Merge tag 'mm-nonmm-stable-2025-05-31-15-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

 - "hung_task: extend blocking task stacktrace dump to semaphore" from
   Lance Yang enhances the hung task detector.

   The detector presently dumps the blocking tasks's stack when it is
   blocked on a mutex. Lance's series extends this to semaphores

 - "nilfs2: improve sanity checks in dirty state propagation" from
   Wentao Liang addresses a couple of minor flaws in nilfs2

 - "scripts/gdb: Fixes related to lx_per_cpu()" from Illia Ostapyshyn
   fixes a couple of issues in the gdb scripts

 - "Support kdump with LUKS encryption by reusing LUKS volume keys" from
   Coiby Xu addresses a usability problem with kdump.

   When the dump device is LUKS-encrypted, the kdump kernel may not have
   the keys to the encrypted filesystem. A full writeup of this is in
   the series [0/N] cover letter

 - "sysfs: add counters for lockups and stalls" from Max Kellermann adds
   /sys/kernel/hardlockup_count and /sys/kernel/hardlockup_count and
   /sys/kernel/rcu_stall_count

 - "fork: Page operation cleanups in the fork code" from Pasha Tatashin
   implements a number of code cleanups in fork.c

 - "scripts/gdb/symbols: determine KASLR offset on s390 during early
   boot" from Ilya Leoshkevich fixes some s390 issues in the gdb
   scripts

* tag 'mm-nonmm-stable-2025-05-31-15-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (67 commits)
  llist: make llist_add_batch() a static inline
  delayacct: remove redundant code and adjust indentation
  squashfs: add optional full compressed block caching
  crash_dump, nvme: select CONFIGFS_FS as built-in
  scripts/gdb/symbols: determine KASLR offset on s390 during early boot
  scripts/gdb/symbols: factor out pagination_off()
  scripts/gdb/symbols: factor out get_vmlinux()
  kernel/panic.c: format kernel-doc comments
  mailmap: update and consolidate Casey Connolly's name and email
  nilfs2: remove wbc->for_reclaim handling
  fork: define a local GFP_VMAP_STACK
  fork: check charging success before zeroing stack
  fork: clean-up naming of vm_stack/vm_struct variables in vmap stacks code
  fork: clean-up ifdef logic around stack allocation
  kernel/rcu/tree_stall: add /sys/kernel/rcu_stall_count
  kernel/watchdog: add /sys/kernel/{hard,soft}lockup_count
  x86/crash: make the page that stores the dm crypt keys inaccessible
  x86/crash: pass dm crypt keys to kdump kernel
  Revert "x86/mm: Remove unused __set_memory_prot()"
  crash_dump: retrieve dm crypt keys in kdump kernel
  ...

1 files changed, 32 insertions, 36 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index 38645039dd8f..bd743900354c 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -421,44 +421,30 @@ kill_orphaned_pgrp(struct task_struct *tsk, struct task_struct *parent)
 	}
 }
 
-static void coredump_task_exit(struct task_struct *tsk)
+static void coredump_task_exit(struct task_struct *tsk,
+			       struct core_state *core_state)
 {
-	struct core_state *core_state;
+	struct core_thread self;
 
+	self.task = tsk;
+	if (self.task->flags & PF_SIGNALED)
+		self.next = xchg(&core_state->dumper.next, &self);
+	else
+		self.task = NULL;
 	/*
-	 * Serialize with any possible pending coredump.
-	 * We must hold siglock around checking core_state
-	 * and setting PF_POSTCOREDUMP.  The core-inducing thread
-	 * will increment ->nr_threads for each thread in the
-	 * group without PF_POSTCOREDUMP set.
+	 * Implies mb(), the result of xchg() must be visible
+	 * to core_state->dumper.
 	 */
-	spin_lock_irq(&tsk->sighand->siglock);
-	tsk->flags |= PF_POSTCOREDUMP;
-	core_state = tsk->signal->core_state;
-	spin_unlock_irq(&tsk->sighand->siglock);
-	if (core_state) {
-		struct core_thread self;
-
-		self.task = current;
-		if (self.task->flags & PF_SIGNALED)
-			self.next = xchg(&core_state->dumper.next, &self);
-		else
-			self.task = NULL;
-		/*
-		 * Implies mb(), the result of xchg() must be visible
-		 * to core_state->dumper.
-		 */
-		if (atomic_dec_and_test(&core_state->nr_threads))
-			complete(&core_state->startup);
+	if (atomic_dec_and_test(&core_state->nr_threads))
+		complete(&core_state->startup);
 
-		for (;;) {
-			set_current_state(TASK_IDLE|TASK_FREEZABLE);
-			if (!self.task) /* see coredump_finish() */
-				break;
-			schedule();
-		}
-		__set_current_state(TASK_RUNNING);
+	for (;;) {
+		set_current_state(TASK_IDLE|TASK_FREEZABLE);
+		if (!self.task) /* see coredump_finish() */
+			break;
+		schedule();
 	}
+	__set_current_state(TASK_RUNNING);
 }
 
 #ifdef CONFIG_MEMCG
@@ -882,6 +868,7 @@ static void synchronize_group_exit(struct task_struct *tsk, long code)
 {
 	struct sighand_struct *sighand = tsk->sighand;
 	struct signal_struct *signal = tsk->signal;
+	struct core_state *core_state;
 
 	spin_lock_irq(&sighand->siglock);
 	signal->quick_threads--;
@@ -891,7 +878,19 @@ static void synchronize_group_exit(struct task_struct *tsk, long code)
 		signal->group_exit_code = code;
 		signal->group_stop_count = 0;
 	}
+	/*
+	 * Serialize with any possible pending coredump.
+	 * We must hold siglock around checking core_state
+	 * and setting PF_POSTCOREDUMP.  The core-inducing thread
+	 * will increment ->nr_threads for each thread in the
+	 * group without PF_POSTCOREDUMP set.
+	 */
+	tsk->flags |= PF_POSTCOREDUMP;
+	core_state = signal->core_state;
 	spin_unlock_irq(&sighand->siglock);
+
+	if (unlikely(core_state))
+		coredump_task_exit(tsk, core_state);
 }
 
 void __noreturn do_exit(long code)
@@ -900,15 +899,12 @@ void __noreturn do_exit(long code)
 	int group_dead;
 
 	WARN_ON(irqs_disabled());
-
-	synchronize_group_exit(tsk, code);
-
 	WARN_ON(tsk->plug);
 
 	kcov_task_exit(tsk);
 	kmsan_task_exit(tsk);
 
-	coredump_task_exit(tsk);
+	synchronize_group_exit(tsk, code);
 	ptrace_event(PTRACE_EVENT_EXIT, code);
 	user_events_exit(tsk);