Merge tag 'mm-hotfixes-stable-2022-06-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull hotfixes from Andrew Morton:
 "Minor things, mainly - mailmap updates, MAINTAINERS updates, etc.

  Fixes for this merge window:

   - fix for a damon boot hang, from SeongJae

   - fix for a kfence warning splat, from Jason Donenfeld

   - fix for zero-pfn pinning, from Alex Williamson

   - fix for fallocate hole punch clearing, from Mike Kravetz

  Fixes for previous releases:

   - fix for a performance regression, from Marcelo

   - fix for a hwpoisining BUG from zhenwei pi"

* tag 'mm-hotfixes-stable-2022-06-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  mailmap: add entry for Christian Marangi
  mm/memory-failure: disable unpoison once hw error happens
  hugetlbfs: zero partial pages during fallocate hole punch
  mm: memcontrol: reference to tools/cgroup/memcg_slabinfo.py
  mm: re-allow pinning of zero pfns
  mm/kfence: select random number before taking raw lock
  MAINTAINERS: add maillist information for LoongArch
  MAINTAINERS: update MM tree references
  MAINTAINERS: update Abel Vesa's email
  MAINTAINERS: add MEMORY HOT(UN)PLUG section and add David as reviewer
  MAINTAINERS: add Miaohe Lin as a memory-failure reviewer
  mailmap: add alias for [email protected]
  mm/damon/reclaim: schedule 'damon_reclaim_timer' only after 'system_wq' is initialized
  kthread: make it clear that kthread_create_on_node() might be terminated by any fatal signal
  mm: lru_cache_disable: use synchronize_rcu_expedited
  mm/page_isolation.c: fix one kernel-doc comment

Author: torvalds

.mailmap

@@ -10,6 +10,8 @@
 # Please keep this list dictionary sorted.
 #
 Aaron Durbin <[email protected]>
+Abel Vesa <[email protected]> <[email protected]>
+Abel Vesa <[email protected]> <[email protected]>
 Abhinav Kumar <[email protected]> <[email protected]>
 Adam Oldham <[email protected]>
 Adam Radford <[email protected]>
@@ -85,6 +87,7 @@ Christian Borntraeger <[email protected]> <[email protected]>
 Christian Brauner <[email protected]> <[email protected]>
 Christian Brauner <[email protected]> <[email protected]>
 Christian Brauner <[email protected]> <[email protected]>
+Christian Marangi <[email protected]>
 Christophe Ricard <[email protected]>
 Christoph Hellwig <[email protected]>
 Colin Ian King <[email protected]> <[email protected]>
@@ -165,6 +168,7 @@ Jan Glauber <[email protected]> <[email protected]>
 Jan Glauber <[email protected]> <[email protected]>
 Jan Glauber <[email protected]> <[email protected]>
 Jarkko Sakkinen <[email protected]> <[email protected]>
+Jarkko Sakkinen <[email protected]> <[email protected]>
 Jason Gunthorpe <[email protected]> <[email protected]>
 Jason Gunthorpe <[email protected]> <[email protected]>
 Jason Gunthorpe <[email protected]> <[email protected]>

Documentation/vm/hwpoison.rst

@@ -120,7 +120,8 @@ Testing
   unpoison-pfn
 	Software-unpoison page at PFN echoed into this file. This way
 	a page can be reused again.  This only works for Linux
-	injected failures, not for real memory failures.
+	injected failures, not for real memory failures. Once any hardware
+	memory failure happens, this feature is disabled.
 
   Note these injection interfaces are not stable and might change between
   kernel versions

