Merge branch 'akpm' (Andrew's patch-bomb)

Merge misc patches from Andrew Morton:

 - the "misc" tree - stuff from all over the map

 - checkpatch updates

 - fatfs

 - kmod changes

 - procfs

 - cpumask

 - UML

 - kexec

 - mqueue

 - rapidio

 - pidns

 - some checkpoint-restore feature work.  Reluctantly.  Most of it
   delayed a release.  I'm still rather worried that we don't have a
   clear roadmap to completion for this work.

* emailed from Andrew Morton <akpm@linux-foundation.org>: (78 patches)
  kconfig: update compression algorithm info
  c/r: prctl: add ability to set new mm_struct::exe_file
  c/r: prctl: extend PR_SET_MM to set up more mm_struct entries
  c/r: procfs: add arg_start/end, env_start/end and exit_code members to /proc/$pid/stat
  syscalls, x86: add __NR_kcmp syscall
  fs, proc: introduce /proc/<pid>/task/<tid>/children entry
  sysctl: make kernel.ns_last_pid control dependent on CHECKPOINT_RESTORE
  aio/vfs: cleanup of rw_copy_check_uvector() and compat_rw_copy_check_uvector()
  eventfd: change int to __u64 in eventfd_signal()
  fs/nls: add Apple NLS
  pidns: make killed children autoreap
  pidns: use task_active_pid_ns in do_notify_parent
  rapidio/tsi721: add DMA engine support
  rapidio: add DMA engine support for RIO data transfers
  ipc/mqueue: add rbtree node caching support
  tools/selftests: add mq_perf_tests
  ipc/mqueue: strengthen checks on mqueue creation
  ipc/mqueue: correct mq_attr_ok test
  ipc/mqueue: improve performance of send/recv
  selftests: add mq_open_tests
  ...

18 files changed, 206 insertions, 73 deletions

diff --git a/include/linux/Kbuild b/include/linux/Kbuild
index 7185b8f15ced..8760be30b375 100644
--- a/include/linux/Kbuild
+++ b/include/linux/Kbuild
@@ -226,6 +226,7 @@ header-y += kdev_t.h
 header-y += kernel.h
 header-y += kernelcapi.h
 header-y += kernel-page-flags.h
+header-y += kexec.h
 header-y += keyboard.h
 header-y += keyctl.h
 header-y += l2tp.h
diff --git a/include/linux/compat.h b/include/linux/compat.h
index 5d46217f84ad..4e890394ef99 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -577,8 +577,7 @@ extern ssize_t compat_rw_copy_check_uvector(int type,
 		const struct compat_iovec __user *uvector,
 		unsigned long nr_segs,
 		unsigned long fast_segs, struct iovec *fast_pointer,
-		struct iovec **ret_pointer,
-		int check_access);
+		struct iovec **ret_pointer);
 
 extern void __user *compat_alloc_user_space(unsigned long len);
 
diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index 7230bb59a06f..2e9b9ebbeb78 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -177,6 +177,7 @@ extern void put_online_cpus(void);
 #define hotcpu_notifier(fn, pri)	cpu_notifier(fn, pri)
 #define register_hotcpu_notifier(nb)	register_cpu_notifier(nb)
 #define unregister_hotcpu_notifier(nb)	unregister_cpu_notifier(nb)
+void clear_tasks_mm_cpumask(int cpu);
 int cpu_down(unsigned int cpu);
 
 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
diff --git a/include/linux/cred.h b/include/linux/cred.h
index 917dc5aeb1d4..ebbed2ce6637 100644
--- a/include/linux/cred.h
+++ b/include/linux/cred.h
@@ -277,17 +277,13 @@ static inline void put_cred(const struct cred *_cred)
  * @task: The task to query
  *
  * Access the objective credentials of a task.  The caller must hold the RCU
- * readlock or the task must be dead and unable to change its own credentials.
+ * readlock.
  *
  * The result of this function should not be passed directly to get_cred();
  * rather get_task_cred() should be used instead.
  */
-#define __task_cred(task)						\
-	({								\
-		const struct task_struct *__t = (task);			\
-		rcu_dereference_check(__t->real_cred,			\
-				      task_is_dead(__t));		\
-	})
+#define __task_cred(task)	\
+	rcu_dereference((task)->real_cred)
 
