Merge branches 'akpm' and 'akpm-hotfixes' (patches from Andrew)

Merge yet more updates and hotfixes from Andrew Morton:
 "Post-linux-next material, based upon latest upstream to catch the
  now-merged dependencies:

   - 10 patches.

     Subsystems affected by this patch series: mm (vmstat and migration)
     and compat.

  And bunch of hotfixes, mostly cc:stable:

   - 8 patches.

     Subsystems affected by this patch series: mm (hmm, hugetlb, vmscan,
     pagealloc, pagemap, kmemleak, mempolicy, and memblock)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  arch: remove compat_alloc_user_space
  compat: remove some compat entry points
  mm: simplify compat numa syscalls
  mm: simplify compat_sys_move_pages
  kexec: avoid compat_alloc_user_space
  kexec: move locking into do_kexec_load
  mm: migrate: change to use bool type for 'page_was_mapped'
  mm: migrate: fix the incorrect function name in comments
  mm: migrate: introduce a local variable to get the number of pages
  mm/vmstat: protect per cpu variables with preempt disable on RT

* emailed hotfixes from Andrew Morton <akpm@linux-foundation.org>:
  nds32/setup: remove unused memblock_region variable in setup_memory()
  mm/mempolicy: fix a race between offset_il_node and mpol_rebind_task
  mm/kmemleak: allow __GFP_NOLOCKDEP passed to kmemleak's gfp
  mmap_lock: change trace and locking order
  mm/page_alloc.c: avoid accessing uninitialized pcp page migratetype
  mm,vmscan: fix divide by zero in get_scan_count
  mm/hugetlb: initialize hugetlb_usage in mm_init
  mm/hmm: bypass devmap pte when all pfn requested flags are fulfilled

arch/arm64/include/asm/compat.h

@@ -107,11 +107,6 @@ struct compat_statfs {
 #define compat_user_stack_pointer() (user_stack_pointer(task_pt_regs(current)))
 #define COMPAT_MINSIGSTKSZ	2048
 
-static inline void __user *arch_compat_alloc_user_space(long len)
-{
-	return (void __user *)compat_user_stack_pointer() - len;
-}
-
 struct compat_ipc64_perm {
 	compat_key_t key;
 	__compat_uid32_t uid;

arch/arm64/include/asm/uaccess.h

@@ -430,17 +430,6 @@ extern unsigned long __must_check __arch_copy_to_user(void __user *to, const voi
 	__actu_ret;							\
 })
 
-extern unsigned long __must_check __arch_copy_in_user(void __user *to, const void __user *from, unsigned long n);
-#define raw_copy_in_user(to, from, n)					\
-({									\
-	unsigned long __aciu_ret;					\
-	uaccess_ttbr0_enable();						\
-	__aciu_ret = __arch_copy_in_user(__uaccess_mask_ptr(to),	\
-				    __uaccess_mask_ptr(from), (n));	\
-	uaccess_ttbr0_disable();					\
-	__aciu_ret;							\
-})
-
 #define INLINE_COPY_TO_USER
 #define INLINE_COPY_FROM_USER
 

arch/arm64/include/asm/unistd32.h

@@ -649,11 +649,11 @@ __SYSCALL(__NR_inotify_add_watch, sys_inotify_add_watch)
 #define __NR_inotify_rm_watch 318
 __SYSCALL(__NR_inotify_rm_watch, sys_inotify_rm_watch)
 #define __NR_mbind 319
-__SYSCALL(__NR_mbind, compat_sys_mbind)
+__SYSCALL(__NR_mbind, sys_mbind)
 #define __NR_get_mempolicy 320
-__SYSCALL(__NR_get_mempolicy, compat_sys_get_mempolicy)
+__SYSCALL(__NR_get_mempolicy, sys_get_mempolicy)
 #define __NR_set_mempolicy 321
-__SYSCALL(__NR_set_mempolicy, compat_sys_set_mempolicy)
+__SYSCALL(__NR_set_mempolicy, sys_set_mempolicy)
 #define __NR_openat 322
 __SYSCALL(__NR_openat, compat_sys_openat)
 #define __NR_mkdirat 323
@@ -699,7 +699,7 @@ __SYSCALL(__NR_tee, sys_tee)
 #define __NR_vmsplice 343
 __SYSCALL(__NR_vmsplice, sys_vmsplice)
 #define __NR_move_pages 344
-__SYSCALL(__NR_move_pages, compat_sys_move_pages)
+__SYSCALL(__NR_move_pages, sys_move_pages)
 #define __NR_getcpu 345
 __SYSCALL(__NR_getcpu, sys_getcpu)
 #define __NR_epoll_pwait 346
@@ -811,7 +811,7 @@ __SYSCALL(__NR_rseq, sys_rseq)
 #define __NR_io_pgetevents 399
 __SYSCALL(__NR_io_pgetevents, compat_sys_io_pgetevents)
 #define __NR_migrate_pages 400
-__SYSCALL(__NR_migrate_pages, compat_sys_migrate_pages)
+__SYSCALL(__NR_migrate_pages, sys_migrate_pages)
 #define __NR_kexec_file_load 401
 __SYSCALL(__NR_kexec_file_load, sys_kexec_file_load)
 /* 402 is unused */

arch/arm64/lib/Makefile

 # SPDX-License-Identifier: GPL-2.0
 lib-y		:= clear_user.o delay.o copy_from_user.o		\
-		   copy_to_user.o copy_in_user.o copy_page.o		\
+		   copy_to_user.o copy_page.o				\
 		   clear_page.o csum.o insn.o memchr.o memcpy.o		\
 		   memset.o memcmp.o strcmp.o strncmp.o strlen.o	\
 		   strnlen.o strchr.o strrchr.o tishift.o

arch/arm64/lib/copy_in_user.S

-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copy from user space to user space
- *
- * Copyright (C) 2012 ARM Ltd.
- */
-
-#include <linux/linkage.h>
-
-#include <asm/asm-uaccess.h>
-#include <asm/assembler.h>
-#include <asm/cache.h>
-
-/*
- * Copy from user space to user space (alignment handled by the hardware)
- *
- * Parameters:
- *	x0 - to
- *	x1 - from
- *	x2 - n
- * Returns:
- *	x0 - bytes not copied
- */
-	.macro ldrb1 reg, ptr, val
-	user_ldst 9998f, ldtrb, \reg, \ptr, \val
-	.endm
-
-	.macro strb1 reg, ptr, val
-	user_ldst 9998f, sttrb, \reg, \ptr, \val
-	.endm
-
-	.macro ldrh1 reg, ptr, val
-	user_ldst 9997f, ldtrh, \reg, \ptr, \val
-	.endm
-
-	.macro strh1 reg, ptr, val
-	user_ldst 9997f, sttrh, \reg, \ptr, \val
-	.endm
-
-	.macro ldr1 reg, ptr, val
-	user_ldst 9997f, ldtr, \reg, \ptr, \val
-	.endm
-
-	.macro str1 reg, ptr, val
-	user_ldst 9997f, sttr, \reg, \ptr, \val
-	.endm
-
-	.macro ldp1 reg1, reg2, ptr, val
-	user_ldp 9997f, \reg1, \reg2, \ptr, \val
-	.endm
-
-	.macro stp1 reg1, reg2, ptr, val
-	user_stp 9997f, \reg1, \reg2, \ptr, \val
-	.endm
-
-end	.req	x5
-srcin	.req	x15
-SYM_FUNC_START(__arch_copy_in_user)
-	add	end, x0, x2
-	mov	srcin, x1
-#include "copy_template.S"
-	mov	x0, #0
-	ret
-SYM_FUNC_END(__arch_copy_in_user)
-EXPORT_SYMBOL(__arch_copy_in_user)
-
-	.section .fixup,"ax"
-	.align	2
-9997:	cmp	dst, dstin
-	b.ne	9998f
-	// Before being absolutely sure we couldn't copy anything, try harder
-USER(9998f, ldtrb tmp1w, [srcin])
-USER(9998f, sttrb tmp1w, [dst])
-	add	dst, dst, #1
-9998:	sub	x0, end, dst			// bytes not copied
-	ret
-	.previous

arch/mips/cavium-octeon/octeon-memcpy.S

@@ -154,8 +154,6 @@ FEXPORT(__raw_copy_from_user)
 EXPORT_SYMBOL(__raw_copy_from_user)
 FEXPORT(__raw_copy_to_user)
 EXPORT_SYMBOL(__raw_copy_to_user)
-FEXPORT(__raw_copy_in_user)
-EXPORT_SYMBOL(__raw_copy_in_user)
 	/*
 	 * Note: dst & src may be unaligned, len may be 0
 	 * Temps

arch/mips/include/asm/compat.h

@@ -96,14 +96,6 @@ struct compat_statfs {
 
 #define COMPAT_OFF_T_MAX	0x7fffffff
 
-static inline void __user *arch_compat_alloc_user_space(long len)
-{
-	struct pt_regs *regs = (struct pt_regs *)
-		((unsigned long) current_thread_info() + THREAD_SIZE - 32) - 1;
-
-	return (void __user *) (regs->regs[29] - len);
-}
-
 struct compat_ipc64_perm {
 	compat_key_t key;
 	__compat_uid32_t uid;

arch/mips/include/asm/uaccess.h

@@ -428,7 +428,6 @@ do {									\
 
 extern size_t __raw_copy_from_user(void *__to, const void *__from, size_t __n);
 extern size_t __raw_copy_to_user(void *__to, const void *__from, size_t __n);
-extern size_t __raw_copy_in_user(void *__to, const void *__from, size_t __n);
 
 static inline unsigned long
 raw_copy_from_user(void *to, const void __user *from, unsigned long n)
@@ -480,31 +479,6 @@ raw_copy_to_user(void __user *to, const void *from, unsigned long n)
 #define INLINE_COPY_FROM_USER
 #define INLINE_COPY_TO_USER
 