MAINTAINERS

@@ -9152,6 +9152,7 @@ F:	drivers/media/platform/st/sti/hva
 
 HWPOISON MEMORY FAILURE HANDLING
 M:	Naoya Horiguchi <[email protected]>
+R:	Miaohe Lin <[email protected]>
 L:	[email protected]
 S:	Maintained
 F:	mm/hwpoison-inject.c
@@ -11623,6 +11624,7 @@ F:	drivers/gpu/drm/bridge/lontium-lt8912b.c
 LOONGARCH
 M:	Huacai Chen <[email protected]>
 R:	WANG Xuerui <[email protected]>
+L:	[email protected]
 S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson.git
 F:	arch/loongarch/
@@ -12879,9 +12881,8 @@ M:	Andrew Morton <[email protected]>
 L:	[email protected]
 S:	Maintained
 W:	http://www.linux-mm.org
-T:	quilt https://ozlabs.org/~akpm/mmotm/
-T:	quilt https://ozlabs.org/~akpm/mmots/
-T:	git git://github.com/hnaz/linux-mm.git
+T:	git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
+T:	quilt git://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new
 F:	include/linux/gfp.h
 F:	include/linux/memory_hotplug.h
 F:	include/linux/mm.h
@@ -12891,6 +12892,18 @@ F:	include/linux/vmalloc.h
 F:	mm/
 F:	tools/testing/selftests/vm/
 
+MEMORY HOT(UN)PLUG
+M:	David Hildenbrand <[email protected]>
+M:	Oscar Salvador <[email protected]>
+L:	[email protected]
+S:	Maintained
+F:	Documentation/admin-guide/mm/memory-hotplug.rst
+F:	Documentation/core-api/memory-hotplug.rst
+F:	drivers/base/memory.c
+F:	include/linux/memory_hotplug.h
+F:	mm/memory_hotplug.c
+F:	tools/testing/selftests/memory-hotplug/
+
 MEMORY TECHNOLOGY DEVICES (MTD)
 M:	Miquel Raynal <[email protected]>
 M:	Richard Weinberger <[email protected]>
@@ -14295,7 +14308,7 @@ F:	drivers/iio/gyro/fxas21002c_i2c.c
 F:	drivers/iio/gyro/fxas21002c_spi.c
 
 NXP i.MX CLOCK DRIVERS
-M:	Abel Vesa <[email protected]>
+M:	Abel Vesa <[email protected]>
 L:	[email protected]
 L:	[email protected]
 S:	Maintained

drivers/base/memory.c

@@ -558,7 +558,7 @@ static ssize_t hard_offline_page_store(struct device *dev,
 	if (kstrtoull(buf, 0, &pfn) < 0)
 		return -EINVAL;
 	pfn >>= PAGE_SHIFT;
-	ret = memory_failure(pfn, 0);
+	ret = memory_failure(pfn, MF_SW_SIMULATED);
 	if (ret == -EOPNOTSUPP)
 		ret = 0;
 	return ret ? ret : count;

fs/hugetlbfs/inode.c

@@ -600,41 +600,79 @@ static void hugetlb_vmtruncate(struct inode *inode, loff_t offset)
 	remove_inode_hugepages(inode, offset, LLONG_MAX);
 }
 
+static void hugetlbfs_zero_partial_page(struct hstate *h,
+					struct address_space *mapping,
+					loff_t start,
+					loff_t end)
+{
+	pgoff_t idx = start >> huge_page_shift(h);
+	struct folio *folio;
+
+	folio = filemap_lock_folio(mapping, idx);
+	if (!folio)
+		return;
+
+	start = start & ~huge_page_mask(h);
+	end = end & ~huge_page_mask(h);
+	if (!end)
+		end = huge_page_size(h);
+
+	folio_zero_segment(folio, (size_t)start, (size_t)end);
+
+	folio_unlock(folio);
+	folio_put(folio);
+}
+
 static long hugetlbfs_punch_hole(struct inode *inode, loff_t offset, loff_t len)
 {
+	struct hugetlbfs_inode_info *info = HUGETLBFS_I(inode);
+	struct address_space *mapping = inode->i_mapping;
 	struct hstate *h = hstate_inode(inode);
 	loff_t hpage_size = huge_page_size(h);
 	loff_t hole_start, hole_end;
 
 	/*
-	 * For hole punch round up the beginning offset of the hole and
-	 * round down the end.
+	 * hole_start and hole_end indicate the full pages within the hole.
 	 */
 	hole_start = round_up(offset, hpage_size);
 	hole_end = round_down(offset + len, hpage_size);
 
-	if (hole_end > hole_start) {
-		struct address_space *mapping = inode->i_mapping;
-		struct hugetlbfs_inode_info *info = HUGETLBFS_I(inode);
+	inode_lock(inode);
 
