31 hotfixes. 9 are cc:stable and the remainder address post-6.15 issues

or aren't considered necessary for -stable kernels.
 
 22 patches are for MM, 9 are otherwise.
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Merge tag 'mm-hotfixes-stable-2025-04-16-19-59' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc hotfixes from Andrew Morton:
 "31 hotfixes.

  9 are cc:stable and the remainder address post-6.15 issues or aren't
  considered necessary for -stable kernels.

  22 patches are for MM, 9 are otherwise"

* tag 'mm-hotfixes-stable-2025-04-16-19-59' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (31 commits)
  MAINTAINERS: update HUGETLB reviewers
  mm: fix apply_to_existing_page_range()
  selftests/mm: fix compiler -Wmaybe-uninitialized warning
  alloc_tag: handle incomplete bulk allocations in vm_module_tags_populate
  mailmap: add entry for Jean-Michel Hautbois
  mm: (un)track_pfn_copy() fix + doc improvements
  mm: fix filemap_get_folios_contig returning batches of identical folios
  mm/hugetlb: add a line break at the end of the format string
  selftests: mincore: fix tmpfs mincore test failure
  mm/hugetlb: fix set_max_huge_pages() when there are surplus pages
  mm/cma: report base address of single range correctly
  mm: page_alloc: speed up fallbacks in rmqueue_bulk()
  kunit: slub: add module description
  mm/kasan: add module decription
  ucs2_string: add module description
  zlib: add module description
  fpga: tests: add module descriptions
  samples/livepatch: add module descriptions
  ASN.1: add module description
  mm/vma: add give_up_on_oom option on modify/merge, use in uffd release
  ...

.mailmap

@@ -322,6 +322,7 @@ Jayachandran C <c.jayachandran@gmail.com> <jchandra@broadcom.com>
 Jayachandran C <c.jayachandran@gmail.com> <jchandra@digeo.com>
 Jayachandran C <c.jayachandran@gmail.com> <jnair@caviumnetworks.com>
 <jean-philippe@linaro.org> <jean-philippe.brucker@arm.com>
+Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org> <jeanmichel.hautbois@ideasonboard.com>
 Jean Tourrilhes <jt@hpl.hp.com>
 Jeevan Shriram <quic_jshriram@quicinc.com> <jshriram@codeaurora.org>
 Jeff Garzik <jgarzik@pretzel.yyz.us>
@@ -438,6 +439,8 @@ Linus Lüssing <linus.luessing@c0d3.blue> <ll@simonwunderlich.de>
 Li Yang <leoyang.li@nxp.com> <leoli@freescale.com>
 Li Yang <leoyang.li@nxp.com> <leo@zh-kernel.org>
 Lior David <quic_liord@quicinc.com> <liord@codeaurora.org>
+Loic Poulain <loic.poulain@oss.qualcomm.com> <loic.poulain@linaro.org>
+Loic Poulain <loic.poulain@oss.qualcomm.com> <loic.poulain@intel.com>
 Lorenzo Pieralisi <lpieralisi@kernel.org> <lorenzo.pieralisi@arm.com>
 Lorenzo Stoakes <lorenzo.stoakes@oracle.com> <lstoakes@gmail.com>
 Luca Ceresoli <luca.ceresoli@bootlin.com> <luca@lucaceresoli.net>

Documentation/userspace-api/mseal.rst

@@ -27,7 +27,7 @@ SYSCALL
 =======
 mseal syscall signature
 -----------------------
-   ``int mseal(void \* addr, size_t len, unsigned long flags)``
+   ``int mseal(void *addr, size_t len, unsigned long flags)``
 
    **addr**/**len**: virtual memory address range.
       The address range set by **addr**/**len** must meet:

MAINTAINERS

@@ -10956,6 +10956,7 @@ F:	include/linux/platform_data/huawei-gaokun-ec.h
 
 HUGETLB SUBSYSTEM
 M:	Muchun Song <muchun.song@linux.dev>
+R:	Oscar Salvador <osalvador@suse.de>
 L:	linux-mm@kvack.org
 S:	Maintained
 F:	Documentation/ABI/testing/sysfs-kernel-mm-hugepages
@@ -12812,6 +12813,7 @@ F:	lib/Kconfig.kcsan
 F:	scripts/Makefile.kcsan
 
 KDUMP
+M:	Andrew Morton <akpm@linux-foundation.org>
 M:	Baoquan He <bhe@redhat.com>
 R:	Vivek Goyal <vgoyal@redhat.com>
 R:	Dave Young <dyoung@redhat.com>
@@ -13113,6 +13115,8 @@ F:	fs/kernfs/
 F:	include/linux/kernfs.h
 
 KEXEC
+M:	Andrew Morton <akpm@linux-foundation.org>
+M:	Baoquan He <bhe@redhat.com>
 L:	kexec@lists.infradead.org
 W:	http://kernel.org/pub/linux/utils/kernel/kexec/
 F:	include/linux/kexec.h

drivers/fpga/tests/fpga-bridge-test.c

@@ -170,4 +170,5 @@ static struct kunit_suite fpga_bridge_suite = {
 
 kunit_test_suite(fpga_bridge_suite);
 
+MODULE_DESCRIPTION("KUnit test for the FPGA Bridge");
 MODULE_LICENSE("GPL");

drivers/fpga/tests/fpga-mgr-test.c

@@ -330,4 +330,5 @@ static struct kunit_suite fpga_mgr_suite = {
 
 kunit_test_suite(fpga_mgr_suite);
 
+MODULE_DESCRIPTION("KUnit test for the FPGA Manager");
 MODULE_LICENSE("GPL");

drivers/fpga/tests/fpga-region-test.c

@@ -214,4 +214,5 @@ static struct kunit_suite fpga_region_suite = {
 
 kunit_test_suite(fpga_region_suite);
 
+MODULE_DESCRIPTION("KUnit test for the FPGA Region");
 MODULE_LICENSE("GPL");

include/linux/local_lock.h

@@ -52,43 +52,22 @@
 	__local_unlock_irqrestore(lock, flags)
 
 /**
- * localtry_lock_init - Runtime initialize a lock instance
+ * local_lock_init - Runtime initialize a lock instance
  */
-#define localtry_lock_init(lock)		__localtry_lock_init(lock)
+#define local_trylock_init(lock)	__local_trylock_init(lock)
 
 /**
- * localtry_lock - Acquire a per CPU local lock
+ * local_trylock - Try to acquire a per CPU local lock
- * @lock:	The lock variable
- */
-#define localtry_lock(lock)		__localtry_lock(lock)
-
-/**
- * localtry_lock_irq - Acquire a per CPU local lock and disable interrupts
- * @lock:	The lock variable
- */
-#define localtry_lock_irq(lock)		__localtry_lock_irq(lock)
-
-/**
- * localtry_lock_irqsave - Acquire a per CPU local lock, save and disable
- *			 interrupts
- * @lock:	The lock variable
- * @flags:	Storage for interrupt flags
- */
-#define localtry_lock_irqsave(lock, flags)				\
-	__localtry_lock_irqsave(lock, flags)
-
-/**
- * localtry_trylock - Try to acquire a per CPU local lock.
  * @lock:	The lock variable
  *
  * The function can be used in any context such as NMI or HARDIRQ. Due to
  * locking constrains it will _always_ fail to acquire the lock in NMI or
  * HARDIRQ context on PREEMPT_RT.
  */
-#define localtry_trylock(lock)		__localtry_trylock(lock)
+#define local_trylock(lock)		__local_trylock(lock)
 