-static inline unsigned long
-raw_copy_in_user(void __user *to, const void __user *from, unsigned long n)
-{
-	register void __user *__cu_to_r __asm__("$4");
-	register const void __user *__cu_from_r __asm__("$5");
-	register long __cu_len_r __asm__("$6");
-
-	__cu_to_r = to;
-	__cu_from_r = from;
-	__cu_len_r = n;
-
-	__asm__ __volatile__(
-		".set\tnoreorder\n\t"
-		__MODULE_JAL(__raw_copy_in_user)
-		".set\tnoat\n\t"
-		__UA_ADDU "\t$1, %1, %2\n\t"
-		".set\tat\n\t"
-		".set\treorder"
-		: "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)
-		:
-		: "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31",
-		  DADDI_SCRATCH, "memory");
-	return __cu_len_r;
-}
-
 extern __kernel_size_t __bzero(void __user *addr, __kernel_size_t size);
 
 /*

arch/mips/kernel/syscalls/syscall_n32.tbl

@@ -239,9 +239,9 @@
 228	n32	clock_nanosleep			sys_clock_nanosleep_time32
 229	n32	tgkill				sys_tgkill
 230	n32	utimes				sys_utimes_time32
-231	n32	mbind				compat_sys_mbind
-232	n32	get_mempolicy			compat_sys_get_mempolicy
-233	n32	set_mempolicy			compat_sys_set_mempolicy
+231	n32	mbind				sys_mbind
+232	n32	get_mempolicy			sys_get_mempolicy
+233	n32	set_mempolicy			sys_set_mempolicy
 234	n32	mq_open				compat_sys_mq_open
 235	n32	mq_unlink			sys_mq_unlink
 236	n32	mq_timedsend			sys_mq_timedsend_time32
@@ -258,7 +258,7 @@
 247	n32	inotify_init			sys_inotify_init
 248	n32	inotify_add_watch		sys_inotify_add_watch
 249	n32	inotify_rm_watch		sys_inotify_rm_watch
-250	n32	migrate_pages			compat_sys_migrate_pages
+250	n32	migrate_pages			sys_migrate_pages
 251	n32	openat				sys_openat
 252	n32	mkdirat				sys_mkdirat
 253	n32	mknodat				sys_mknodat
@@ -279,7 +279,7 @@
 268	n32	sync_file_range			sys_sync_file_range
 269	n32	tee				sys_tee
 270	n32	vmsplice			sys_vmsplice
-271	n32	move_pages			compat_sys_move_pages
+271	n32	move_pages			sys_move_pages
 272	n32	set_robust_list			compat_sys_set_robust_list
 273	n32	get_robust_list			compat_sys_get_robust_list
 274	n32	kexec_load			compat_sys_kexec_load

arch/mips/kernel/syscalls/syscall_o32.tbl

@@ -279,9 +279,9 @@
 265	o32	clock_nanosleep			sys_clock_nanosleep_time32
 266	o32	tgkill				sys_tgkill
 267	o32	utimes				sys_utimes_time32
-268	o32	mbind				sys_mbind			compat_sys_mbind
-269	o32	get_mempolicy			sys_get_mempolicy		compat_sys_get_mempolicy
-270	o32	set_mempolicy			sys_set_mempolicy		compat_sys_set_mempolicy
+268	o32	mbind				sys_mbind
+269	o32	get_mempolicy			sys_get_mempolicy
+270	o32	set_mempolicy			sys_set_mempolicy
 271	o32	mq_open				sys_mq_open			compat_sys_mq_open
 272	o32	mq_unlink			sys_mq_unlink
 273	o32	mq_timedsend			sys_mq_timedsend_time32
@@ -298,7 +298,7 @@
 284	o32	inotify_init			sys_inotify_init
 285	o32	inotify_add_watch		sys_inotify_add_watch
 286	o32	inotify_rm_watch		sys_inotify_rm_watch
-287	o32	migrate_pages			sys_migrate_pages		compat_sys_migrate_pages
+287	o32	migrate_pages			sys_migrate_pages
 288	o32	openat				sys_openat			compat_sys_openat
 289	o32	mkdirat				sys_mkdirat
 290	o32	mknodat				sys_mknodat
@@ -319,7 +319,7 @@
 305	o32	sync_file_range			sys_sync_file_range		sys32_sync_file_range
 306	o32	tee				sys_tee
 307	o32	vmsplice			sys_vmsplice
-308	o32	move_pages			sys_move_pages			compat_sys_move_pages
+308	o32	move_pages			sys_move_pages
 309	o32	set_robust_list			sys_set_robust_list		compat_sys_set_robust_list
 310	o32	get_robust_list			sys_get_robust_list		compat_sys_get_robust_list
 311	o32	kexec_load			sys_kexec_load			compat_sys_kexec_load

arch/mips/lib/memcpy.S

@@ -666,8 +666,6 @@ FEXPORT(__raw_copy_from_user)
 EXPORT_SYMBOL(__raw_copy_from_user)
 FEXPORT(__raw_copy_to_user)
 EXPORT_SYMBOL(__raw_copy_to_user)
-FEXPORT(__raw_copy_in_user)
-EXPORT_SYMBOL(__raw_copy_in_user)
 #endif
 	/* Legacy Mode, user <-> user */
 	__BUILD_COPY_USER LEGACY_MODE USEROP USEROP
@@ -703,13 +701,4 @@ EXPORT_SYMBOL(__raw_copy_to_user)
 __BUILD_COPY_USER EVA_MODE KERNELOP USEROP
 END(__raw_copy_to_user)
 
-/*
- * __copy_in_user (EVA)
- */
-
-LEAF(__raw_copy_in_user)
-EXPORT_SYMBOL(__raw_copy_in_user)
-__BUILD_COPY_USER EVA_MODE USEROP USEROP
-END(__raw_copy_in_user)
-
 #endif

arch/nds32/kernel/setup.c

@@ -244,7 +244,6 @@ static void __init setup_memory(void)
 	unsigned long ram_start_pfn;
 	unsigned long free_ram_start_pfn;
 	phys_addr_t memory_start, memory_end;
-	struct memblock_region *region;
 
 	memory_end = memory_start = 0;
 

arch/parisc/include/asm/compat.h

@@ -163,12 +163,6 @@ struct compat_shmid64_ds {
 #define COMPAT_ELF_NGREG 80
 typedef compat_ulong_t compat_elf_gregset_t[COMPAT_ELF_NGREG];
 
-static __inline__ void __user *arch_compat_alloc_user_space(long len)
-{
-	struct pt_regs *regs = &current->thread.regs;
-	return (void __user *)regs->gr[30];
-}
-
 static inline int __is_compat_task(struct task_struct *t)
 {
 	return test_tsk_thread_flag(t, TIF_32BIT);

arch/parisc/include/asm/uaccess.h

@@ -215,8 +215,6 @@ unsigned long __must_check raw_copy_to_user(void __user *dst, const void *src,
 					    unsigned long len);
 unsigned long __must_check raw_copy_from_user(void *dst, const void __user *src,
 					    unsigned long len);
-unsigned long __must_check raw_copy_in_user(void __user *dst, const void __user *src,
-					    unsigned long len);
 #define INLINE_COPY_TO_USER
 #define INLINE_COPY_FROM_USER
 

arch/parisc/kernel/syscalls/syscall.tbl

@@ -292,9 +292,9 @@
 258	32	clock_nanosleep		sys_clock_nanosleep_time32
 258	64	clock_nanosleep		sys_clock_nanosleep
 259	common	tgkill			sys_tgkill
-260	common	mbind			sys_mbind			compat_sys_mbind
-261	common	get_mempolicy		sys_get_mempolicy		compat_sys_get_mempolicy
-262	common	set_mempolicy		sys_set_mempolicy		compat_sys_set_mempolicy
+260	common	mbind			sys_mbind
+261	common	get_mempolicy		sys_get_mempolicy
+262	common	set_mempolicy		sys_set_mempolicy
 # 263 was vserver
 264	common	add_key			sys_add_key
 265	common	request_key		sys_request_key
@@ -331,7 +331,7 @@
 292	64	sync_file_range		sys_sync_file_range
 293	common	tee			sys_tee
 294	common	vmsplice		sys_vmsplice
-295	common	move_pages		sys_move_pages			compat_sys_move_pages
+295	common	move_pages		sys_move_pages
 296	common	getcpu			sys_getcpu
 297	common	epoll_pwait		sys_epoll_pwait			compat_sys_epoll_pwait
 298	common	statfs64		sys_statfs64			compat_sys_statfs64

arch/parisc/lib/memcpy.c

@@ -38,14 +38,6 @@ unsigned long raw_copy_from_user(void *dst, const void __user *src,
 }
 EXPORT_SYMBOL(raw_copy_from_user);
 