-		inode_lock(inode);
+	/* protected by i_rwsem */
+	if (info->seals & (F_SEAL_WRITE | F_SEAL_FUTURE_WRITE)) {
+		inode_unlock(inode);
+		return -EPERM;
+	}
 
-		/* protected by i_rwsem */
-		if (info->seals & (F_SEAL_WRITE | F_SEAL_FUTURE_WRITE)) {
-			inode_unlock(inode);
-			return -EPERM;
-		}
+	i_mmap_lock_write(mapping);
+
+	/* If range starts before first full page, zero partial page. */
+	if (offset < hole_start)
+		hugetlbfs_zero_partial_page(h, mapping,
+				offset, min(offset + len, hole_start));
 
-		i_mmap_lock_write(mapping);
+	/* Unmap users of full pages in the hole. */
+	if (hole_end > hole_start) {
 		if (!RB_EMPTY_ROOT(&mapping->i_mmap.rb_root))
 			hugetlb_vmdelete_list(&mapping->i_mmap,
 					      hole_start >> PAGE_SHIFT,
 					      hole_end >> PAGE_SHIFT, 0);
-		i_mmap_unlock_write(mapping);
-		remove_inode_hugepages(inode, hole_start, hole_end);
-		inode_unlock(inode);
 	}
 
+	/* If range extends beyond last full page, zero partial page. */
+	if ((offset + len) > hole_end && (offset + len) > hole_start)
+		hugetlbfs_zero_partial_page(h, mapping,
+				hole_end, offset + len);
+
+	i_mmap_unlock_write(mapping);
+
+	/* Remove full pages from the file. */
+	if (hole_end > hole_start)
+		remove_inode_hugepages(inode, hole_start, hole_end);
+
+	inode_unlock(inode);
+
 	return 0;
 }
 

include/linux/mm.h

@@ -1600,7 +1600,7 @@ static inline bool is_pinnable_page(struct page *page)
 	if (mt == MIGRATE_CMA || mt == MIGRATE_ISOLATE)
 		return false;
 #endif
-	return !(is_zone_movable_page(page) || is_zero_pfn(page_to_pfn(page)));
+	return !is_zone_movable_page(page) || is_zero_pfn(page_to_pfn(page));
 }
 #else
 static inline bool is_pinnable_page(struct page *page)
@@ -3232,6 +3232,7 @@ enum mf_flags {
 	MF_MUST_KILL = 1 << 2,
 	MF_SOFT_OFFLINE = 1 << 3,
 	MF_UNPOISON = 1 << 4,
+	MF_SW_SIMULATED = 1 << 5,
 };
 extern int memory_failure(unsigned long pfn, int flags);
 extern void memory_failure_queue(unsigned long pfn, int flags);

kernel/kthread.c

@@ -340,7 +340,7 @@ static int kthread(void *_create)
 
 	self = to_kthread(current);
 
-	/* If user was SIGKILLed, I release the structure. */
+	/* Release the structure when caller killed by a fatal signal. */
 	done = xchg(&create->done, NULL);
 	if (!done) {
 		kfree(create);
@@ -398,7 +398,7 @@ static void create_kthread(struct kthread_create_info *create)
 	/* We want our own signal handler (we take no signals by default). */
 	pid = kernel_thread(kthread, create, CLONE_FS | CLONE_FILES | SIGCHLD);
 	if (pid < 0) {
-		/* If user was SIGKILLed, I release the structure. */
+		/* Release the structure when caller killed by a fatal signal. */
 		struct completion *done = xchg(&create->done, NULL);
 