 /**
- * localtry_trylock_irqsave - Try to acquire a per CPU local lock, save and disable
+ * local_trylock_irqsave - Try to acquire a per CPU local lock, save and disable
  *			   interrupts if acquired
  * @lock:	The lock variable
  * @flags:	Storage for interrupt flags
@@ -97,29 +76,8 @@
  * locking constrains it will _always_ fail to acquire the lock in NMI or
  * HARDIRQ context on PREEMPT_RT.
  */
-#define localtry_trylock_irqsave(lock, flags)				\
+#define local_trylock_irqsave(lock, flags)			\
-	__localtry_trylock_irqsave(lock, flags)
+	__local_trylock_irqsave(lock, flags)
-
-/**
- * local_unlock - Release a per CPU local lock
- * @lock:	The lock variable
- */
-#define localtry_unlock(lock)		__localtry_unlock(lock)
-
-/**
- * local_unlock_irq - Release a per CPU local lock and enable interrupts
- * @lock:	The lock variable
- */
-#define localtry_unlock_irq(lock)		__localtry_unlock_irq(lock)
-
-/**
- * localtry_unlock_irqrestore - Release a per CPU local lock and restore
- *			      interrupt flags
- * @lock:	The lock variable
- * @flags:      Interrupt flags to restore
- */
-#define localtry_unlock_irqrestore(lock, flags)			\
-	__localtry_unlock_irqrestore(lock, flags)
 
 DEFINE_GUARD(local_lock, local_lock_t __percpu*,
 	     local_lock(_T),

include/linux/local_lock_internal.h

@@ -15,10 +15,11 @@ typedef struct {
 #endif
 } local_lock_t;
 
+/* local_trylock() and local_trylock_irqsave() only work with local_trylock_t */
 typedef struct {
 	local_lock_t	llock;
-	unsigned int	acquired;
+	u8		acquired;
-} localtry_lock_t;
+} local_trylock_t;
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 # define LOCAL_LOCK_DEBUG_INIT(lockname)		\
@@ -29,6 +30,9 @@ typedef struct {
 	},						\
 	.owner = NULL,
 
+# define LOCAL_TRYLOCK_DEBUG_INIT(lockname)		\
+	.llock = { LOCAL_LOCK_DEBUG_INIT((lockname).llock) },
+
 static inline void local_lock_acquire(local_lock_t *l)
 {
 	lock_map_acquire(&l->dep_map);
@@ -56,6 +60,7 @@ static inline void local_lock_debug_init(local_lock_t *l)
 }
 #else /* CONFIG_DEBUG_LOCK_ALLOC */
 # define LOCAL_LOCK_DEBUG_INIT(lockname)
+# define LOCAL_TRYLOCK_DEBUG_INIT(lockname)
 static inline void local_lock_acquire(local_lock_t *l) { }
 static inline void local_trylock_acquire(local_lock_t *l) { }
 static inline void local_lock_release(local_lock_t *l) { }
@@ -63,7 +68,7 @@ static inline void local_lock_debug_init(local_lock_t *l) { }
 #endif /* !CONFIG_DEBUG_LOCK_ALLOC */
 
 #define INIT_LOCAL_LOCK(lockname)	{ LOCAL_LOCK_DEBUG_INIT(lockname) }
-#define INIT_LOCALTRY_LOCK(lockname)	{ .llock = { LOCAL_LOCK_DEBUG_INIT(lockname.llock) }}
+#define INIT_LOCAL_TRYLOCK(lockname)	{ LOCAL_TRYLOCK_DEBUG_INIT(lockname) }
 
 #define __local_lock_init(lock)					\
 do {								\
@@ -76,6 +81,8 @@ do {								\
 	local_lock_debug_init(lock);				\
 } while (0)
 
+#define __local_trylock_init(lock) __local_lock_init(lock.llock)
+
 #define __spinlock_nested_bh_init(lock)				\
 do {								\
 	static struct lock_class_key __key;			\
@@ -87,39 +94,105 @@ do {								\
 	local_lock_debug_init(lock);				\
 } while (0)
 
+#define __local_lock_acquire(lock)					\
+	do {								\
+		local_trylock_t *tl;					\
+		local_lock_t *l;					\
+									\
+		l = (local_lock_t *)this_cpu_ptr(lock);			\
+		tl = (local_trylock_t *)l;				\
+		_Generic((lock),					\
+			local_trylock_t *: ({				\
+				lockdep_assert(tl->acquired == 0);	\
+				WRITE_ONCE(tl->acquired, 1);		\
+			}),						\
+			default:(void)0);				\
+		local_lock_acquire(l);					\
+	} while (0)
+
 #define __local_lock(lock)					\
 	do {							\
 		preempt_disable();				\
-		local_lock_acquire(this_cpu_ptr(lock));		\
+		__local_lock_acquire(lock);			\
 	} while (0)
 
 #define __local_lock_irq(lock)					\
 	do {							\
 		local_irq_disable();				\
-		local_lock_acquire(this_cpu_ptr(lock));		\
+		__local_lock_acquire(lock);			\
 	} while (0)
 
 #define __local_lock_irqsave(lock, flags)			\
 	do {							\
 		local_irq_save(flags);				\
-		local_lock_acquire(this_cpu_ptr(lock));		\
+		__local_lock_acquire(lock);			\
+	} while (0)
+
+#define __local_trylock(lock)					\
+	({							\
+		local_trylock_t *tl;				\
+								\
+		preempt_disable();				\
+		tl = this_cpu_ptr(lock);			\
+		if (READ_ONCE(tl->acquired)) {			\
+			preempt_enable();			\
+			tl = NULL;				\
+		} else {					\
+			WRITE_ONCE(tl->acquired, 1);		\
+			local_trylock_acquire(			\
+				(local_lock_t *)tl);		\
+		}						\
+		!!tl;						\
+	})
+
+#define __local_trylock_irqsave(lock, flags)			\
+	({							\
+		local_trylock_t *tl;				\
+								\
+		local_irq_save(flags);				\
+		tl = this_cpu_ptr(lock);			\
+		if (READ_ONCE(tl->acquired)) {			\
+			local_irq_restore(flags);		\
+			tl = NULL;				\
+		} else {					\
+			WRITE_ONCE(tl->acquired, 1);		\
+			local_trylock_acquire(			\
+				(local_lock_t *)tl);		\
+		}						\
+		!!tl;						\
+	})
+
+#define __local_lock_release(lock)					\
+	do {								\
+		local_trylock_t *tl;					\
+		local_lock_t *l;					\
+									\
+		l = (local_lock_t *)this_cpu_ptr(lock);			\
+		tl = (local_trylock_t *)l;				\
+		local_lock_release(l);					\
+		_Generic((lock),					\
+			local_trylock_t *: ({				\
+				lockdep_assert(tl->acquired == 1);	\
+				WRITE_ONCE(tl->acquired, 0);		\
+			}),						\
+			default:(void)0);				\
 	} while (0)
 
 #define __local_unlock(lock)					\
 	do {							\
-		local_lock_release(this_cpu_ptr(lock));		\
+		__local_lock_release(lock);			\
 		preempt_enable();				\
 	} while (0)
 
 #define __local_unlock_irq(lock)				\
 	do {							\
-		local_lock_release(this_cpu_ptr(lock));		\
+		__local_lock_release(lock);			\
 		local_irq_enable();				\
 	} while (0)
 
 #define __local_unlock_irqrestore(lock, flags)			\
 	do {							\
-		local_lock_release(this_cpu_ptr(lock));		\
+		__local_lock_release(lock);			\
 		local_irq_restore(flags);			\
 	} while (0)
 
@@ -132,104 +205,6 @@ do {								\
 #define __local_unlock_nested_bh(lock)				\
 	local_lock_release(this_cpu_ptr(lock))
 