-unsigned long raw_copy_in_user(void __user *dst, const void __user *src, unsigned long len)
-{
-	mtsp(get_user_space(), 1);
-	mtsp(get_user_space(), 2);
-	return pa_memcpy((void __force *)dst, (void __force *)src, len);
-}
-
-
 void * memcpy(void * dst,const void *src, size_t count)
 {
 	mtsp(get_kernel_space(), 1);
@@ -54,7 +46,6 @@ void * memcpy(void * dst,const void *src, size_t count)
 	return dst;
 }
 
-EXPORT_SYMBOL(raw_copy_in_user);
 EXPORT_SYMBOL(memcpy);
 
 bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)

arch/powerpc/include/asm/compat.h

@@ -83,22 +83,6 @@ struct compat_statfs {
 
 #define COMPAT_OFF_T_MAX	0x7fffffff
 
-static inline void __user *arch_compat_alloc_user_space(long len)
-{
-	struct pt_regs *regs = current->thread.regs;
-	unsigned long usp = regs->gpr[1];
-
-	/*
-	 * We can't access below the stack pointer in the 32bit ABI and
-	 * can access 288 bytes in the 64bit big-endian ABI,
-	 * or 512 bytes with the new ELFv2 little-endian ABI.
-	 */
-	if (!is_32bit_task())
-		usp -= USER_REDZONE_SIZE;
-
-	return (void __user *) (usp - len);
-}
-
 /*
  * ipc64_perm is actually 32/64bit clean but since the compat layer refers to
  * it we may as well define it.

arch/powerpc/kernel/syscalls/syscall.tbl

@@ -330,10 +330,10 @@
 256	64	sys_debug_setcontext		sys_ni_syscall
 256	spu	sys_debug_setcontext		sys_ni_syscall
 # 257 reserved for vserver
-258	nospu	migrate_pages			sys_migrate_pages		compat_sys_migrate_pages
-259	nospu	mbind				sys_mbind			compat_sys_mbind
-260	nospu	get_mempolicy			sys_get_mempolicy		compat_sys_get_mempolicy
-261	nospu	set_mempolicy			sys_set_mempolicy		compat_sys_set_mempolicy
+258	nospu	migrate_pages			sys_migrate_pages
+259	nospu	mbind				sys_mbind
+260	nospu	get_mempolicy			sys_get_mempolicy
+261	nospu	set_mempolicy			sys_set_mempolicy
 262	nospu	mq_open				sys_mq_open			compat_sys_mq_open
 263	nospu	mq_unlink			sys_mq_unlink
 264	32	mq_timedsend			sys_mq_timedsend_time32
@@ -381,7 +381,7 @@
 298	common	faccessat			sys_faccessat
 299	common	get_robust_list			sys_get_robust_list		compat_sys_get_robust_list
 300	common	set_robust_list			sys_set_robust_list		compat_sys_set_robust_list
-301	common	move_pages			sys_move_pages			compat_sys_move_pages
+301	common	move_pages			sys_move_pages
 302	common	getcpu				sys_getcpu
 303	nospu	epoll_pwait			sys_epoll_pwait			compat_sys_epoll_pwait
 304	32	utimensat			sys_utimensat_time32

arch/s390/include/asm/compat.h

@@ -176,16 +176,6 @@ static inline int is_compat_task(void)
 	return test_thread_flag(TIF_31BIT);
 }
 
-static inline void __user *arch_compat_alloc_user_space(long len)
-{
-	unsigned long stack;
-
-	stack = KSTK_ESP(current);
-	if (is_compat_task())
-		stack &= 0x7fffffffUL;
-	return (void __user *) (stack - len);
-}
-
 #endif
 
 struct compat_ipc64_perm {

arch/s390/include/asm/uaccess.h

@@ -227,9 +227,6 @@ static inline int __get_user_fn(void *x, const void __user *ptr, unsigned long s
 	__get_user(x, ptr);					\
 })
 
-unsigned long __must_check
-raw_copy_in_user(void __user *to, const void __user *from, unsigned long n);
-
 /*
  * Copy a null terminated string from userspace.
  */

arch/s390/kernel/syscalls/syscall.tbl

@@ -274,9 +274,9 @@
 265  common	statfs64		sys_statfs64			compat_sys_statfs64
 266  common	fstatfs64		sys_fstatfs64			compat_sys_fstatfs64
 267  common	remap_file_pages	sys_remap_file_pages		sys_remap_file_pages
-268  common	mbind			sys_mbind			compat_sys_mbind
-269  common	get_mempolicy		sys_get_mempolicy		compat_sys_get_mempolicy
-270  common	set_mempolicy		sys_set_mempolicy		compat_sys_set_mempolicy
+268  common	mbind			sys_mbind			sys_mbind
+269  common	get_mempolicy		sys_get_mempolicy		sys_get_mempolicy
+270  common	set_mempolicy		sys_set_mempolicy		sys_set_mempolicy
 271  common	mq_open			sys_mq_open			compat_sys_mq_open
 272  common	mq_unlink		sys_mq_unlink			sys_mq_unlink
 273  common	mq_timedsend		sys_mq_timedsend		sys_mq_timedsend_time32
@@ -293,7 +293,7 @@
 284  common	inotify_init		sys_inotify_init		sys_inotify_init
 285  common	inotify_add_watch	sys_inotify_add_watch		sys_inotify_add_watch
 286  common	inotify_rm_watch	sys_inotify_rm_watch		sys_inotify_rm_watch
-287  common	migrate_pages		sys_migrate_pages		compat_sys_migrate_pages
+287  common	migrate_pages		sys_migrate_pages		sys_migrate_pages
 288  common	openat			sys_openat			compat_sys_openat
 289  common	mkdirat			sys_mkdirat			sys_mkdirat
 290  common	mknodat			sys_mknodat			sys_mknodat
@@ -317,7 +317,7 @@
 307  common	sync_file_range		sys_sync_file_range		compat_sys_s390_sync_file_range
 308  common	tee			sys_tee				sys_tee
 309  common	vmsplice		sys_vmsplice			sys_vmsplice
-310  common	move_pages		sys_move_pages			compat_sys_move_pages
+310  common	move_pages		sys_move_pages			sys_move_pages
 311  common	getcpu			sys_getcpu			sys_getcpu
 312  common	epoll_pwait		sys_epoll_pwait			compat_sys_epoll_pwait
 313  common	utimes			sys_utimes			sys_utimes_time32

arch/s390/lib/uaccess.c

@@ -204,69 +204,6 @@ unsigned long raw_copy_to_user(void __user *to, const void *from, unsigned long
 }
 EXPORT_SYMBOL(raw_copy_to_user);
 
-static inline unsigned long copy_in_user_mvcos(void __user *to, const void __user *from,
-					       unsigned long size)
-{
-	unsigned long tmp1, tmp2;
-
-	tmp1 = -4096UL;
-	/* FIXME: copy with reduced length. */
-	asm volatile(
-		"   lgr	  0,%[spec]\n"
-		"0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n"
-		"   jz	  2f\n"
-		"1: algr  %0,%3\n"
-		"   slgr  %1,%3\n"
-		"   slgr  %2,%3\n"
-		"   j	  0b\n"
-		"2:slgr  %0,%0\n"
-		"3: \n"
-		EX_TABLE(0b,3b)
-		: "+a" (size), "+a" (to), "+a" (from), "+a" (tmp1), "=a" (tmp2)
-		: [spec] "d" (0x810081UL)
-		: "cc", "memory", "0");
-	return size;
-}
-
-static inline unsigned long copy_in_user_mvc(void __user *to, const void __user *from,
-					     unsigned long size)
-{
-	unsigned long tmp1;
-
-	asm volatile(
-		"   sacf  256\n"
-		"   aghi  %0,-1\n"
-		"   jo	  5f\n"
-		"   bras  %3,3f\n"
-		"0: aghi  %0,257\n"
-		"1: mvc	  0(1,%1),0(%2)\n"
-		"   la	  %1,1(%1)\n"
-		"   la	  %2,1(%2)\n"
-		"   aghi  %0,-1\n"
-		"   jnz	  1b\n"
-		"   j	  5f\n"
-		"2: mvc	  0(256,%1),0(%2)\n"
-		"   la	  %1,256(%1)\n"
-		"   la	  %2,256(%2)\n"
-		"3: aghi  %0,-256\n"
-		"   jnm	  2b\n"
-		"4: ex	  %0,1b-0b(%3)\n"
-		"5: slgr  %0,%0\n"
-		"6: sacf  768\n"
-		EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b)
-		: "+a" (size), "+a" (to), "+a" (from), "=a" (tmp1)
-		: : "cc", "memory");
-	return size;
-}
-
-unsigned long raw_copy_in_user(void __user *to, const void __user *from, unsigned long n)
-{
-	if (copy_with_mvcos())
-		return copy_in_user_mvcos(to, from, n);
-	return copy_in_user_mvc(to, from, n);
-}
-EXPORT_SYMBOL(raw_copy_in_user);
-
 static inline unsigned long clear_user_mvcos(void __user *to, unsigned long size)
 {
 	unsigned long tmp1, tmp2;