 /**
  * get_current_cred - Get the current task's subjective credentials
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index d3fec584e8c3..56377df39124 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -635,6 +635,18 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_slave_sg(
 						  dir, flags, NULL);
 }
 
+#ifdef CONFIG_RAPIDIO_DMA_ENGINE
+struct rio_dma_ext;
+static inline struct dma_async_tx_descriptor *dmaengine_prep_rio_sg(
+	struct dma_chan *chan, struct scatterlist *sgl,	unsigned int sg_len,
+	enum dma_transfer_direction dir, unsigned long flags,
+	struct rio_dma_ext *rio_ext)
+{
+	return chan->device->device_prep_slave_sg(chan, sgl, sg_len,
+						  dir, flags, rio_ext);
+}
+#endif
+
 static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_cyclic(
 		struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
 		size_t period_len, enum dma_transfer_direction dir)
diff --git a/include/linux/eventfd.h b/include/linux/eventfd.h
index 91bb4f27238c..3c3ef19a625a 100644
--- a/include/linux/eventfd.h
+++ b/include/linux/eventfd.h
@@ -34,7 +34,7 @@ void eventfd_ctx_put(struct eventfd_ctx *ctx);
 struct file *eventfd_fget(int fd);
 struct eventfd_ctx *eventfd_ctx_fdget(int fd);
 struct eventfd_ctx *eventfd_ctx_fileget(struct file *file);
-int eventfd_signal(struct eventfd_ctx *ctx, int n);
+__u64 eventfd_signal(struct eventfd_ctx *ctx, __u64 n);
 ssize_t eventfd_ctx_read(struct eventfd_ctx *ctx, int no_wait, __u64 *cnt);
 int eventfd_ctx_remove_wait_queue(struct eventfd_ctx *ctx, wait_queue_t *wait,
 				  __u64 *cnt);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 598a5892ff2b..40887afaaca7 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -173,6 +173,15 @@ struct inodes_stat_t {
 #define WRITE_FUA		(WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FUA)
 #define WRITE_FLUSH_FUA		(WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH | REQ_FUA)
 
+
+/*
+ * Flag for rw_copy_check_uvector and compat_rw_copy_check_uvector
+ * that indicates that they should check the contents of the iovec are
+ * valid, but not check the memory that the iovec elements
+ * points too.
+ */
+#define CHECK_IOVEC_ONLY -1
+
 #define SEL_IN		1
 #define SEL_OUT		2
 #define SEL_EX		4
@@ -1690,8 +1699,7 @@ struct seq_file;
 ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
 			      unsigned long nr_segs, unsigned long fast_segs,
 			      struct iovec *fast_pointer,
-			      struct iovec **ret_pointer,
-			      int check_access);
+			      struct iovec **ret_pointer);
 
 extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
 extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
diff --git a/include/linux/ipc_namespace.h b/include/linux/ipc_namespace.h
index 8a297a5e794c..5499c92a9153 100644
--- a/include/linux/ipc_namespace.h
+++ b/include/linux/ipc_namespace.h
@@ -62,6 +62,8 @@ struct ipc_namespace {
 	unsigned int    mq_queues_max;   /* initialized to DFLT_QUEUESMAX */
 	unsigned int    mq_msg_max;      /* initialized to DFLT_MSGMAX */
 	unsigned int    mq_msgsize_max;  /* initialized to DFLT_MSGSIZEMAX */
+	unsigned int    mq_msg_default;
+	unsigned int    mq_msgsize_default;
 