-/* localtry_lock_t variants */
-
-#define __localtry_lock_init(lock)				\
-do {								\
-	__local_lock_init(&(lock)->llock);			\
-	WRITE_ONCE((lock)->acquired, 0);			\
-} while (0)
-
-#define __localtry_lock(lock)					\
-	do {							\
-		localtry_lock_t *lt;				\
-		preempt_disable();				\
-		lt = this_cpu_ptr(lock);			\
-		local_lock_acquire(&lt->llock);			\
-		WRITE_ONCE(lt->acquired, 1);			\
-	} while (0)
-
-#define __localtry_lock_irq(lock)				\
-	do {							\
-		localtry_lock_t *lt;				\
-		local_irq_disable();				\
-		lt = this_cpu_ptr(lock);			\
-		local_lock_acquire(&lt->llock);			\
-		WRITE_ONCE(lt->acquired, 1);			\
-	} while (0)
-
-#define __localtry_lock_irqsave(lock, flags)			\
-	do {							\
-		localtry_lock_t *lt;				\
-		local_irq_save(flags);				\
-		lt = this_cpu_ptr(lock);			\
-		local_lock_acquire(&lt->llock);			\
-		WRITE_ONCE(lt->acquired, 1);			\
-	} while (0)
-
-#define __localtry_trylock(lock)				\
-	({							\
-		localtry_lock_t *lt;				\
-		bool _ret;					\
-								\
-		preempt_disable();				\
-		lt = this_cpu_ptr(lock);			\
-		if (!READ_ONCE(lt->acquired)) {			\
-			WRITE_ONCE(lt->acquired, 1);		\
-			local_trylock_acquire(&lt->llock);	\
-			_ret = true;				\
-		} else {					\
-			_ret = false;				\
-			preempt_enable();			\
-		}						\
-		_ret;						\
-	})
-
-#define __localtry_trylock_irqsave(lock, flags)			\
-	({							\
-		localtry_lock_t *lt;				\
-		bool _ret;					\
-								\
-		local_irq_save(flags);				\
-		lt = this_cpu_ptr(lock);			\
-		if (!READ_ONCE(lt->acquired)) {			\
-			WRITE_ONCE(lt->acquired, 1);		\
-			local_trylock_acquire(&lt->llock);	\
-			_ret = true;				\
-		} else {					\
-			_ret = false;				\
-			local_irq_restore(flags);		\
-		}						\
-		_ret;						\
-	})
-
-#define __localtry_unlock(lock)					\
-	do {							\
-		localtry_lock_t *lt;				\
-		lt = this_cpu_ptr(lock);			\
-		WRITE_ONCE(lt->acquired, 0);			\
-		local_lock_release(&lt->llock);			\
-		preempt_enable();				\
-	} while (0)
-
-#define __localtry_unlock_irq(lock)				\
-	do {							\
-		localtry_lock_t *lt;				\
-		lt = this_cpu_ptr(lock);			\
-		WRITE_ONCE(lt->acquired, 0);			\
-		local_lock_release(&lt->llock);			\
-		local_irq_enable();				\
-	} while (0)
-
-#define __localtry_unlock_irqrestore(lock, flags)		\
-	do {							\
-		localtry_lock_t *lt;				\
-		lt = this_cpu_ptr(lock);			\
-		WRITE_ONCE(lt->acquired, 0);			\
-		local_lock_release(&lt->llock);			\
-		local_irq_restore(flags);			\
-	} while (0)
-
 #else /* !CONFIG_PREEMPT_RT */
 
 /*
@@ -237,16 +212,18 @@ do {								\
  * critical section while staying preemptible.
  */
 typedef spinlock_t local_lock_t;
-typedef spinlock_t localtry_lock_t;
+typedef spinlock_t local_trylock_t;
 
 #define INIT_LOCAL_LOCK(lockname) __LOCAL_SPIN_LOCK_UNLOCKED((lockname))
-#define INIT_LOCALTRY_LOCK(lockname) INIT_LOCAL_LOCK(lockname)
+#define INIT_LOCAL_TRYLOCK(lockname) __LOCAL_SPIN_LOCK_UNLOCKED((lockname))
 
 #define __local_lock_init(l)					\
 	do {							\
 		local_spin_lock_init((l));			\
 	} while (0)
 
+#define __local_trylock_init(l)			__local_lock_init(l)
+
 #define __local_lock(__lock)					\
 	do {							\
 		migrate_disable();				\
@@ -283,17 +260,7 @@ do {								\
 	spin_unlock(this_cpu_ptr((lock)));			\
 } while (0)
 
-/* localtry_lock_t variants */
+#define __local_trylock(lock)					\
-
-#define __localtry_lock_init(lock)			__local_lock_init(lock)
-#define __localtry_lock(lock)				__local_lock(lock)
-#define __localtry_lock_irq(lock)			__local_lock(lock)
-#define __localtry_lock_irqsave(lock, flags)		__local_lock_irqsave(lock, flags)
-#define __localtry_unlock(lock)				__local_unlock(lock)
-#define __localtry_unlock_irq(lock)			__local_unlock(lock)
-#define __localtry_unlock_irqrestore(lock, flags)	__local_unlock_irqrestore(lock, flags)
-
-#define __localtry_trylock(lock)				\
 	({							\
 		int __locked;					\
 								\
@@ -308,11 +275,11 @@ do {								\
 		__locked;					\
 	})
 
-#define __localtry_trylock_irqsave(lock, flags)			\
+#define __local_trylock_irqsave(lock, flags)			\
 	({							\
 		typecheck(unsigned long, flags);		\
 		flags = 0;					\
-		__localtry_trylock(lock);			\
+		__local_trylock(lock);				\
 	})
 
 #endif /* CONFIG_PREEMPT_RT */

include/linux/pgtable.h

@@ -1511,8 +1511,9 @@ static inline void track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot,
 
 /*
  * track_pfn_copy is called when a VM_PFNMAP VMA is about to get the page
- * tables copied during copy_page_range(). On success, stores the pfn to be
+ * tables copied during copy_page_range(). Will store the pfn to be
- * passed to untrack_pfn_copy().
+ * passed to untrack_pfn_copy() only if there is something to be untracked.
+ * Callers should initialize the pfn to 0.
  */
 static inline int track_pfn_copy(struct vm_area_struct *dst_vma,
 		struct vm_area_struct *src_vma, unsigned long *pfn)
@@ -1522,7 +1523,9 @@ static inline int track_pfn_copy(struct vm_area_struct *dst_vma,
 
 /*
  * untrack_pfn_copy is called when a VM_PFNMAP VMA failed to copy during
- * copy_page_range(), but after track_pfn_copy() was already called.
+ * copy_page_range(), but after track_pfn_copy() was already called. Can
+ * be called even if track_pfn_copy() did not actually track anything:
+ * handled internally.
  */
 static inline void untrack_pfn_copy(struct vm_area_struct *dst_vma,
 		unsigned long pfn)

lib/alloc_tag.c

@@ -422,11 +422,20 @@ static int vm_module_tags_populate(void)
 		unsigned long old_shadow_end = ALIGN(phys_end, MODULE_ALIGN);
 		unsigned long new_shadow_end = ALIGN(new_end, MODULE_ALIGN);
 		unsigned long more_pages;
-		unsigned long nr;
+		unsigned long nr = 0;
 
 		more_pages = ALIGN(new_end - phys_end, PAGE_SIZE) >> PAGE_SHIFT;
-		nr = alloc_pages_bulk_node(GFP_KERNEL | __GFP_NOWARN,
+		while (nr < more_pages) {
-					   NUMA_NO_NODE, more_pages, next_page);
+			unsigned long allocated;
+
+			allocated = alloc_pages_bulk_node(GFP_KERNEL | __GFP_NOWARN,
+				NUMA_NO_NODE, more_pages - nr, next_page + nr);
+
+			if (!allocated)
+				break;
+			nr += allocated;
+		}
+
 		if (nr < more_pages ||
 		    vmap_pages_range(phys_end, phys_end + (nr << PAGE_SHIFT), PAGE_KERNEL,
 				     next_page, PAGE_SHIFT) < 0) {

lib/asn1_decoder.c

@@ -518,4 +518,5 @@ int asn1_ber_decoder(const struct asn1_decoder *decoder,
 }
 EXPORT_SYMBOL_GPL(asn1_ber_decoder);
 