arch/sparc/include/asm/compat.h

@@ -116,25 +116,6 @@ struct compat_statfs {
 
 #define COMPAT_OFF_T_MAX	0x7fffffff
 
-#ifdef CONFIG_COMPAT
-static inline void __user *arch_compat_alloc_user_space(long len)
-{
-	struct pt_regs *regs = current_thread_info()->kregs;
-	unsigned long usp = regs->u_regs[UREG_I6];
-
-	if (test_thread_64bit_stack(usp))
-		usp += STACK_BIAS;
-
-	if (test_thread_flag(TIF_32BIT))
-		usp &= 0xffffffffUL;
-
-	usp -= len;
-	usp &= ~0x7UL;
-
-	return (void __user *) usp;
-}
-#endif
-
 struct compat_ipc64_perm {
 	compat_key_t key;
 	__compat_uid32_t uid;

arch/sparc/kernel/process_64.c

@@ -455,7 +455,7 @@ static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
 
 	distance = fp - psp;
 	rval = (csp - distance);
-	if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
+	if (raw_copy_in_user((void __user *)rval, (void __user *)psp, distance))
 		rval = 0;
 	else if (!stack_64bit) {
 		if (put_user(((u32)csp),

arch/sparc/kernel/signal32.c

@@ -435,7 +435,7 @@ static int setup_frame32(struct ksignal *ksig, struct pt_regs *regs,
 			      (_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));
 
 	if (!wsaved) {
-		err |= copy_in_user((u32 __user *)sf,
+		err |= raw_copy_in_user((u32 __user *)sf,
 					(u32 __user *)(regs->u_regs[UREG_FP]),
 					sizeof(struct reg_window32));
 	} else {
@@ -567,7 +567,7 @@ static int setup_rt_frame32(struct ksignal *ksig, struct pt_regs *regs,
 	err |= put_compat_sigset(&sf->mask, oldset, sizeof(compat_sigset_t));
 
 	if (!wsaved) {
-		err |= copy_in_user((u32 __user *)sf,
+		err |= raw_copy_in_user((u32 __user *)sf,
 					(u32 __user *)(regs->u_regs[UREG_FP]),
 					sizeof(struct reg_window32));
 	} else {

arch/sparc/kernel/signal_64.c

@@ -406,7 +406,7 @@ setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
 	err |= copy_to_user(&sf->mask, sigmask_to_save(), sizeof(sigset_t));
 
 	if (!wsaved) {
-		err |= copy_in_user((u64 __user *)sf,
+		err |= raw_copy_in_user((u64 __user *)sf,
 					(u64 __user *)(regs->u_regs[UREG_FP] +
 					   STACK_BIAS),
 					sizeof(struct reg_window));

arch/sparc/kernel/syscalls/syscall.tbl

@@ -365,12 +365,12 @@
 299	common	unshare			sys_unshare
 300	common	set_robust_list		sys_set_robust_list		compat_sys_set_robust_list
 301	common	get_robust_list		sys_get_robust_list		compat_sys_get_robust_list
-302	common	migrate_pages		sys_migrate_pages		compat_sys_migrate_pages
-303	common	mbind			sys_mbind			compat_sys_mbind
-304	common	get_mempolicy		sys_get_mempolicy		compat_sys_get_mempolicy
-305	common	set_mempolicy		sys_set_mempolicy		compat_sys_set_mempolicy
+302	common	migrate_pages		sys_migrate_pages
+303	common	mbind			sys_mbind
+304	common	get_mempolicy		sys_get_mempolicy
+305	common	set_mempolicy		sys_set_mempolicy
 306	common	kexec_load		sys_kexec_load			compat_sys_kexec_load
-307	common	move_pages		sys_move_pages			compat_sys_move_pages
+307	common	move_pages		sys_move_pages
 308	common	getcpu			sys_getcpu
 309	common	epoll_pwait		sys_epoll_pwait			compat_sys_epoll_pwait
 310	32	utimensat		sys_utimensat_time32

arch/x86/entry/syscalls/syscall_32.tbl

@@ -286,7 +286,7 @@
 272	i386	fadvise64_64		sys_ia32_fadvise64_64
 273	i386	vserver
 274	i386	mbind			sys_mbind
-275	i386	get_mempolicy		sys_get_mempolicy		compat_sys_get_mempolicy
+275	i386	get_mempolicy		sys_get_mempolicy
 276	i386	set_mempolicy		sys_set_mempolicy
 277	i386	mq_open			sys_mq_open			compat_sys_mq_open
 278	i386	mq_unlink		sys_mq_unlink
@@ -328,7 +328,7 @@
 314	i386	sync_file_range		sys_ia32_sync_file_range
 315	i386	tee			sys_tee
 316	i386	vmsplice		sys_vmsplice
-317	i386	move_pages		sys_move_pages			compat_sys_move_pages
+317	i386	move_pages		sys_move_pages
 318	i386	getcpu			sys_getcpu
 319	i386	epoll_pwait		sys_epoll_pwait
 320	i386	utimensat		sys_utimensat_time32

arch/x86/entry/syscalls/syscall_64.tbl

@@ -398,7 +398,7 @@
 530	x32	set_robust_list		compat_sys_set_robust_list
 531	x32	get_robust_list		compat_sys_get_robust_list
 532	x32	vmsplice		sys_vmsplice
-533	x32	move_pages		compat_sys_move_pages
+533	x32	move_pages		sys_move_pages
 534	x32	preadv			compat_sys_preadv64
 535	x32	pwritev			compat_sys_pwritev64
 536	x32	rt_tgsigqueueinfo	compat_sys_rt_tgsigqueueinfo

arch/x86/include/asm/compat.h

@@ -156,19 +156,6 @@ struct compat_shmid64_ds {
 	(!!(task_pt_regs(current)->orig_ax & __X32_SYSCALL_BIT))
 #endif
 
-static inline void __user *arch_compat_alloc_user_space(long len)
-{
-	compat_uptr_t sp = task_pt_regs(current)->sp;
-
-	/*
-	 * -128 for the x32 ABI redzone.  For IA32, it is not strictly
-	 * necessary, but not harmful.
-	 */
-	sp -= 128;
-
-	return (void __user *)round_down(sp - len, 16);
-}
-
 static inline bool in_x32_syscall(void)
 {
 #ifdef CONFIG_X86_X32_ABI

arch/x86/include/asm/uaccess_64.h

@@ -58,13 +58,6 @@ raw_copy_to_user(void __user *dst, const void *src, unsigned long size)
 	return copy_user_generic((__force void *)dst, src, size);
 }
 
-static __always_inline __must_check
-unsigned long raw_copy_in_user(void __user *dst, const void __user *src, unsigned long size)
-{
-	return copy_user_generic((__force void *)dst,
-				 (__force void *)src, size);
-}
-
 extern long __copy_user_nocache(void *dst, const void __user *src,
 				unsigned size, int zerorest);
 

include/linux/compat.h

@@ -395,14 +395,6 @@ struct compat_kexec_segment;
 struct compat_mq_attr;
 struct compat_msgbuf;
 
-#define BITS_PER_COMPAT_LONG    (8*sizeof(compat_long_t))
-
-#define BITS_TO_COMPAT_LONGS(bits) DIV_ROUND_UP(bits, BITS_PER_COMPAT_LONG)
-
-long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
-		       unsigned long bitmap_size);
-long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
-		       unsigned long bitmap_size);
 void copy_siginfo_to_external32(struct compat_siginfo *to,
 		const struct kernel_siginfo *from);
 int copy_siginfo_from_user32(kernel_siginfo_t *to,
@@ -519,8 +511,6 @@ extern long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 
 struct epoll_event;	/* fortunately, this one is fixed-layout */
 
-extern void __user *compat_alloc_user_space(unsigned long len);
-
 int compat_restore_altstack(const compat_stack_t __user *uss);
 int __compat_save_altstack(compat_stack_t __user *, unsigned long);
 #define unsafe_compat_save_altstack(uss, sp, label) do { \
@@ -807,26 +797,6 @@ asmlinkage long compat_sys_execve(const char __user *filename, const compat_uptr
 /* mm/fadvise.c: No generic prototype for fadvise64_64 */
 