 	/* user_ns which owns the ipc ns */
 	struct user_namespace *user_ns;
@@ -90,11 +92,41 @@ static inline void shm_destroy_orphaned(struct ipc_namespace *ns) {}
 
 #ifdef CONFIG_POSIX_MQUEUE
 extern int mq_init_ns(struct ipc_namespace *ns);
-/* default values */
-#define DFLT_QUEUESMAX 256     /* max number of message queues */
-#define DFLT_MSGMAX    10      /* max number of messages in each queue */
-#define HARD_MSGMAX    (32768*sizeof(void *)/4)
-#define DFLT_MSGSIZEMAX 8192   /* max message size */
+/*
+ * POSIX Message Queue default values:
+ *
+ * MIN_*: Lowest value an admin can set the maximum unprivileged limit to
+ * DFLT_*MAX: Default values for the maximum unprivileged limits
+ * DFLT_{MSG,MSGSIZE}: Default values used when the user doesn't supply
+ *   an attribute to the open call and the queue must be created
+ * HARD_*: Highest value the maximums can be set to.  These are enforced
+ *   on CAP_SYS_RESOURCE apps as well making them inviolate (so make them
+ *   suitably high)
+ *
+ * POSIX Requirements:
+ *   Per app minimum openable message queues - 8.  This does not map well
+ *     to the fact that we limit the number of queues on a per namespace
+ *     basis instead of a per app basis.  So, make the default high enough
+ *     that no given app should have a hard time opening 8 queues.
+ *   Minimum maximum for HARD_MSGMAX - 32767.  I bumped this to 65536.
+ *   Minimum maximum for HARD_MSGSIZEMAX - POSIX is silent on this.  However,
+ *     we have run into a situation where running applications in the wild
+ *     require this to be at least 5MB, and preferably 10MB, so I set the
+ *     value to 16MB in hopes that this user is the worst of the bunch and
+ *     the new maximum will handle anyone else.  I may have to revisit this
+ *     in the future.
+ */
+#define MIN_QUEUESMAX			1
+#define DFLT_QUEUESMAX		      256
+#define HARD_QUEUESMAX		     1024
+#define MIN_MSGMAX			1
+#define DFLT_MSG		       10U
+#define DFLT_MSGMAX		       10
+#define HARD_MSGMAX		    65536
+#define MIN_MSGSIZEMAX		      128
+#define DFLT_MSGSIZE		     8192U
+#define DFLT_MSGSIZEMAX		     8192
+#define HARD_MSGSIZEMAX	    (16*1024*1024)
 #else
 static inline int mq_init_ns(struct ipc_namespace *ns) { return 0; }
 #endif
diff --git a/include/linux/kcmp.h b/include/linux/kcmp.h
new file mode 100644
index 000000000000..2dcd1b3aafc8
--- /dev/null
+++ b/include/linux/kcmp.h
@@ -0,0 +1,17 @@
+#ifndef _LINUX_KCMP_H
+#define _LINUX_KCMP_H
+
+/* Comparison type */
+enum kcmp_type {
+	KCMP_FILE,
+	KCMP_VM,
+	KCMP_FILES,
+	KCMP_FS,
+	KCMP_SIGHAND,
+	KCMP_IO,
+	KCMP_SYSVSEM,
+
+	KCMP_TYPES,
+};
+
+#endif /* _LINUX_KCMP_H */
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index ec55a3c8ba77..e07f5e0c5df4 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -35,6 +35,7 @@
 #define LLONG_MAX	((long long)(~0ULL>>1))
 #define LLONG_MIN	(-LLONG_MAX - 1)
 #define ULLONG_MAX	(~0ULL)
+#define SIZE_MAX	(~(size_t)0)
 
 #define STACK_MAGIC	0xdeadbeef
 
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 0d7d6a1b172f..37c5f7261142 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -1,8 +1,58 @@
 #ifndef LINUX_KEXEC_H
 #define LINUX_KEXEC_H
 