+MODULE_DESCRIPTION("Decoder for ASN.1 BER/DER/CER encoded bytestream");
 MODULE_LICENSE("GPL");

lib/iov_iter.c

@@ -1191,7 +1191,7 @@ static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
 			return -ENOMEM;
 		p = *pages;
 		for (int k = 0; k < n; k++) {
-			struct folio *folio = page_folio(page);
+			struct folio *folio = page_folio(page + k);
 			p[k] = page + k;
 			if (!folio_test_slab(folio))
 				folio_get(folio);

lib/tests/slub_kunit.c

@@ -325,4 +325,5 @@ static struct kunit_suite test_suite = {
 };
 kunit_test_suite(test_suite);
 
+MODULE_DESCRIPTION("Kunit tests for slub allocator");
 MODULE_LICENSE("GPL");

lib/ucs2_string.c

@@ -165,4 +165,5 @@ ucs2_as_utf8(u8 *dest, const ucs2_char_t *src, unsigned long maxlength)
 }
 EXPORT_SYMBOL(ucs2_as_utf8);
 
+MODULE_DESCRIPTION("UCS2 string handling");
 MODULE_LICENSE("GPL v2");

lib/zlib_inflate/inflate_syms.c

@@ -18,4 +18,5 @@ EXPORT_SYMBOL(zlib_inflateEnd);
 EXPORT_SYMBOL(zlib_inflateReset);
 EXPORT_SYMBOL(zlib_inflateIncomp); 
 EXPORT_SYMBOL(zlib_inflate_blob);
+MODULE_DESCRIPTION("Data decompression using the deflation algorithm");
 MODULE_LICENSE("GPL");

mm/cma.c

@@ -35,7 +35,7 @@
 struct cma cma_areas[MAX_CMA_AREAS];
 unsigned int cma_area_count;
 
-static int __init __cma_declare_contiguous_nid(phys_addr_t base,
+static int __init __cma_declare_contiguous_nid(phys_addr_t *basep,
 			phys_addr_t size, phys_addr_t limit,
 			phys_addr_t alignment, unsigned int order_per_bit,
 			bool fixed, const char *name, struct cma **res_cma,
@@ -370,7 +370,7 @@ int __init cma_declare_contiguous_multi(phys_addr_t total_size,
 			phys_addr_t align, unsigned int order_per_bit,
 			const char *name, struct cma **res_cma, int nid)
 {
-	phys_addr_t start, end;
+	phys_addr_t start = 0, end;
 	phys_addr_t size, sizesum, sizeleft;
 	struct cma_init_memrange *mrp, *mlp, *failed;
 	struct cma_memrange *cmrp;
@@ -384,7 +384,7 @@ int __init cma_declare_contiguous_multi(phys_addr_t total_size,
 	/*
 	 * First, try it the normal way, producing just one range.
 	 */
-	ret = __cma_declare_contiguous_nid(0, total_size, 0, align,
+	ret = __cma_declare_contiguous_nid(&start, total_size, 0, align,
 			order_per_bit, false, name, res_cma, nid);
 	if (ret != -ENOMEM)
 		goto out;
@@ -580,7 +580,7 @@ int __init cma_declare_contiguous_nid(phys_addr_t base,
 {
 	int ret;
 
-	ret = __cma_declare_contiguous_nid(base, size, limit, alignment,
+	ret = __cma_declare_contiguous_nid(&base, size, limit, alignment,
 			order_per_bit, fixed, name, res_cma, nid);
 	if (ret != 0)
 		pr_err("Failed to reserve %ld MiB\n",
@@ -592,14 +592,14 @@ int __init cma_declare_contiguous_nid(phys_addr_t base,
 	return ret;
 }
 
-static int __init __cma_declare_contiguous_nid(phys_addr_t base,
+static int __init __cma_declare_contiguous_nid(phys_addr_t *basep,
 			phys_addr_t size, phys_addr_t limit,
 			phys_addr_t alignment, unsigned int order_per_bit,
 			bool fixed, const char *name, struct cma **res_cma,
 			int nid)
 {
 	phys_addr_t memblock_end = memblock_end_of_DRAM();
-	phys_addr_t highmem_start;
+	phys_addr_t highmem_start, base = *basep;
 	int ret;
 
 	/*
@@ -722,12 +722,15 @@ static int __init __cma_declare_contiguous_nid(phys_addr_t base,
 	}
 
 	ret = cma_init_reserved_mem(base, size, order_per_bit, name, res_cma);
-	if (ret)
+	if (ret) {
 		memblock_phys_free(base, size);
+		return ret;
+	}
 
 	(*res_cma)->nid = nid;
+	*basep = base;
 
-	return ret;
+	return 0;
 }
 
 static void cma_debug_show_areas(struct cma *cma)

mm/compaction.c

@@ -981,13 +981,13 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
 		}
 
 		if (PageHuge(page)) {
+			const unsigned int order = compound_order(page);
 			/*
 			 * skip hugetlbfs if we are not compacting for pages
 			 * bigger than its order. THPs and other compound pages
 			 * are handled below.
 			 */
 			if (!cc->alloc_contig) {
-				const unsigned int order = compound_order(page);
 
 				if (order <= MAX_PAGE_ORDER) {
 					low_pfn += (1UL << order) - 1;
@@ -1011,8 +1011,8 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
 				 /* Do not report -EBUSY down the chain */
 				if (ret == -EBUSY)
 					ret = 0;
-				low_pfn += compound_nr(page) - 1;
+				low_pfn += (1UL << order) - 1;
-				nr_scanned += compound_nr(page) - 1;
+				nr_scanned += (1UL << order) - 1;
 				goto isolate_fail;
 			}
 

mm/filemap.c

@@ -2244,6 +2244,7 @@ unsigned filemap_get_folios_contig(struct address_space *mapping,
 			*start = folio->index + nr;
 			goto out;
 		}
+		xas_advance(&xas, folio_next_index(folio) - 1);
 		continue;
 put_folio:
 		folio_put(folio);

mm/hugetlb.c

@@ -2271,7 +2271,7 @@ static struct folio *alloc_surplus_hugetlb_folio(struct hstate *h,
 	 * as surplus_pages, otherwise it might confuse
 	 * persistent_huge_pages() momentarily.
 	 */
-	__prep_account_new_huge_page(h, nid);
+	__prep_account_new_huge_page(h, folio_nid(folio));
 