 /* mm/, CONFIG_MMU only */
-asmlinkage long compat_sys_mbind(compat_ulong_t start, compat_ulong_t len,
-				 compat_ulong_t mode,
-				 compat_ulong_t __user *nmask,
-				 compat_ulong_t maxnode, compat_ulong_t flags);
-asmlinkage long compat_sys_get_mempolicy(int __user *policy,
-					 compat_ulong_t __user *nmask,
-					 compat_ulong_t maxnode,
-					 compat_ulong_t addr,
-					 compat_ulong_t flags);
-asmlinkage long compat_sys_set_mempolicy(int mode, compat_ulong_t __user *nmask,
-					 compat_ulong_t maxnode);
-asmlinkage long compat_sys_migrate_pages(compat_pid_t pid,
-		compat_ulong_t maxnode, const compat_ulong_t __user *old_nodes,
-		const compat_ulong_t __user *new_nodes);
-asmlinkage long compat_sys_move_pages(pid_t pid, compat_ulong_t nr_pages,
-				      __u32 __user *pages,
-				      const int __user *nodes,
-				      int __user *status,
-				      int flags);
-
 asmlinkage long compat_sys_rt_tgsigqueueinfo(compat_pid_t tgid,
 					compat_pid_t pid, int sig,
 					struct compat_siginfo __user *uinfo);
@@ -976,6 +946,15 @@ static inline bool in_compat_syscall(void) { return false; }
 
 #endif /* CONFIG_COMPAT */
 
+#define BITS_PER_COMPAT_LONG    (8*sizeof(compat_long_t))
+
+#define BITS_TO_COMPAT_LONGS(bits) DIV_ROUND_UP(bits, BITS_PER_COMPAT_LONG)
+
+long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
+		       unsigned long bitmap_size);
+long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
+		       unsigned long bitmap_size);
+
 /*
  * Some legacy ABIs like the i386 one use less than natural alignment for 64-bit
  * types, and will need special compat treatment for that.  Most architectures

include/linux/hugetlb.h

@@ -858,6 +858,11 @@ static inline spinlock_t *huge_pte_lockptr(struct hstate *h,
 
 void hugetlb_report_usage(struct seq_file *m, struct mm_struct *mm);
 
+static inline void hugetlb_count_init(struct mm_struct *mm)
+{
+	atomic_long_set(&mm->hugetlb_usage, 0);
+}
+
 static inline void hugetlb_count_add(long l, struct mm_struct *mm)
 {
 	atomic_long_add(l, &mm->hugetlb_usage);
@@ -1042,6 +1047,10 @@ static inline spinlock_t *huge_pte_lockptr(struct hstate *h,
 	return &mm->page_table_lock;
 }
 
+static inline void hugetlb_count_init(struct mm_struct *mm)
+{
+}
+
 static inline void hugetlb_report_usage(struct seq_file *f, struct mm_struct *m)
 {
 }

include/linux/mmap_lock.h

@@ -101,14 +101,14 @@ static inline bool mmap_write_trylock(struct mm_struct *mm)
 
 static inline void mmap_write_unlock(struct mm_struct *mm)
 {
-	up_write(&mm->mmap_lock);
 	__mmap_lock_trace_released(mm, true);
+	up_write(&mm->mmap_lock);
 }
 
 static inline void mmap_write_downgrade(struct mm_struct *mm)
 {
-	downgrade_write(&mm->mmap_lock);
 	__mmap_lock_trace_acquire_returned(mm, false, true);
+	downgrade_write(&mm->mmap_lock);
 }
 
 static inline void mmap_read_lock(struct mm_struct *mm)
@@ -140,8 +140,8 @@ static inline bool mmap_read_trylock(struct mm_struct *mm)
 
 static inline void mmap_read_unlock(struct mm_struct *mm)
 {
-	up_read(&mm->mmap_lock);
 	__mmap_lock_trace_released(mm, false);
+	up_read(&mm->mmap_lock);
 }
 
 static inline bool mmap_read_trylock_non_owner(struct mm_struct *mm)
@@ -155,8 +155,8 @@ static inline bool mmap_read_trylock_non_owner(struct mm_struct *mm)
 
 static inline void mmap_read_unlock_non_owner(struct mm_struct *mm)
 {
-	up_read_non_owner(&mm->mmap_lock);
 	__mmap_lock_trace_released(mm, false);
+	up_read_non_owner(&mm->mmap_lock);
 }
 
 static inline void mmap_assert_locked(struct mm_struct *mm)

include/linux/uaccess.h

@@ -200,16 +200,6 @@ copy_to_user(void __user *to, const void *from, unsigned long n)
 		n = _copy_to_user(to, from, n);
 	return n;
 }
-#ifdef CONFIG_COMPAT
-static __always_inline unsigned long __must_check
-copy_in_user(void __user *to, const void __user *from, unsigned long n)
-{
-	might_fault();
-	if (access_ok(to, n) && access_ok(from, n))
-		n = raw_copy_in_user(to, from, n);
-	return n;
-}
-#endif
 
 #ifndef copy_mc_to_kernel
 /*

include/uapi/asm-generic/unistd.h

@@ -673,15 +673,15 @@ __SYSCALL(__NR_madvise, sys_madvise)
 #define __NR_remap_file_pages 234
 __SYSCALL(__NR_remap_file_pages, sys_remap_file_pages)
 #define __NR_mbind 235
-__SC_COMP(__NR_mbind, sys_mbind, compat_sys_mbind)
+__SYSCALL(__NR_mbind, sys_mbind)
 #define __NR_get_mempolicy 236
-__SC_COMP(__NR_get_mempolicy, sys_get_mempolicy, compat_sys_get_mempolicy)
+__SYSCALL(__NR_get_mempolicy, sys_get_mempolicy)
 #define __NR_set_mempolicy 237
-__SC_COMP(__NR_set_mempolicy, sys_set_mempolicy, compat_sys_set_mempolicy)
+__SYSCALL(__NR_set_mempolicy, sys_set_mempolicy)
 #define __NR_migrate_pages 238
-__SC_COMP(__NR_migrate_pages, sys_migrate_pages, compat_sys_migrate_pages)
+__SYSCALL(__NR_migrate_pages, sys_migrate_pages)
 #define __NR_move_pages 239
-__SC_COMP(__NR_move_pages, sys_move_pages, compat_sys_move_pages)
+__SYSCALL(__NR_move_pages, sys_move_pages)
 #endif
 
 #define __NR_rt_tgsigqueueinfo 240

kernel/compat.c

@@ -269,24 +269,3 @@ get_compat_sigset(sigset_t *set, const compat_sigset_t __user *compat)
 	return 0;
 }
 EXPORT_SYMBOL_GPL(get_compat_sigset);
-
-/*
- * Allocate user-space memory for the duration of a single system call,
- * in order to marshall parameters inside a compat thunk.
- */
-void __user *compat_alloc_user_space(unsigned long len)
-{
-	void __user *ptr;
-
-	/* If len would occupy more than half of the entire compat space... */
-	if (unlikely(len > (((compat_uptr_t)~0) >> 1)))
-		return NULL;
-
-	ptr = arch_compat_alloc_user_space(len);
-
-	if (unlikely(!access_ok(ptr, len)))
-		return NULL;
-
-	return ptr;
-}
-EXPORT_SYMBOL_GPL(compat_alloc_user_space);

kernel/fork.c

@@ -1063,6 +1063,7 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p,
 	mm->pmd_huge_pte = NULL;
 #endif
 	mm_init_uprobes_state(mm);
+	hugetlb_count_init(mm);
 
 	if (current->mm) {
 		mm->flags = current->mm->flags & MMF_INIT_MASK;

kernel/kexec.c

@@ -19,26 +19,9 @@
 
 #include "kexec_internal.h"
 
-static int copy_user_segment_list(struct kimage *image,
-				  unsigned long nr_segments,
-				  struct kexec_segment __user *segments)
-{
-	int ret;
-	size_t segment_bytes;
-
-	/* Read in the segments */
-	image->nr_segments = nr_segments;
-	segment_bytes = nr_segments * sizeof(*segments);
-	ret = copy_from_user(image->segment, segments, segment_bytes);
-	if (ret)
-		ret = -EFAULT;
-
-	return ret;
-}
-
 static int kimage_alloc_init(struct kimage **rimage, unsigned long entry,
 			     unsigned long nr_segments,
-			     struct kexec_segment __user *segments,
+			     struct kexec_segment *segments,
 			     unsigned long flags)
 {
 	int ret;
@@ -58,10 +41,8 @@ static int kimage_alloc_init(struct kimage **rimage, unsigned long entry,
 		return -ENOMEM;
 
 	image->start = entry;
-
-	ret = copy_user_segment_list(image, nr_segments, segments);
-	if (ret)
-		goto out_free_image;
+	image->nr_segments = nr_segments;
+	memcpy(image->segment, segments, nr_segments * sizeof(*segments));
 
 	if (kexec_on_panic) {
 		/* Enable special crash kernel control page alloc policy. */
@@ -104,12 +85,23 @@ static int kimage_alloc_init(struct kimage **rimage, unsigned long entry,
 }
 
 static int do_kexec_load(unsigned long entry, unsigned long nr_segments,
-		struct kexec_segment __user *segments, unsigned long flags)
+		struct kexec_segment *segments, unsigned long flags)
 {
 	struct kimage **dest_image, *image;
 	unsigned long i;
 	int ret;
 