-#ifdef CONFIG_KEXEC
+/* kexec system call -  It loads the new kernel to boot into.
+ * kexec does not sync, or unmount filesystems so if you need
+ * that to happen you need to do that yourself.
+ */
+
 #include <linux/types.h>
+
+/* kexec flags for different usage scenarios */
+#define KEXEC_ON_CRASH		0x00000001
+#define KEXEC_PRESERVE_CONTEXT	0x00000002
+#define KEXEC_ARCH_MASK		0xffff0000
+
+/* These values match the ELF architecture values.
+ * Unless there is a good reason that should continue to be the case.
+ */
+#define KEXEC_ARCH_DEFAULT ( 0 << 16)
+#define KEXEC_ARCH_386     ( 3 << 16)
+#define KEXEC_ARCH_X86_64  (62 << 16)
+#define KEXEC_ARCH_PPC     (20 << 16)
+#define KEXEC_ARCH_PPC64   (21 << 16)
+#define KEXEC_ARCH_IA_64   (50 << 16)
+#define KEXEC_ARCH_ARM     (40 << 16)
+#define KEXEC_ARCH_S390    (22 << 16)
+#define KEXEC_ARCH_SH      (42 << 16)
+#define KEXEC_ARCH_MIPS_LE (10 << 16)
+#define KEXEC_ARCH_MIPS    ( 8 << 16)
+
+/* The artificial cap on the number of segments passed to kexec_load. */
+#define KEXEC_SEGMENT_MAX 16
+
+#ifndef __KERNEL__
+/*
+ * This structure is used to hold the arguments that are used when
+ * loading  kernel binaries.
+ */
+struct kexec_segment {
+	const void *buf;
+	size_t bufsz;
+	const void *mem;
+	size_t memsz;
+};
+
+/* Load a new kernel image as described by the kexec_segment array
+ * consisting of passed number of segments at the entry-point address.
+ * The flags allow different useage types.
+ */
+extern int kexec_load(void *, size_t, struct kexec_segment *,
+		unsigned long int);
+#endif /* __KERNEL__ */
+
+#ifdef __KERNEL__
+#ifdef CONFIG_KEXEC
 #include <linux/list.h>
 #include <linux/linkage.h>
 #include <linux/compat.h>
@@ -67,11 +117,10 @@ typedef unsigned long kimage_entry_t;
 #define IND_DONE         0x4
 #define IND_SOURCE       0x8
 
-#define KEXEC_SEGMENT_MAX 16
 struct kexec_segment {
 	void __user *buf;
 	size_t bufsz;
-	unsigned long mem;	/* User space sees this as a (void *) ... */
+	unsigned long mem;
 	size_t memsz;
 };
 
@@ -175,25 +224,6 @@ extern struct kimage *kexec_crash_image;
 #define kexec_flush_icache_page(page)
 #endif
 
-#define KEXEC_ON_CRASH		0x00000001
-#define KEXEC_PRESERVE_CONTEXT	0x00000002
-#define KEXEC_ARCH_MASK		0xffff0000
-
-/* These values match the ELF architecture values.
- * Unless there is a good reason that should continue to be the case.
- */
-#define KEXEC_ARCH_DEFAULT ( 0 << 16)
-#define KEXEC_ARCH_386     ( 3 << 16)
-#define KEXEC_ARCH_X86_64  (62 << 16)
-#define KEXEC_ARCH_PPC     (20 << 16)
-#define KEXEC_ARCH_PPC64   (21 << 16)
-#define KEXEC_ARCH_IA_64   (50 << 16)
-#define KEXEC_ARCH_ARM     (40 << 16)
-#define KEXEC_ARCH_S390    (22 << 16)
-#define KEXEC_ARCH_SH      (42 << 16)
-#define KEXEC_ARCH_MIPS_LE (10 << 16)
-#define KEXEC_ARCH_MIPS    ( 8 << 16)
-
 /* List of defined/legal kexec flags */
 #ifndef CONFIG_KEXEC_JUMP
 #define KEXEC_FLAGS    KEXEC_ON_CRASH
@@ -228,4 +258,5 @@ struct task_struct;
 static inline void crash_kexec(struct pt_regs *regs) { }
 static inline int kexec_should_crash(struct task_struct *p) { return 0; }
 #endif /* CONFIG_KEXEC */
+#endif /* __KERNEL__ */
 #endif /* LINUX_KEXEC_H */
diff --git a/include/linux/kmod.h b/include/linux/kmod.h
index dd99c329e161..5398d5807075 100644
--- a/include/linux/kmod.h
+++ b/include/linux/kmod.h
@@ -66,40 +66,10 @@ struct subprocess_info {
 	void *data;
 };
 