 	/*
 	 * We could have raced with the pool size change.
@@ -3825,6 +3825,7 @@ static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed,
 static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid,
 			      nodemask_t *nodes_allowed)
 {
+	unsigned long persistent_free_count;
 	unsigned long min_count;
 	unsigned long allocated;
 	struct folio *folio;
@@ -3959,8 +3960,24 @@ static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid,
 	 * though, we'll note that we're not allowed to exceed surplus
 	 * and won't grow the pool anywhere else. Not until one of the
 	 * sysctls are changed, or the surplus pages go out of use.
+	 *
+	 * min_count is the expected number of persistent pages, we
+	 * shouldn't calculate min_count by using
+	 * resv_huge_pages + persistent_huge_pages() - free_huge_pages,
+	 * because there may exist free surplus huge pages, and this will
+	 * lead to subtracting twice. Free surplus huge pages come from HVO
+	 * failing to restore vmemmap, see comments in the callers of
+	 * hugetlb_vmemmap_restore_folio(). Thus, we should calculate
+	 * persistent free count first.
 	 */
-	min_count = h->resv_huge_pages + h->nr_huge_pages - h->free_huge_pages;
+	persistent_free_count = h->free_huge_pages;
+	if (h->free_huge_pages > persistent_huge_pages(h)) {
+		if (h->free_huge_pages > h->surplus_huge_pages)
+			persistent_free_count -= h->surplus_huge_pages;
+		else
+			persistent_free_count = 0;
+	}
+	min_count = h->resv_huge_pages + persistent_huge_pages(h) - persistent_free_count;
 	min_count = max(count, min_count);
 	try_to_free_low(h, min_count, nodes_allowed);
 
@@ -4630,7 +4647,7 @@ static void __init hugetlb_sysfs_init(void)
 		err = hugetlb_sysfs_add_hstate(h, hugepages_kobj,
 					 hstate_kobjs, &hstate_attr_group);
 		if (err)
-			pr_err("HugeTLB: Unable to add hstate %s", h->name);
+			pr_err("HugeTLB: Unable to add hstate %s\n", h->name);
 	}
 
 #ifdef CONFIG_NUMA

mm/kasan/kasan_test_c.c

@@ -2127,4 +2127,5 @@ static struct kunit_suite kasan_kunit_test_suite = {
 
 kunit_test_suite(kasan_kunit_test_suite);
 
+MODULE_DESCRIPTION("KUnit tests for checking KASAN bug-detection capabilities");
 MODULE_LICENSE("GPL");

mm/memcontrol.c

@@ -1759,7 +1759,7 @@ void mem_cgroup_print_oom_group(struct mem_cgroup *memcg)
 }
 
 struct memcg_stock_pcp {
-	localtry_lock_t stock_lock;
+	local_trylock_t stock_lock;
 	struct mem_cgroup *cached; /* this never be root cgroup */
 	unsigned int nr_pages;
 
@@ -1774,7 +1774,7 @@ struct memcg_stock_pcp {
 #define FLUSHING_CACHED_CHARGE	0
 };
 static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock) = {
-	.stock_lock = INIT_LOCALTRY_LOCK(stock_lock),
+	.stock_lock = INIT_LOCAL_TRYLOCK(stock_lock),
 };
 static DEFINE_MUTEX(percpu_charge_mutex);
 
@@ -1805,11 +1805,10 @@ static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages,
 	if (nr_pages > MEMCG_CHARGE_BATCH)
 		return ret;
 
-	if (!localtry_trylock_irqsave(&memcg_stock.stock_lock, flags)) {
+	if (gfpflags_allow_spinning(gfp_mask))
-		if (!gfpflags_allow_spinning(gfp_mask))
+		local_lock_irqsave(&memcg_stock.stock_lock, flags);
+	else if (!local_trylock_irqsave(&memcg_stock.stock_lock, flags))
 		return ret;
-		localtry_lock_irqsave(&memcg_stock.stock_lock, flags);
-	}
 
 	stock = this_cpu_ptr(&memcg_stock);
 	stock_pages = READ_ONCE(stock->nr_pages);
@@ -1818,7 +1817,7 @@ static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages,
 		ret = true;
 	}
 
-	localtry_unlock_irqrestore(&memcg_stock.stock_lock, flags);
+	local_unlock_irqrestore(&memcg_stock.stock_lock, flags);
 
 	return ret;
 }
@@ -1857,14 +1856,14 @@ static void drain_local_stock(struct work_struct *dummy)
 	 * drain_stock races is that we always operate on local CPU stock
 	 * here with IRQ disabled
 	 */
-	localtry_lock_irqsave(&memcg_stock.stock_lock, flags);
+	local_lock_irqsave(&memcg_stock.stock_lock, flags);
 
 	stock = this_cpu_ptr(&memcg_stock);
 	old = drain_obj_stock(stock);
 	drain_stock(stock);
 	clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags);
 
-	localtry_unlock_irqrestore(&memcg_stock.stock_lock, flags);
+	local_unlock_irqrestore(&memcg_stock.stock_lock, flags);
 	obj_cgroup_put(old);
 }
 
@@ -1894,7 +1893,7 @@ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
 {
 	unsigned long flags;
 
-	if (!localtry_trylock_irqsave(&memcg_stock.stock_lock, flags)) {
+	if (!local_trylock_irqsave(&memcg_stock.stock_lock, flags)) {
 		/*
 		 * In case of unlikely failure to lock percpu stock_lock
 		 * uncharge memcg directly.
@@ -1907,7 +1906,7 @@ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages)
 		return;
 	}
 	__refill_stock(memcg, nr_pages);
-	localtry_unlock_irqrestore(&memcg_stock.stock_lock, flags);
+	local_unlock_irqrestore(&memcg_stock.stock_lock, flags);
 }
 
 /*
@@ -1964,9 +1963,9 @@ static int memcg_hotplug_cpu_dead(unsigned int cpu)
 	stock = &per_cpu(memcg_stock, cpu);
 
 	/* drain_obj_stock requires stock_lock */
-	localtry_lock_irqsave(&memcg_stock.stock_lock, flags);
+	local_lock_irqsave(&memcg_stock.stock_lock, flags);
 	old = drain_obj_stock(stock);
-	localtry_unlock_irqrestore(&memcg_stock.stock_lock, flags);
+	local_unlock_irqrestore(&memcg_stock.stock_lock, flags);
 
 	drain_stock(stock);
 	obj_cgroup_put(old);
@@ -2787,7 +2786,7 @@ static void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat,
 	unsigned long flags;
 	int *bytes;
 
-	localtry_lock_irqsave(&memcg_stock.stock_lock, flags);
+	local_lock_irqsave(&memcg_stock.stock_lock, flags);
 	stock = this_cpu_ptr(&memcg_stock);
 
 	/*
@@ -2836,7 +2835,7 @@ static void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat,
 	if (nr)
 		__mod_objcg_mlstate(objcg, pgdat, idx, nr);
 
-	localtry_unlock_irqrestore(&memcg_stock.stock_lock, flags);
+	local_unlock_irqrestore(&memcg_stock.stock_lock, flags);
 	obj_cgroup_put(old);
 }
 
@@ -2846,7 +2845,7 @@ static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
 	unsigned long flags;
 	bool ret = false;
 
-	localtry_lock_irqsave(&memcg_stock.stock_lock, flags);
+	local_lock_irqsave(&memcg_stock.stock_lock, flags);
 
 	stock = this_cpu_ptr(&memcg_stock);
 	if (objcg == READ_ONCE(stock->cached_objcg) && stock->nr_bytes >= nr_bytes) {
@@ -2854,7 +2853,7 @@ static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
 		ret = true;
 	}
 
-	localtry_unlock_irqrestore(&memcg_stock.stock_lock, flags);
+	local_unlock_irqrestore(&memcg_stock.stock_lock, flags);
 
 	return ret;
 }
@@ -2946,7 +2945,7 @@ static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes,
 	unsigned long flags;
 	unsigned int nr_pages = 0;
 
-	localtry_lock_irqsave(&memcg_stock.stock_lock, flags);
+	local_lock_irqsave(&memcg_stock.stock_lock, flags);
 
 	stock = this_cpu_ptr(&memcg_stock);
 	if (READ_ONCE(stock->cached_objcg) != objcg) { /* reset if necessary */
@@ -2960,7 +2959,7 @@ static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes,
 		stock->nr_bytes &= (PAGE_SIZE - 1);
 	}
 