+	/*
+	 * Because we write directly to the reserved memory region when loading
+	 * crash kernels we need a mutex here to prevent multiple crash kernels
+	 * from attempting to load simultaneously, and to prevent a crash kernel
+	 * from loading over the top of a in use crash kernel.
+	 *
+	 * KISS: always take the mutex.
+	 */
+	if (!mutex_trylock(&kexec_mutex))
+		return -EBUSY;
+
 	if (flags & KEXEC_ON_CRASH) {
 		dest_image = &kexec_crash_image;
 		if (kexec_crash_image)
@@ -121,7 +113,8 @@ static int do_kexec_load(unsigned long entry, unsigned long nr_segments,
 	if (nr_segments == 0) {
 		/* Uninstall image */
 		kimage_free(xchg(dest_image, NULL));
-		return 0;
+		ret = 0;
+		goto out_unlock;
 	}
 	if (flags & KEXEC_ON_CRASH) {
 		/*
@@ -134,7 +127,7 @@ static int do_kexec_load(unsigned long entry, unsigned long nr_segments,
 
 	ret = kimage_alloc_init(&image, entry, nr_segments, segments, flags);
 	if (ret)
-		return ret;
+		goto out_unlock;
 
 	if (flags & KEXEC_PRESERVE_CONTEXT)
 		image->preserve_context = 1;
@@ -171,6 +164,8 @@ static int do_kexec_load(unsigned long entry, unsigned long nr_segments,
 		arch_kexec_protect_crashkres();
 
 	kimage_free(image);
+out_unlock:
+	mutex_unlock(&kexec_mutex);
 	return ret;
 }
 
@@ -236,7 +231,8 @@ static inline int kexec_load_check(unsigned long nr_segments,
 SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
 		struct kexec_segment __user *, segments, unsigned long, flags)
 {
-	int result;
+	struct kexec_segment *ksegments;
+	unsigned long result;
 
 	result = kexec_load_check(nr_segments, flags);
 	if (result)
@@ -247,20 +243,12 @@ SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
 		((flags & KEXEC_ARCH_MASK) != KEXEC_ARCH_DEFAULT))
 		return -EINVAL;
 
-	/* Because we write directly to the reserved memory
-	 * region when loading crash kernels we need a mutex here to
-	 * prevent multiple crash  kernels from attempting to load
-	 * simultaneously, and to prevent a crash kernel from loading
-	 * over the top of a in use crash kernel.
-	 *
-	 * KISS: always take the mutex.
-	 */
-	if (!mutex_trylock(&kexec_mutex))
-		return -EBUSY;
-
-	result = do_kexec_load(entry, nr_segments, segments, flags);
+	ksegments = memdup_user(segments, nr_segments * sizeof(ksegments[0]));
+	if (IS_ERR(ksegments))
+		return PTR_ERR(ksegments);
 
-	mutex_unlock(&kexec_mutex);
+	result = do_kexec_load(entry, nr_segments, ksegments, flags);
+	kfree(ksegments);
 
 	return result;
 }
@@ -272,7 +260,7 @@ COMPAT_SYSCALL_DEFINE4(kexec_load, compat_ulong_t, entry,
 		       compat_ulong_t, flags)
 {
 	struct compat_kexec_segment in;
-	struct kexec_segment out, __user *ksegments;
+	struct kexec_segment *ksegments;
 	unsigned long i, result;
 
 	result = kexec_load_check(nr_segments, flags);
@@ -285,37 +273,26 @@ COMPAT_SYSCALL_DEFINE4(kexec_load, compat_ulong_t, entry,
 	if ((flags & KEXEC_ARCH_MASK) == KEXEC_ARCH_DEFAULT)
 		return -EINVAL;
 
-	ksegments = compat_alloc_user_space(nr_segments * sizeof(out));
+	ksegments = kmalloc_array(nr_segments, sizeof(ksegments[0]),
+			GFP_KERNEL);
+	if (!ksegments)
+		return -ENOMEM;
+
 	for (i = 0; i < nr_segments; i++) {
 		result = copy_from_user(&in, &segments[i], sizeof(in));
 		if (result)
-			return -EFAULT;
-
-		out.buf   = compat_ptr(in.buf);
-		out.bufsz = in.bufsz;
-		out.mem   = in.mem;
-		out.memsz = in.memsz;
+			goto fail;
 
-		result = copy_to_user(&ksegments[i], &out, sizeof(out));
-		if (result)
-			return -EFAULT;
+		ksegments[i].buf   = compat_ptr(in.buf);
+		ksegments[i].bufsz = in.bufsz;
+		ksegments[i].mem   = in.mem;
+		ksegments[i].memsz = in.memsz;
 	}
 
-	/* Because we write directly to the reserved memory
-	 * region when loading crash kernels we need a mutex here to
-	 * prevent multiple crash  kernels from attempting to load
-	 * simultaneously, and to prevent a crash kernel from loading
-	 * over the top of a in use crash kernel.
-	 *
-	 * KISS: always take the mutex.
-	 */
-	if (!mutex_trylock(&kexec_mutex))
-		return -EBUSY;
-
 	result = do_kexec_load(entry, nr_segments, ksegments, flags);
 
-	mutex_unlock(&kexec_mutex);
-
+fail:
+	kfree(ksegments);
 	return result;
 }
 #endif

kernel/sys_ni.c

@@ -292,15 +292,10 @@ COND_SYSCALL(process_madvise);
 COND_SYSCALL(process_mrelease);
 COND_SYSCALL(remap_file_pages);
 COND_SYSCALL(mbind);
-COND_SYSCALL_COMPAT(mbind);
 COND_SYSCALL(get_mempolicy);
-COND_SYSCALL_COMPAT(get_mempolicy);
 COND_SYSCALL(set_mempolicy);
-COND_SYSCALL_COMPAT(set_mempolicy);
 COND_SYSCALL(migrate_pages);
-COND_SYSCALL_COMPAT(migrate_pages);
 COND_SYSCALL(move_pages);
-COND_SYSCALL_COMPAT(move_pages);
 
 COND_SYSCALL(perf_event_open);
 COND_SYSCALL(accept4);

mm/hmm.c

@@ -295,10 +295,13 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr,
 		goto fault;
 
 	/*
+	 * Bypass devmap pte such as DAX page when all pfn requested
+	 * flags(pfn_req_flags) are fulfilled.
 	 * Since each architecture defines a struct page for the zero page, just
 	 * fall through and treat it like a normal page.
 	 */
-	if (pte_special(pte) && !is_zero_pfn(pte_pfn(pte))) {
+	if (pte_special(pte) && !pte_devmap(pte) &&
+	    !is_zero_pfn(pte_pfn(pte))) {
 		if (hmm_pte_need_fault(hmm_vma_walk, pfn_req_flags, 0)) {
 			pte_unmap(ptep);
 			return -EFAULT;

mm/kmemleak.c

@@ -113,7 +113,8 @@
 #define BYTES_PER_POINTER	sizeof(void *)
 
 /* GFP bitmask for kmemleak internal allocations */
-#define gfp_kmemleak_mask(gfp)	(((gfp) & (GFP_KERNEL | GFP_ATOMIC)) | \
+#define gfp_kmemleak_mask(gfp)	(((gfp) & (GFP_KERNEL | GFP_ATOMIC | \
+					   __GFP_NOLOCKDEP)) | \
 				 __GFP_NORETRY | __GFP_NOMEMALLOC | \
 				 __GFP_NOWARN)
 

mm/mempolicy.c

@@ -1362,16 +1362,33 @@ static long do_mbind(unsigned long start, unsigned long len,
 /*
  * User space interface with variable sized bitmaps for nodelists.
  */
+static int get_bitmap(unsigned long *mask, const unsigned long __user *nmask,
+		      unsigned long maxnode)
+{
+	unsigned long nlongs = BITS_TO_LONGS(maxnode);
+	int ret;
+
+	if (in_compat_syscall())
+		ret = compat_get_bitmap(mask,
+					(const compat_ulong_t __user *)nmask,
+					maxnode);
+	else
+		ret = copy_from_user(mask, nmask,
+				     nlongs * sizeof(unsigned long));
+
+	if (ret)
+		return -EFAULT;
+
+	if (maxnode % BITS_PER_LONG)
+		mask[nlongs - 1] &= (1UL << (maxnode % BITS_PER_LONG)) - 1;
+
+	return 0;
+}
 
 /* Copy a node mask from user space. */
 static int get_nodes(nodemask_t *nodes, const unsigned long __user *nmask,
 		     unsigned long maxnode)
 {
-	unsigned long k;
-	unsigned long t;
-	unsigned long nlongs;
-	unsigned long endmask;
-
 	--maxnode;
 	nodes_clear(*nodes);
 	if (maxnode == 0 || !nmask)
@@ -1379,49 +1396,29 @@ static int get_nodes(nodemask_t *nodes, const unsigned long __user *nmask,
 	if (maxnode > PAGE_SIZE*BITS_PER_BYTE)
 		return -EINVAL;
 