-/* Allocate a subprocess_info structure */
-struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
-						  char **envp, gfp_t gfp_mask);
-
-/* Set various pieces of state into the subprocess_info structure */
-void call_usermodehelper_setfns(struct subprocess_info *info,
-		    int (*init)(struct subprocess_info *info, struct cred *new),
-		    void (*cleanup)(struct subprocess_info *info),
-		    void *data);
-
-/* Actually execute the sub-process */
-int call_usermodehelper_exec(struct subprocess_info *info, int wait);
-
-/* Free the subprocess_info. This is only needed if you're not going
-   to call call_usermodehelper_exec */
-void call_usermodehelper_freeinfo(struct subprocess_info *info);
-
-static inline int
+extern int
 call_usermodehelper_fns(char *path, char **argv, char **envp, int wait,
 			int (*init)(struct subprocess_info *info, struct cred *new),
-			void (*cleanup)(struct subprocess_info *), void *data)
-{
-	struct subprocess_info *info;
-	gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
-
-	info = call_usermodehelper_setup(path, argv, envp, gfp_mask);
-
-	if (info == NULL)
-		return -ENOMEM;
-
-	call_usermodehelper_setfns(info, init, cleanup, data);
-
-	return call_usermodehelper_exec(info, wait);
-}
+			void (*cleanup)(struct subprocess_info *), void *data);
 
 static inline int
 call_usermodehelper(char *path, char **argv, char **envp, int wait)
diff --git a/include/linux/msdos_fs.h b/include/linux/msdos_fs.h
index 34066e65fdeb..11cc2ac67e75 100644
--- a/include/linux/msdos_fs.h
+++ b/include/linux/msdos_fs.h
@@ -21,8 +21,9 @@
 #define CT_LE_W(v)	cpu_to_le16(v)
 #define CT_LE_L(v)	cpu_to_le32(v)
 
+#define MSDOS_ROOT_INO	 1	/* The root inode number */
+#define MSDOS_FSINFO_INO 2	/* Used for managing the FSINFO block */
 
-#define MSDOS_ROOT_INO	1	/* == MINIX_ROOT_INO */
 #define MSDOS_DIR_BITS	5	/* log2(sizeof(struct msdos_dir_entry)) */
 
 /* directory limit */
diff --git a/include/linux/prctl.h b/include/linux/prctl.h
index 78b76e24cc7e..711e0a30aacc 100644
--- a/include/linux/prctl.h
+++ b/include/linux/prctl.h
@@ -113,6 +113,12 @@
 # define PR_SET_MM_START_STACK		5
 # define PR_SET_MM_START_BRK		6
 # define PR_SET_MM_BRK			7
+# define PR_SET_MM_ARG_START		8
+# define PR_SET_MM_ARG_END		9
+# define PR_SET_MM_ENV_START		10
+# define PR_SET_MM_ENV_END		11
+# define PR_SET_MM_AUXV			12
+# define PR_SET_MM_EXE_FILE		13
 