-	localtry_unlock_irqrestore(&memcg_stock.stock_lock, flags);
+	local_unlock_irqrestore(&memcg_stock.stock_lock, flags);
 	obj_cgroup_put(old);
 
 	if (nr_pages)

mm/memory.c

@@ -1361,7 +1361,7 @@ copy_page_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma)
 	struct mm_struct *dst_mm = dst_vma->vm_mm;
 	struct mm_struct *src_mm = src_vma->vm_mm;
 	struct mmu_notifier_range range;
-	unsigned long next, pfn;
+	unsigned long next, pfn = 0;
 	bool is_cow;
 	int ret;
 
@@ -2938,11 +2938,11 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd,
 	if (fn) {
 		do {
 			if (create || !pte_none(ptep_get(pte))) {
-				err = fn(pte++, addr, data);
+				err = fn(pte, addr, data);
 				if (err)
 					break;
 			}
-		} while (addr += PAGE_SIZE, addr != end);
+		} while (pte++, addr += PAGE_SIZE, addr != end);
 	}
 	*mask |= PGTBL_PTE_MODIFIED;
 

mm/page_alloc.c

@@ -1400,11 +1400,12 @@ static void free_one_page(struct zone *zone, struct page *page,
 	struct llist_head *llhead;
 	unsigned long flags;
 
-	if (!spin_trylock_irqsave(&zone->lock, flags)) {
 	if (unlikely(fpi_flags & FPI_TRYLOCK)) {
+		if (!spin_trylock_irqsave(&zone->lock, flags)) {
 			add_page_to_zone_llist(zone, page, order);
 			return;
 		}
+	} else {
 		spin_lock_irqsave(&zone->lock, flags);
 	}
 
@@ -2182,23 +2183,15 @@ try_to_claim_block(struct zone *zone, struct page *page,
 }
 
 /*
- * Try finding a free buddy page on the fallback list.
+ * Try to allocate from some fallback migratetype by claiming the entire block,
- *
+ * i.e. converting it to the allocation's start migratetype.
- * This will attempt to claim a whole pageblock for the requested type
- * to ensure grouping of such requests in the future.
- *
- * If a whole block cannot be claimed, steal an individual page, regressing to
- * __rmqueue_smallest() logic to at least break up as little contiguity as
- * possible.
  *
  * The use of signed ints for order and current_order is a deliberate
  * deviation from the rest of this file, to make the for loop
  * condition simpler.
- *
- * Return the stolen page, or NULL if none can be found.
  */
 static __always_inline struct page *
-__rmqueue_fallback(struct zone *zone, int order, int start_migratetype,
+__rmqueue_claim(struct zone *zone, int order, int start_migratetype,
 						unsigned int alloc_flags)
 {
 	struct free_area *area;
@@ -2236,14 +2229,29 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype,
 		page = try_to_claim_block(zone, page, current_order, order,
 					  start_migratetype, fallback_mt,
 					  alloc_flags);
-		if (page)
+		if (page) {
-			goto got_one;
+			trace_mm_page_alloc_extfrag(page, order, current_order,
+						    start_migratetype, fallback_mt);
+			return page;
+		}
 	}
 
-	if (alloc_flags & ALLOC_NOFRAGMENT)
 	return NULL;
+}
+
+/*
+ * Try to steal a single page from some fallback migratetype. Leave the rest of
+ * the block as its current migratetype, potentially causing fragmentation.
+ */
+static __always_inline struct page *
+__rmqueue_steal(struct zone *zone, int order, int start_migratetype)
+{
+	struct free_area *area;
+	int current_order;
+	struct page *page;
+	int fallback_mt;
+	bool claim_block;
 
-	/* No luck claiming pageblock. Find the smallest fallback page */
 	for (current_order = order; current_order < NR_PAGE_ORDERS; current_order++) {
 		area = &(zone->free_area[current_order]);
 		fallback_mt = find_suitable_fallback(area, current_order,
@@ -2253,25 +2261,28 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype,
 
 		page = get_page_from_free_area(area, fallback_mt);
 		page_del_and_expand(zone, page, order, current_order, fallback_mt);
-		goto got_one;
+		trace_mm_page_alloc_extfrag(page, order, current_order,
+					    start_migratetype, fallback_mt);
+		return page;
 	}
 
 	return NULL;
-
-got_one:
-	trace_mm_page_alloc_extfrag(page, order, current_order,
-		start_migratetype, fallback_mt);
-
-	return page;
 }
 
+enum rmqueue_mode {
+	RMQUEUE_NORMAL,
+	RMQUEUE_CMA,
+	RMQUEUE_CLAIM,
+	RMQUEUE_STEAL,
+};
+
 /*
  * Do the hard work of removing an element from the buddy allocator.
  * Call me with the zone->lock already held.
  */
 static __always_inline struct page *
 __rmqueue(struct zone *zone, unsigned int order, int migratetype,
-						unsigned int alloc_flags)
+	  unsigned int alloc_flags, enum rmqueue_mode *mode)
 {
 	struct page *page;
 
@@ -2290,16 +2301,48 @@ __rmqueue(struct zone *zone, unsigned int order, int migratetype,
 		}
 	}
 
+	/*
+	 * First try the freelists of the requested migratetype, then try
+	 * fallbacks modes with increasing levels of fragmentation risk.
+	 *
+	 * The fallback logic is expensive and rmqueue_bulk() calls in
+	 * a loop with the zone->lock held, meaning the freelists are
+	 * not subject to any outside changes. Remember in *mode where
+	 * we found pay dirt, to save us the search on the next call.
+	 */
+	switch (*mode) {
+	case RMQUEUE_NORMAL:
 		page = __rmqueue_smallest(zone, order, migratetype);
-	if (unlikely(!page)) {
+		if (page)
-		if (alloc_flags & ALLOC_CMA)
-			page = __rmqueue_cma_fallback(zone, order);
-
-		if (!page)
-			page = __rmqueue_fallback(zone, order, migratetype,
-						  alloc_flags);
-	}
 			return page;
+		fallthrough;
+	case RMQUEUE_CMA:
+		if (alloc_flags & ALLOC_CMA) {
+			page = __rmqueue_cma_fallback(zone, order);
+			if (page) {
+				*mode = RMQUEUE_CMA;
+				return page;
+			}
+		}
+		fallthrough;
+	case RMQUEUE_CLAIM:
+		page = __rmqueue_claim(zone, order, migratetype, alloc_flags);
+		if (page) {
+			/* Replenished preferred freelist, back to normal mode. */
+			*mode = RMQUEUE_NORMAL;
+			return page;
+		}
+		fallthrough;
+	case RMQUEUE_STEAL:
+		if (!(alloc_flags & ALLOC_NOFRAGMENT)) {
+			page = __rmqueue_steal(zone, order, migratetype);
+			if (page) {
+				*mode = RMQUEUE_STEAL;
+				return page;
+			}
+		}
+	}
+	return NULL;
 }
 
 /*
@@ -2311,17 +2354,19 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order,
 			unsigned long count, struct list_head *list,
 			int migratetype, unsigned int alloc_flags)
 {
+	enum rmqueue_mode rmqm = RMQUEUE_NORMAL;
 	unsigned long flags;
 	int i;
 
-	if (!spin_trylock_irqsave(&zone->lock, flags)) {
+	if (unlikely(alloc_flags & ALLOC_TRYLOCK)) {
-		if (unlikely(alloc_flags & ALLOC_TRYLOCK))
+		if (!spin_trylock_irqsave(&zone->lock, flags))
 			return 0;
+	} else {
 		spin_lock_irqsave(&zone->lock, flags);
 	}
 	for (i = 0; i < count; ++i) {
 		struct page *page = __rmqueue(zone, order, migratetype,
-								alloc_flags);
+					      alloc_flags, &rmqm);
 		if (unlikely(page == NULL))
 			break;
 