-	nlongs = BITS_TO_LONGS(maxnode);
-	if ((maxnode % BITS_PER_LONG) == 0)
-		endmask = ~0UL;
-	else
-		endmask = (1UL << (maxnode % BITS_PER_LONG)) - 1;
-
 	/*
 	 * When the user specified more nodes than supported just check
-	 * if the non supported part is all zero.
-	 *
-	 * If maxnode have more longs than MAX_NUMNODES, check
-	 * the bits in that area first. And then go through to
-	 * check the rest bits which equal or bigger than MAX_NUMNODES.
-	 * Otherwise, just check bits [MAX_NUMNODES, maxnode).
-	 */
-	if (nlongs > BITS_TO_LONGS(MAX_NUMNODES)) {
-		for (k = BITS_TO_LONGS(MAX_NUMNODES); k < nlongs; k++) {
-			if (get_user(t, nmask + k))
-				return -EFAULT;
-			if (k == nlongs - 1) {
-				if (t & endmask)
-					return -EINVAL;
-			} else if (t)
-				return -EINVAL;
-		}
-		nlongs = BITS_TO_LONGS(MAX_NUMNODES);
-		endmask = ~0UL;
-	}
-
-	if (maxnode > MAX_NUMNODES && MAX_NUMNODES % BITS_PER_LONG != 0) {
-		unsigned long valid_mask = endmask;
+	 * if the non supported part is all zero, one word at a time,
+	 * starting at the end.
+	 */
+	while (maxnode > MAX_NUMNODES) {
+		unsigned long bits = min_t(unsigned long, maxnode, BITS_PER_LONG);
+		unsigned long t;
 
-		valid_mask &= ~((1UL << (MAX_NUMNODES % BITS_PER_LONG)) - 1);
-		if (get_user(t, nmask + nlongs - 1))
+		if (get_bitmap(&t, &nmask[maxnode / BITS_PER_LONG], bits))
 			return -EFAULT;
-		if (t & valid_mask)
+
+		if (maxnode - bits >= MAX_NUMNODES) {
+			maxnode -= bits;
+		} else {
+			maxnode = MAX_NUMNODES;
+			t &= ~((1UL << (MAX_NUMNODES % BITS_PER_LONG)) - 1);
+		}
+		if (t)
 			return -EINVAL;
 	}
 
-	if (copy_from_user(nodes_addr(*nodes), nmask, nlongs*sizeof(unsigned long)))
-		return -EFAULT;
-	nodes_addr(*nodes)[nlongs-1] &= endmask;
-	return 0;
+	return get_bitmap(nodes_addr(*nodes), nmask, maxnode);
 }
 
 /* Copy a kernel node mask to user space */
@@ -1430,6 +1427,10 @@ static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode,
 {
 	unsigned long copy = ALIGN(maxnode-1, 64) / 8;
 	unsigned int nbytes = BITS_TO_LONGS(nr_node_ids) * sizeof(long);
+	bool compat = in_compat_syscall();
+
+	if (compat)
+		nbytes = BITS_TO_COMPAT_LONGS(nr_node_ids) * sizeof(compat_long_t);
 
 	if (copy > nbytes) {
 		if (copy > PAGE_SIZE)
@@ -1437,7 +1438,13 @@ static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode,
 		if (clear_user((char __user *)mask + nbytes, copy - nbytes))
 			return -EFAULT;
 		copy = nbytes;
+		maxnode = nr_node_ids;
 	}
+
+	if (compat)
+		return compat_put_bitmap((compat_ulong_t __user *)mask,
+					 nodes_addr(*nodes), maxnode);
+
 	return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0;
 }
 
@@ -1642,116 +1649,6 @@ SYSCALL_DEFINE5(get_mempolicy, int __user *, policy,
 	return kernel_get_mempolicy(policy, nmask, maxnode, addr, flags);
 }
 
-#ifdef CONFIG_COMPAT
-
-COMPAT_SYSCALL_DEFINE5(get_mempolicy, int __user *, policy,
-		       compat_ulong_t __user *, nmask,
-		       compat_ulong_t, maxnode,
-		       compat_ulong_t, addr, compat_ulong_t, flags)
-{
-	long err;
-	unsigned long __user *nm = NULL;
-	unsigned long nr_bits, alloc_size;
-	DECLARE_BITMAP(bm, MAX_NUMNODES);
-
-	nr_bits = min_t(unsigned long, maxnode-1, nr_node_ids);
-	alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
-
-	if (nmask)
-		nm = compat_alloc_user_space(alloc_size);
-
-	err = kernel_get_mempolicy(policy, nm, nr_bits+1, addr, flags);
-
-	if (!err && nmask) {
-		unsigned long copy_size;
-		copy_size = min_t(unsigned long, sizeof(bm), alloc_size);
-		err = copy_from_user(bm, nm, copy_size);
-		/* ensure entire bitmap is zeroed */
-		err |= clear_user(nmask, ALIGN(maxnode-1, 8) / 8);
-		err |= compat_put_bitmap(nmask, bm, nr_bits);
-	}
-
-	return err;
-}
-
-COMPAT_SYSCALL_DEFINE3(set_mempolicy, int, mode, compat_ulong_t __user *, nmask,
-		       compat_ulong_t, maxnode)
-{
-	unsigned long __user *nm = NULL;
-	unsigned long nr_bits, alloc_size;
-	DECLARE_BITMAP(bm, MAX_NUMNODES);
-
-	nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES);
-	alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
-
-	if (nmask) {
-		if (compat_get_bitmap(bm, nmask, nr_bits))
-			return -EFAULT;
-		nm = compat_alloc_user_space(alloc_size);
-		if (copy_to_user(nm, bm, alloc_size))
-			return -EFAULT;
-	}
-
-	return kernel_set_mempolicy(mode, nm, nr_bits+1);
-}
-
-COMPAT_SYSCALL_DEFINE6(mbind, compat_ulong_t, start, compat_ulong_t, len,
-		       compat_ulong_t, mode, compat_ulong_t __user *, nmask,
-		       compat_ulong_t, maxnode, compat_ulong_t, flags)
-{
-	unsigned long __user *nm = NULL;
-	unsigned long nr_bits, alloc_size;
-	nodemask_t bm;
-
-	nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES);
-	alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
-
-	if (nmask) {
-		if (compat_get_bitmap(nodes_addr(bm), nmask, nr_bits))
-			return -EFAULT;
-		nm = compat_alloc_user_space(alloc_size);
-		if (copy_to_user(nm, nodes_addr(bm), alloc_size))
-			return -EFAULT;
-	}
-
-	return kernel_mbind(start, len, mode, nm, nr_bits+1, flags);
-}
-
-COMPAT_SYSCALL_DEFINE4(migrate_pages, compat_pid_t, pid,
-		       compat_ulong_t, maxnode,
-		       const compat_ulong_t __user *, old_nodes,
-		       const compat_ulong_t __user *, new_nodes)
-{
-	unsigned long __user *old = NULL;
-	unsigned long __user *new = NULL;
-	nodemask_t tmp_mask;
-	unsigned long nr_bits;
-	unsigned long size;
-
-	nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES);
-	size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
-	if (old_nodes) {
-		if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits))
-			return -EFAULT;
-		old = compat_alloc_user_space(new_nodes ? size * 2 : size);
-		if (new_nodes)
-			new = old + size / sizeof(unsigned long);
-		if (copy_to_user(old, nodes_addr(tmp_mask), size))
-			return -EFAULT;
-	}
-	if (new_nodes) {
-		if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits))
-			return -EFAULT;
-		if (new == NULL)
-			new = compat_alloc_user_space(size);
-		if (copy_to_user(new, nodes_addr(tmp_mask), size))
-			return -EFAULT;
-	}
-	return kernel_migrate_pages(pid, nr_bits + 1, old, new);
-}
-
-#endif /* CONFIG_COMPAT */
-
 bool vma_migratable(struct vm_area_struct *vma)
 {
 	if (vma->vm_flags & (VM_IO | VM_PFNMAP))
@@ -1979,17 +1876,26 @@ unsigned int mempolicy_slab_node(void)
  */
 static unsigned offset_il_node(struct mempolicy *pol, unsigned long n)
 {
-	unsigned nnodes = nodes_weight(pol->nodes);
-	unsigned target;
+	nodemask_t nodemask = pol->nodes;
+	unsigned int target, nnodes;
 	int i;
 	int nid;
+	/*
+	 * The barrier will stabilize the nodemask in a register or on
+	 * the stack so that it will stop changing under the code.
+	 *
+	 * Between first_node() and next_node(), pol->nodes could be changed
+	 * by other threads. So we put pol->nodes in a local stack.
+	 */
+	barrier();
 
+	nnodes = nodes_weight(nodemask);
 	if (!nnodes)
 		return numa_node_id();
 	target = (unsigned int)n % nnodes;
-	nid = first_node(pol->nodes);
+	nid = first_node(nodemask);
 	for (i = 0; i < target; i++)
-		nid = next_node(nid, pol->nodes);
+		nid = next_node(nid, nodemask);
 	return nid;
 }
 

mm/migrate.c

@@ -960,7 +960,7 @@ static int __unmap_and_move(struct page *page, struct page *newpage,
 				int force, enum migrate_mode mode)
 {
 	int rc = -EAGAIN;
-	int page_was_mapped = 0;
+	bool page_was_mapped = false;
 	struct anon_vma *anon_vma = NULL;
 	bool is_lru = !__PageMovable(page);
 
@@ -1008,7 +1008,7 @@ static int __unmap_and_move(struct page *page, struct page *newpage,
 	}
 
