Merge tag 'mm-hotfixes-stable-2026-02-04-15-55' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "Five hotfixes.  Two are cc:stable, two are for MM.

  All are singletons - please see the changelogs for details"

* tag 'mm-hotfixes-stable-2026-02-04-15-55' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  Documentation: document liveupdate cmdline parameter
  mm, shmem: prevent infinite loop on truncate race
  mailmap: update Alexander Mikhalitsyn's emails
  liveupdate: luo_file: do not clear serialized_data on unfreeze
  x86/kfence: fix booting on 32bit non-PAE systems

Author: torvalds

.mailmap

@@ -34,6 +34,7 @@ Alexander Lobakin <[email protected]> <[email protected]>
 Alexander Lobakin <[email protected]> <[email protected]>
 Alexander Mikhalitsyn <[email protected]> <[email protected]>
 Alexander Mikhalitsyn <[email protected]> <[email protected]>
+Alexander Mikhalitsyn <[email protected]> <[email protected]>
 Alexander Sverdlin <[email protected]> <[email protected]>
 Alexander Sverdlin <[email protected]> <[email protected]>
 Alexander Sverdlin <[email protected]> <[email protected]>

Documentation/admin-guide/kernel-parameters.txt

@@ -3472,6 +3472,11 @@ Kernel parameters
 			If there are multiple matching configurations changing
 			the same attribute, the last one is used.
 
+	liveupdate=	[KNL,EARLY]
+			Format: <bool>
+			Enable Live Update Orchestrator (LUO).
+			Default: off.
+
 	load_ramdisk=	[RAM] [Deprecated]
 
 	lockd.nlm_grace_period=P  [NFS] Assign grace period.

arch/x86/include/asm/kfence.h

@@ -42,7 +42,7 @@ static inline bool kfence_protect_page(unsigned long addr, bool protect)
 {
 	unsigned int level;
 	pte_t *pte = lookup_address(addr, &level);
-	pteval_t val;
+	pteval_t val, new;
 
 	if (WARN_ON(!pte || level != PG_LEVEL_4K))
 		return false;
@@ -57,11 +57,12 @@ static inline bool kfence_protect_page(unsigned long addr, bool protect)
 		return true;
 
 	/*
-	 * Otherwise, invert the entire PTE.  This avoids writing out an
+	 * Otherwise, flip the Present bit, taking care to avoid writing an
 	 * L1TF-vulnerable PTE (not present, without the high address bits
 	 * set).
 	 */
-	set_pte(pte, __pte(~val));
+	new = val ^ _PAGE_PRESENT;
+	set_pte(pte, __pte(flip_protnone_guard(val, new, PTE_PFN_MASK)));
 
 	/*
 	 * If the page was protected (non-present) and we're making it

kernel/liveupdate/luo_file.c

@@ -402,8 +402,6 @@ static void luo_file_unfreeze_one(struct luo_file_set *file_set,
 
 		luo_file->fh->ops->unfreeze(&args);
 	}
-
-	luo_file->serialized_data = 0;
 }
 
 static void __luo_file_unfreeze(struct luo_file_set *file_set,

mm/shmem.c

@@ -1211,17 +1211,22 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, uoff_t lend,
 				swaps_freed = shmem_free_swap(mapping, indices[i],
 							      end - 1, folio);
 				if (!swaps_freed) {
-					/*
-					 * If found a large swap entry cross the end border,
-					 * skip it as the truncate_inode_partial_folio above
-					 * should have at least zerod its content once.
-					 */
+					pgoff_t base = indices[i];
+
 					order = shmem_confirm_swap(mapping, indices[i],
 								   radix_to_swp_entry(folio));
-					if (order > 0 && indices[i] + (1 << order) > end)
-						continue;
-					/* Swap was replaced by page: retry */
-					index = indices[i];
+					/*
+					 * If found a large swap entry cross the end or start
+					 * border, skip it as the truncate_inode_partial_folio
+					 * above should have at least zerod its content once.
+					 */
+					if (order > 0) {
+						base = round_down(base, 1 << order);
+						if (base < start || base + (1 << order) > end)
+							continue;
+					}
+					/* Swap was replaced by page or extended, retry */
+					index = base;
 					break;
 				}
 				nr_swaps_freed += swaps_freed;