@@ -2937,15 +2982,18 @@ struct page *rmqueue_buddy(struct zone *preferred_zone, struct zone *zone,
 
 	do {
 		page = NULL;
-		if (!spin_trylock_irqsave(&zone->lock, flags)) {
+		if (unlikely(alloc_flags & ALLOC_TRYLOCK)) {
-			if (unlikely(alloc_flags & ALLOC_TRYLOCK))
+			if (!spin_trylock_irqsave(&zone->lock, flags))
 				return NULL;
+		} else {
 			spin_lock_irqsave(&zone->lock, flags);
 		}
 		if (alloc_flags & ALLOC_HIGHATOMIC)
 			page = __rmqueue_smallest(zone, order, MIGRATE_HIGHATOMIC);
 		if (!page) {
-			page = __rmqueue(zone, order, migratetype, alloc_flags);
+			enum rmqueue_mode rmqm = RMQUEUE_NORMAL;
+
+			page = __rmqueue(zone, order, migratetype, alloc_flags, &rmqm);
 
 			/*
 			 * If the allocation fails, allow OOM handling and

mm/userfaultfd.c

@@ -1902,6 +1902,14 @@ struct vm_area_struct *userfaultfd_clear_vma(struct vma_iterator *vmi,
 					     unsigned long end)
 {
 	struct vm_area_struct *ret;
+	bool give_up_on_oom = false;
+
+	/*
+	 * If we are modifying only and not splitting, just give up on the merge
+	 * if OOM prevents us from merging successfully.
+	 */
+	if (start == vma->vm_start && end == vma->vm_end)
+		give_up_on_oom = true;
 
 	/* Reset ptes for the whole vma range if wr-protected */
 	if (userfaultfd_wp(vma))
@@ -1909,7 +1917,7 @@ struct vm_area_struct *userfaultfd_clear_vma(struct vma_iterator *vmi,
 
 	ret = vma_modify_flags_uffd(vmi, prev, vma, start, end,
 				    vma->vm_flags & ~__VM_UFFD_FLAGS,
-				    NULL_VM_UFFD_CTX);
+				    NULL_VM_UFFD_CTX, give_up_on_oom);
 
 	/*
 	 * In the vma_merge() successful mprotect-like case 8:
@@ -1960,7 +1968,8 @@ int userfaultfd_register_range(struct userfaultfd_ctx *ctx,
 		new_flags = (vma->vm_flags & ~__VM_UFFD_FLAGS) | vm_flags;
 		vma = vma_modify_flags_uffd(&vmi, prev, vma, start, vma_end,
 					    new_flags,
-					    (struct vm_userfaultfd_ctx){ctx});
+					    (struct vm_userfaultfd_ctx){ctx},
+					    /* give_up_on_oom = */false);
 		if (IS_ERR(vma))
 			return PTR_ERR(vma);
 

mm/vma.c

@@ -666,6 +666,9 @@ static void vmg_adjust_set_range(struct vma_merge_struct *vmg)
 /*
  * Actually perform the VMA merge operation.
  *
+ * IMPORTANT: We guarantee that, should vmg->give_up_on_oom is set, to not
+ * modify any VMAs or cause inconsistent state should an OOM condition arise.
+ *
  * Returns 0 on success, or an error value on failure.
  */
 static int commit_merge(struct vma_merge_struct *vmg)
@@ -685,6 +688,12 @@ static int commit_merge(struct vma_merge_struct *vmg)
 
 	init_multi_vma_prep(&vp, vma, vmg);
 
+	/*
+	 * If vmg->give_up_on_oom is set, we're safe, because we don't actually
+	 * manipulate any VMAs until we succeed at preallocation.
+	 *
+	 * Past this point, we will not return an error.
+	 */
 	if (vma_iter_prealloc(vmg->vmi, vma))
 		return -ENOMEM;
 
@@ -915,6 +924,12 @@ static __must_check struct vm_area_struct *vma_merge_existing_range(
 		if (anon_dup)
 			unlink_anon_vmas(anon_dup);
 
+		/*
+		 * We've cleaned up any cloned anon_vma's, no VMAs have been
+		 * modified, no harm no foul if the user requests that we not
+		 * report this and just give up, leaving the VMAs unmerged.
+		 */
+		if (!vmg->give_up_on_oom)
 			vmg->state = VMA_MERGE_ERROR_NOMEM;
 		return NULL;
 	}
@@ -926,6 +941,14 @@ static __must_check struct vm_area_struct *vma_merge_existing_range(
 abort:
 	vma_iter_set(vmg->vmi, start);
 	vma_iter_load(vmg->vmi);
+
+	/*
+	 * This means we have failed to clone anon_vma's correctly, but no
+	 * actual changes to VMAs have occurred, so no harm no foul - if the
+	 * user doesn't want this reported and instead just wants to give up on
+	 * the merge, allow it.
+	 */
+	if (!vmg->give_up_on_oom)
 		vmg->state = VMA_MERGE_ERROR_NOMEM;
 	return NULL;
 }
@@ -1068,6 +1091,10 @@ int vma_expand(struct vma_merge_struct *vmg)
 		/* This should already have been checked by this point. */
 		VM_WARN_ON_VMG(!can_merge_remove_vma(next), vmg);
 		vma_start_write(next);
+		/*
+		 * In this case we don't report OOM, so vmg->give_up_on_mm is
+		 * safe.
+		 */
 		ret = dup_anon_vma(middle, next, &anon_dup);
 		if (ret)
 			return ret;
@@ -1090,9 +1117,15 @@ int vma_expand(struct vma_merge_struct *vmg)
 	return 0;
 
 nomem:
-	vmg->state = VMA_MERGE_ERROR_NOMEM;
 	if (anon_dup)
 		unlink_anon_vmas(anon_dup);
+	/*
+	 * If the user requests that we just give upon OOM, we are safe to do so
+	 * here, as commit merge provides this contract to us. Nothing has been
+	 * changed - no harm no foul, just don't report it.
+	 */
+	if (!vmg->give_up_on_oom)
+		vmg->state = VMA_MERGE_ERROR_NOMEM;
 	return -ENOMEM;
 }
 
@@ -1534,6 +1567,13 @@ static struct vm_area_struct *vma_modify(struct vma_merge_struct *vmg)
 	if (vmg_nomem(vmg))
 		return ERR_PTR(-ENOMEM);
 
+	/*
+	 * Split can fail for reasons other than OOM, so if the user requests
+	 * this it's probably a mistake.
+	 */
+	VM_WARN_ON(vmg->give_up_on_oom &&
+		   (vma->vm_start != start || vma->vm_end != end));
+
 	/* Split any preceding portion of the VMA. */
 	if (vma->vm_start < start) {
 		int err = split_vma(vmg->vmi, vma, start, 1);
@@ -1602,12 +1642,15 @@ struct vm_area_struct
 		       struct vm_area_struct *vma,
 		       unsigned long start, unsigned long end,
 		       unsigned long new_flags,
-		       struct vm_userfaultfd_ctx new_ctx)
+		       struct vm_userfaultfd_ctx new_ctx,
+		       bool give_up_on_oom)
 {
 	VMG_VMA_STATE(vmg, vmi, prev, vma, start, end);
 
 	vmg.flags = new_flags;
 	vmg.uffd_ctx = new_ctx;
+	if (give_up_on_oom)
+		vmg.give_up_on_oom = true;
 
 	return vma_modify(&vmg);
 }

mm/vma.h

@@ -114,6 +114,12 @@ struct vma_merge_struct {
 	 */
 	bool just_expand :1;
 