 	/*
-	 * By try_to_unmap(), page->mapcount goes down to 0 here. In this case,
+	 * By try_to_migrate(), page->mapcount goes down to 0 here. In this case,
 	 * we cannot notice that anon_vma is freed while we migrates a page.
 	 * This get_anon_vma() delays freeing anon_vma pointer until the end
 	 * of migration. File cache pages are no problem because of page_lock()
@@ -1063,7 +1063,7 @@ static int __unmap_and_move(struct page *page, struct page *newpage,
 		VM_BUG_ON_PAGE(PageAnon(page) && !PageKsm(page) && !anon_vma,
 				page);
 		try_to_migrate(page, 0);
-		page_was_mapped = 1;
+		page_was_mapped = true;
 	}
 
 	if (!page_mapped(page))
@@ -1900,6 +1900,23 @@ static void do_pages_stat_array(struct mm_struct *mm, unsigned long nr_pages,
 	mmap_read_unlock(mm);
 }
 
+static int get_compat_pages_array(const void __user *chunk_pages[],
+				  const void __user * __user *pages,
+				  unsigned long chunk_nr)
+{
+	compat_uptr_t __user *pages32 = (compat_uptr_t __user *)pages;
+	compat_uptr_t p;
+	int i;
+
+	for (i = 0; i < chunk_nr; i++) {
+		if (get_user(p, pages32 + i))
+			return -EFAULT;
+		chunk_pages[i] = compat_ptr(p);
+	}
+
+	return 0;
+}
+
 /*
  * Determine the nodes of a user array of pages and store it in
  * a user array of status.
@@ -1919,8 +1936,15 @@ static int do_pages_stat(struct mm_struct *mm, unsigned long nr_pages,
 		if (chunk_nr > DO_PAGES_STAT_CHUNK_NR)
 			chunk_nr = DO_PAGES_STAT_CHUNK_NR;
 
-		if (copy_from_user(chunk_pages, pages, chunk_nr * sizeof(*chunk_pages)))
+		if (in_compat_syscall()) {
+			if (get_compat_pages_array(chunk_pages, pages,
+						   chunk_nr))
+				break;
+		} else {
+			if (copy_from_user(chunk_pages, pages,
+				      chunk_nr * sizeof(*chunk_pages)))
 				break;
+		}
 
 		do_pages_stat_array(mm, chunk_nr, chunk_pages, chunk_status);
 
@@ -2023,28 +2047,6 @@ SYSCALL_DEFINE6(move_pages, pid_t, pid, unsigned long, nr_pages,
 	return kernel_move_pages(pid, nr_pages, pages, nodes, status, flags);
 }
 
-#ifdef CONFIG_COMPAT
-COMPAT_SYSCALL_DEFINE6(move_pages, pid_t, pid, compat_ulong_t, nr_pages,
-		       compat_uptr_t __user *, pages32,
-		       const int __user *, nodes,
-		       int __user *, status,
-		       int, flags)
-{
-	const void __user * __user *pages;
-	int i;
-
-	pages = compat_alloc_user_space(nr_pages * sizeof(void *));
-	for (i = 0; i < nr_pages; i++) {
-		compat_uptr_t p;
-
-		if (get_user(p, pages32 + i) ||
-			put_user(compat_ptr(p), pages + i))
-			return -EFAULT;
-	}
-	return kernel_move_pages(pid, nr_pages, pages, nodes, status, flags);
-}
-#endif /* CONFIG_COMPAT */
-
 #ifdef CONFIG_NUMA_BALANCING
 /*
  * Returns true if this is a safe migration target node for misplaced NUMA
@@ -2107,6 +2109,7 @@ static struct page *alloc_misplaced_dst_page_thp(struct page *page,
 static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
 {
 	int page_lru;
+	int nr_pages = thp_nr_pages(page);
 
 	VM_BUG_ON_PAGE(compound_order(page) && !PageTransHuge(page), page);
 
@@ -2115,7 +2118,7 @@ static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
 		return 0;
 
 	/* Avoid migrating to a node that is nearly full */
-	if (!migrate_balanced_pgdat(pgdat, compound_nr(page)))
+	if (!migrate_balanced_pgdat(pgdat, nr_pages))
 		return 0;
 
 	if (isolate_lru_page(page))
@@ -2123,7 +2126,7 @@ static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
 
 	page_lru = page_is_file_lru(page);
 	mod_node_page_state(page_pgdat(page), NR_ISOLATED_ANON + page_lru,
-				thp_nr_pages(page));
+			    nr_pages);
 
 	/*
 	 * Isolating the page has taken another reference, so the

mm/page_alloc.c

@@ -3428,8 +3428,10 @@ void free_unref_page_list(struct list_head *list)
 	/* Prepare pages for freeing */
 	list_for_each_entry_safe(page, next, list, lru) {
 		pfn = page_to_pfn(page);
-		if (!free_unref_page_prepare(page, pfn, 0))
+		if (!free_unref_page_prepare(page, pfn, 0)) {
 			list_del(&page->lru);
+			continue;
+		}
 
 		/*
 		 * Free isolated pages directly to the allocator, see

mm/vmscan.c

@@ -2715,7 +2715,7 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc,
 			cgroup_size = max(cgroup_size, protection);
 
 			scan = lruvec_size - lruvec_size * protection /
-				cgroup_size;
+				(cgroup_size + 1);
 
 			/*
 			 * Minimally target SWAP_CLUSTER_MAX pages to keep

mm/vmstat.c

@@ -319,6 +319,16 @@ void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
 	long x;
 	long t;
 
+	/*
+	 * Accurate vmstat updates require a RMW. On !PREEMPT_RT kernels,
+	 * atomicity is provided by IRQs being disabled -- either explicitly
+	 * or via local_lock_irq. On PREEMPT_RT, local_lock_irq only disables
+	 * CPU migrations and preemption potentially corrupts a counter so
+	 * disable preemption.
+	 */
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_disable();
+
 	x = delta + __this_cpu_read(*p);
 
 	t = __this_cpu_read(pcp->stat_threshold);
@@ -328,6 +338,9 @@ void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
 		x = 0;
 	}
 	__this_cpu_write(*p, x);
+
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_enable();
 }
 EXPORT_SYMBOL(__mod_zone_page_state);
 
@@ -350,6 +363,10 @@ void __mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
 		delta >>= PAGE_SHIFT;
 	}
 
+	/* See __mod_node_page_state */
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_disable();
+
 	x = delta + __this_cpu_read(*p);
 
 	t = __this_cpu_read(pcp->stat_threshold);
@@ -359,6 +376,9 @@ void __mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
 		x = 0;
 	}
 	__this_cpu_write(*p, x);
+
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_enable();
 }
 EXPORT_SYMBOL(__mod_node_page_state);
 
@@ -391,6 +411,10 @@ void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
 	s8 __percpu *p = pcp->vm_stat_diff + item;
 	s8 v, t;
 
+	/* See __mod_node_page_state */
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_disable();
+
 	v = __this_cpu_inc_return(*p);
 	t = __this_cpu_read(pcp->stat_threshold);
 	if (unlikely(v > t)) {
@@ -399,6 +423,9 @@ void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
 		zone_page_state_add(v + overstep, zone, item);
 		__this_cpu_write(*p, -overstep);
 	}
+
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_enable();
 }
 
 void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
@@ -409,6 +436,10 @@ void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
 
 	VM_WARN_ON_ONCE(vmstat_item_in_bytes(item));
 
+	/* See __mod_node_page_state */
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_disable();
+
 	v = __this_cpu_inc_return(*p);
 	t = __this_cpu_read(pcp->stat_threshold);
 	if (unlikely(v > t)) {
@@ -417,6 +448,9 @@ void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
 		node_page_state_add(v + overstep, pgdat, item);
 		__this_cpu_write(*p, -overstep);
 	}
+
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_enable();
 }
 
 void __inc_zone_page_state(struct page *page, enum zone_stat_item item)
@@ -437,6 +471,10 @@ void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
 	s8 __percpu *p = pcp->vm_stat_diff + item;
 	s8 v, t;
 
+	/* See __mod_node_page_state */
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_disable();
+
 	v = __this_cpu_dec_return(*p);
 	t = __this_cpu_read(pcp->stat_threshold);
 	if (unlikely(v < - t)) {
@@ -445,6 +483,9 @@ void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
 		zone_page_state_add(v - overstep, zone, item);
 		__this_cpu_write(*p, overstep);
 	}
+
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_enable();
 }
 
 void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
@@ -455,6 +496,10 @@ void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
 
 	VM_WARN_ON_ONCE(vmstat_item_in_bytes(item));
 
+	/* See __mod_node_page_state */
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_disable();
+
 	v = __this_cpu_dec_return(*p);
 	t = __this_cpu_read(pcp->stat_threshold);
 	if (unlikely(v < - t)) {
@@ -463,6 +508,9 @@ void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
 		node_page_state_add(v - overstep, pgdat, item);
 		__this_cpu_write(*p, overstep);
 	}
+
+	if (IS_ENABLED(CONFIG_PREEMPT_RT))
+		preempt_enable();
 }
 
 void __dec_zone_page_state(struct page *page, enum zone_stat_item item)