Merge tag 'mm-hotfixes-stable-2025-01-13-00-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "18 hotfixes. 11 are cc:stable. 13 are MM and 5 are non-MM.

  All patches are singletons - please see the relevant changelogs for
  details"

* tag 'mm-hotfixes-stable-2025-01-13-00-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  fs/proc: fix softlockup in __read_vmcore (part 2)
  mm: fix assertion in folio_end_read()
  mm: vmscan : pgdemote vmstat is not getting updated when MGLRU is enabled.
  vmstat: disable vmstat_work on vmstat_cpu_down_prep()
  zram: fix potential UAF of zram table
  selftests/mm: set allocated memory to non-zero content in cow test
  mm: clear uffd-wp PTE/PMD state on mremap()
  module: fix writing of livepatch relocations in ROX text
  mm: zswap: properly synchronize freeing resources during CPU hotunplug
  Revert "mm: zswap: fix race between [de]compression and CPU hotunplug"
  hugetlb: fix NULL pointer dereference in trace_hugetlbfs_alloc_inode
  mm: fix div by zero in bdi_ratio_from_pages
  x86/execmem: fix ROX cache usage in Xen PV guests
  filemap: avoid truncating 64-bit offset to 32 bits
  tools: fix atomic_set() definition to set the value correctly
  mm/mempolicy: count MPOL_WEIGHTED_INTERLEAVE to "interleave_hit"
  scripts/decode_stacktrace.sh: fix decoding of lines with an additional info
  mm/kmemleak: fix percpu memory leak detection failure

1 files changed, 13 insertions, 2 deletions

diff --git a/mm/vmstat.c b/mm/vmstat.c
index 4d016314a56c..16bfe1c694dd 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -2122,10 +2122,20 @@ static void __init start_shepherd_timer(void)
 {
 	int cpu;
 
-	for_each_possible_cpu(cpu)
+	for_each_possible_cpu(cpu) {
 		INIT_DEFERRABLE_WORK(per_cpu_ptr(&vmstat_work, cpu),
 			vmstat_update);
 
+		/*
+		 * For secondary CPUs during CPU hotplug scenarios,
+		 * vmstat_cpu_online() will enable the work.
+		 * mm/vmstat:online enables and disables vmstat_work
+		 * symmetrically during CPU hotplug events.
+		 */
+		if (!cpu_online(cpu))
+			disable_delayed_work_sync(&per_cpu(vmstat_work, cpu));
+	}
+
 	schedule_delayed_work(&shepherd,
 		round_jiffies_relative(sysctl_stat_interval));
 }
@@ -2148,13 +2158,14 @@ static int vmstat_cpu_online(unsigned int cpu)
 	if (!node_state(cpu_to_node(cpu), N_CPU)) {
 		node_set_state(cpu_to_node(cpu), N_CPU);
 	}
+	enable_delayed_work(&per_cpu(vmstat_work, cpu));
 
 	return 0;
 }
 
 static int vmstat_cpu_down_prep(unsigned int cpu)
 {
-	cancel_delayed_work_sync(&per_cpu(vmstat_work, cpu));
+	disable_delayed_work_sync(&per_cpu(vmstat_work, cpu));
 	return 0;
 }