+	/*
+	 * If a merge is possible, but an OOM error occurs, give up and don't
+	 * execute the merge, returning NULL.
+	 */
+	bool give_up_on_oom :1;
+
 	/* Internal flags set during merge process: */
 
 	/*
@@ -255,7 +261,8 @@ __must_check struct vm_area_struct
 		       struct vm_area_struct *vma,
 		       unsigned long start, unsigned long end,
 		       unsigned long new_flags,
-		       struct vm_userfaultfd_ctx new_ctx);
+		       struct vm_userfaultfd_ctx new_ctx,
+		       bool give_up_on_oom);
 
 __must_check struct vm_area_struct
 *vma_merge_new_range(struct vma_merge_struct *vmg);

samples/livepatch/livepatch-callbacks-busymod.c

@@ -56,4 +56,5 @@ static void livepatch_callbacks_mod_exit(void)
 
 module_init(livepatch_callbacks_mod_init);
 module_exit(livepatch_callbacks_mod_exit);
+MODULE_DESCRIPTION("Live patching demo for (un)patching callbacks, support module");
 MODULE_LICENSE("GPL");

samples/livepatch/livepatch-callbacks-demo.c

@@ -192,5 +192,6 @@ static void livepatch_callbacks_demo_exit(void)
 
 module_init(livepatch_callbacks_demo_init);
 module_exit(livepatch_callbacks_demo_exit);
+MODULE_DESCRIPTION("Live patching demo for (un)patching callbacks");
 MODULE_LICENSE("GPL");
 MODULE_INFO(livepatch, "Y");

samples/livepatch/livepatch-callbacks-mod.c

@@ -38,4 +38,5 @@ static void livepatch_callbacks_mod_exit(void)
 
 module_init(livepatch_callbacks_mod_init);
 module_exit(livepatch_callbacks_mod_exit);
+MODULE_DESCRIPTION("Live patching demo for (un)patching callbacks, support module");
 MODULE_LICENSE("GPL");

samples/livepatch/livepatch-sample.c

@@ -66,5 +66,6 @@ static void livepatch_exit(void)
 
 module_init(livepatch_init);
 module_exit(livepatch_exit);
+MODULE_DESCRIPTION("Kernel Live Patching Sample Module");
 MODULE_LICENSE("GPL");
 MODULE_INFO(livepatch, "Y");

samples/livepatch/livepatch-shadow-fix1.c

@@ -168,5 +168,6 @@ static void livepatch_shadow_fix1_exit(void)
 
 module_init(livepatch_shadow_fix1_init);
 module_exit(livepatch_shadow_fix1_exit);
+MODULE_DESCRIPTION("Live patching demo for shadow variables");
 MODULE_LICENSE("GPL");
 MODULE_INFO(livepatch, "Y");

samples/livepatch/livepatch-shadow-fix2.c

@@ -128,5 +128,6 @@ static void livepatch_shadow_fix2_exit(void)
 
 module_init(livepatch_shadow_fix2_init);
 module_exit(livepatch_shadow_fix2_exit);
+MODULE_DESCRIPTION("Live patching demo for shadow variables");
 MODULE_LICENSE("GPL");
 MODULE_INFO(livepatch, "Y");

tools/testing/selftests/mincore/mincore_selftest.c

@@ -283,8 +283,7 @@ TEST(check_file_mmap)
 
 /*
  * Test mincore() behavior on a page backed by a tmpfs file.  This test
- * performs the same steps as the previous one. However, we don't expect
+ * performs the same steps as the previous one.
- * any readahead in this case.
  */
 TEST(check_tmpfs_mmap)
 {
@@ -295,7 +294,6 @@ TEST(check_tmpfs_mmap)
 	int page_size;
 	int fd;
 	int i;
-	int ra_pages = 0;
 
 	page_size = sysconf(_SC_PAGESIZE);
 	vec_size = FILE_SIZE / page_size;
@@ -338,8 +336,7 @@ TEST(check_tmpfs_mmap)
 	}
 
 	/*
-	 * Touch a page in the middle of the mapping. We expect only
+	 * Touch a page in the middle of the mapping.
-	 * that page to be fetched into memory.
 	 */
 	addr[FILE_SIZE / 2] = 1;
 	retval = mincore(addr, FILE_SIZE, vec);
@@ -348,15 +345,6 @@ TEST(check_tmpfs_mmap)
 		TH_LOG("Page not found in memory after use");
 	}
 
-	i = FILE_SIZE / 2 / page_size + 1;
-	while (i < vec_size && vec[i]) {
-		ra_pages++;
-		i++;
-	}
-	ASSERT_EQ(ra_pages, 0) {
-		TH_LOG("Read-ahead pages found in memory");
-	}
-
 	munmap(addr, FILE_SIZE);
 	close(fd);
 	free(vec);

tools/testing/selftests/mm/charge_reserved_hugetlb.sh

@@ -29,7 +29,7 @@ fi
 if [[ $cgroup2 ]]; then
   cgroup_path=$(mount -t cgroup2 | head -1 | awk '{print $3}')
   if [[ -z "$cgroup_path" ]]; then
-    cgroup_path=/dev/cgroup/memory
+    cgroup_path=$(mktemp -d)
     mount -t cgroup2 none $cgroup_path
     do_umount=1
   fi
@@ -37,7 +37,7 @@ if [[ $cgroup2 ]]; then
 else
   cgroup_path=$(mount -t cgroup | grep ",hugetlb" | awk '{print $3}')
   if [[ -z "$cgroup_path" ]]; then
-    cgroup_path=/dev/cgroup/memory
+    cgroup_path=$(mktemp -d)
     mount -t cgroup memory,hugetlb $cgroup_path
     do_umount=1
   fi

tools/testing/selftests/mm/cow.c

@@ -293,7 +293,7 @@ static void do_test_vmsplice_in_parent(char *mem, size_t size,
 		.iov_base = mem,
 		.iov_len = size,
 	};
-	ssize_t cur, total, transferred;
+	ssize_t cur, total, transferred = 0;
 	struct comm_pipes comm_pipes;
 	char *old, *new;
 	int ret, fds[2];

tools/testing/selftests/mm/hugetlb_reparenting_test.sh

@@ -23,7 +23,7 @@ fi
 if [[ $cgroup2 ]]; then
   CGROUP_ROOT=$(mount -t cgroup2 | head -1 | awk '{print $3}')
   if [[ -z "$CGROUP_ROOT" ]]; then
-    CGROUP_ROOT=/dev/cgroup/memory
+    CGROUP_ROOT=$(mktemp -d)
     mount -t cgroup2 none $CGROUP_ROOT
     do_umount=1
   fi

tools/testing/shared/linux.c

@@ -150,7 +150,7 @@ void kmem_cache_free(struct kmem_cache *cachep, void *objp)
 void kmem_cache_free_bulk(struct kmem_cache *cachep, size_t size, void **list)
 {
 	if (kmalloc_verbose)
-		pr_debug("Bulk free %p[0-%lu]\n", list, size - 1);
+		pr_debug("Bulk free %p[0-%zu]\n", list, size - 1);
 
 	pthread_mutex_lock(&cachep->lock);
 	for (int i = 0; i < size; i++)
@@ -168,7 +168,7 @@ int kmem_cache_alloc_bulk(struct kmem_cache *cachep, gfp_t gfp, size_t size,
 	size_t i;
 
 	if (kmalloc_verbose)
-		pr_debug("Bulk alloc %lu\n", size);
+		pr_debug("Bulk alloc %zu\n", size);
 
 	pthread_mutex_lock(&cachep->lock);
 	if (cachep->nr_objs >= size) {

tools/testing/shared/linux/cleanup.h

@@ -0,0 +1,2 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include "../../../../include/linux/cleanup.h"