memmap-stat-before-page-is-freed.patch
mm-keep-nid-around-during-hot-remove.patch
memcg-increase-the-valid-index-range-for-memcg-stats-v5.patch
vmstat-kernel-stack-usage-histogram.patch
task_stack-uninline-stack_not_used.patch