 		if (!done) {
@@ -440,9 +440,9 @@ struct task_struct *__kthread_create_on_node(int (*threadfn)(void *data),
 	 */
 	if (unlikely(wait_for_completion_killable(&done))) {
 		/*
-		 * If I was SIGKILLed before kthreadd (or new kernel thread)
-		 * calls complete(), leave the cleanup of this structure to
-		 * that thread.
+		 * If I was killed by a fatal signal before kthreadd (or new
+		 * kernel thread) calls complete(), leave the cleanup of this
+		 * structure to that thread.
 		 */
 		if (xchg(&create->done, NULL))
 			return ERR_PTR(-EINTR);
@@ -876,7 +876,7 @@ __kthread_create_worker(int cpu, unsigned int flags,
  *
  * Returns a pointer to the allocated worker on success, ERR_PTR(-ENOMEM)
  * when the needed structures could not get allocated, and ERR_PTR(-EINTR)
- * when the worker was SIGKILLed.
+ * when the caller was killed by a fatal signal.
  */
 struct kthread_worker *
 kthread_create_worker(unsigned int flags, const char namefmt[], ...)
@@ -925,7 +925,7 @@ EXPORT_SYMBOL(kthread_create_worker);
  * Return:
  * The pointer to the allocated worker on success, ERR_PTR(-ENOMEM)
  * when the needed structures could not get allocated, and ERR_PTR(-EINTR)
- * when the worker was SIGKILLed.
+ * when the caller was killed by a fatal signal.
  */
 struct kthread_worker *
 kthread_create_worker_on_cpu(int cpu, unsigned int flags,

mm/damon/reclaim.c

@@ -374,6 +374,8 @@ static void damon_reclaim_timer_fn(struct work_struct *work)
 }
 static DECLARE_DELAYED_WORK(damon_reclaim_timer, damon_reclaim_timer_fn);
 
+static bool damon_reclaim_initialized;
+
 static int enabled_store(const char *val,
 		const struct kernel_param *kp)
 {
@@ -382,6 +384,10 @@ static int enabled_store(const char *val,
 	if (rc < 0)
 		return rc;
 
+	/* system_wq might not initialized yet */
+	if (!damon_reclaim_initialized)
+		return rc;
+
 	if (enabled)
 		schedule_delayed_work(&damon_reclaim_timer, 0);
 
@@ -449,6 +455,8 @@ static int __init damon_reclaim_init(void)
 	damon_add_target(ctx, target);
 
 	schedule_delayed_work(&damon_reclaim_timer, 0);
+
+	damon_reclaim_initialized = true;
 	return 0;
 }
 

mm/hwpoison-inject.c

@@ -48,7 +48,7 @@ static int hwpoison_inject(void *data, u64 val)
 
 inject:
 	pr_info("Injecting memory failure at pfn %#lx\n", pfn);
-	err = memory_failure(pfn, 0);
+	err = memory_failure(pfn, MF_SW_SIMULATED);
 	return (err == -EOPNOTSUPP) ? 0 : err;
 }
 

mm/kfence/core.c

@@ -360,6 +360,9 @@ static void *kfence_guarded_alloc(struct kmem_cache *cache, size_t size, gfp_t g
 	unsigned long flags;
 	struct slab *slab;
 	void *addr;
+	const bool random_right_allocate = prandom_u32_max(2);
+	const bool random_fault = CONFIG_KFENCE_STRESS_TEST_FAULTS &&
+				  !prandom_u32_max(CONFIG_KFENCE_STRESS_TEST_FAULTS);
 
 	/* Try to obtain a free object. */
 	raw_spin_lock_irqsave(&kfence_freelist_lock, flags);
@@ -404,7 +407,7 @@ static void *kfence_guarded_alloc(struct kmem_cache *cache, size_t size, gfp_t g
 	 * is that the out-of-bounds accesses detected are deterministic for
 	 * such allocations.
 	 */
-	if (prandom_u32_max(2)) {
+	if (random_right_allocate) {
 		/* Allocate on the "right" side, re-calculate address. */
 		meta->addr += PAGE_SIZE - size;
 		meta->addr = ALIGN_DOWN(meta->addr, cache->align);
@@ -444,7 +447,7 @@ static void *kfence_guarded_alloc(struct kmem_cache *cache, size_t size, gfp_t g
 	if (cache->ctor)
 		cache->ctor(addr);
 
-	if (CONFIG_KFENCE_STRESS_TEST_FAULTS && !prandom_u32_max(CONFIG_KFENCE_STRESS_TEST_FAULTS))
+	if (random_fault)
 		kfence_protect(meta->addr); /* Random "faults" by protecting the object. */
 
 	atomic_long_inc(&counters[KFENCE_COUNTER_ALLOCATED]);