 /*
  * Set specific pid that is allowed to ptrace the current task.
diff --git a/include/linux/rio.h b/include/linux/rio.h
index 4d50611112ba..a90ebadd9da0 100644
--- a/include/linux/rio.h
+++ b/include/linux/rio.h
@@ -20,6 +20,9 @@
 #include <linux/errno.h>
 #include <linux/device.h>
 #include <linux/rio_regs.h>
+#ifdef CONFIG_RAPIDIO_DMA_ENGINE
+#include <linux/dmaengine.h>
+#endif
 
 #define RIO_NO_HOPCOUNT		-1
 #define RIO_INVALID_DESTID	0xffff
@@ -254,6 +257,9 @@ struct rio_mport {
 	u32 phys_efptr;
 	unsigned char name[40];
 	void *priv;		/* Master port private data */
+#ifdef CONFIG_RAPIDIO_DMA_ENGINE
+	struct dma_device	dma;
+#endif
 };
 
 /**
@@ -395,6 +401,47 @@ union rio_pw_msg {
 	u32 raw[RIO_PW_MSG_SIZE/sizeof(u32)];
 };
 
+#ifdef CONFIG_RAPIDIO_DMA_ENGINE
+
+/**
+ * enum rio_write_type - RIO write transaction types used in DMA transfers
+ *
+ * Note: RapidIO specification defines write (NWRITE) and
+ * write-with-response (NWRITE_R) data transfer operations.
+ * Existing DMA controllers that service RapidIO may use one of these operations
+ * for entire data transfer or their combination with only the last data packet
+ * requires response.
+ */
+enum rio_write_type {
+	RDW_DEFAULT,		/* default method used by DMA driver */
+	RDW_ALL_NWRITE,		/* all packets use NWRITE */
+	RDW_ALL_NWRITE_R,	/* all packets use NWRITE_R */
+	RDW_LAST_NWRITE_R,	/* last packet uses NWRITE_R, others - NWRITE */
+};
+
+struct rio_dma_ext {
+	u16 destid;
+	u64 rio_addr;	/* low 64-bits of 66-bit RapidIO address */
+	u8  rio_addr_u;  /* upper 2-bits of 66-bit RapidIO address */
+	enum rio_write_type wr_type; /* preferred RIO write operation type */
+};
+
+struct rio_dma_data {
+	/* Local data (as scatterlist) */
+	struct scatterlist	*sg;	/* I/O scatter list */
+	unsigned int		sg_len;	/* size of scatter list */
+	/* Remote device address (flat buffer) */
+	u64 rio_addr;	/* low 64-bits of 66-bit RapidIO address */
+	u8  rio_addr_u;  /* upper 2-bits of 66-bit RapidIO address */
+	enum rio_write_type wr_type; /* preferred RIO write operation type */
+};
+
+static inline struct rio_mport *dma_to_mport(struct dma_device *ddev)
+{
+	return container_of(ddev, struct rio_mport, dma);
+}
+#endif /* CONFIG_RAPIDIO_DMA_ENGINE */
+
 /* Architecture and hardware-specific functions */
 extern int rio_register_mport(struct rio_mport *);
 extern int rio_open_inb_mbox(struct rio_mport *, void *, int, int);
diff --git a/include/linux/rio_drv.h b/include/linux/rio_drv.h
index 7f07470e1ed9..31ad146be316 100644
--- a/include/linux/rio_drv.h
+++ b/include/linux/rio_drv.h
@@ -377,6 +377,15 @@ void rio_unregister_driver(struct rio_driver *);
 struct rio_dev *rio_dev_get(struct rio_dev *);
 void rio_dev_put(struct rio_dev *);
 
+#ifdef CONFIG_RAPIDIO_DMA_ENGINE
+extern struct dma_chan *rio_request_dma(struct rio_dev *rdev);
+extern void rio_release_dma(struct dma_chan *dchan);
+extern struct dma_async_tx_descriptor *rio_dma_prep_slave_sg(
+		struct rio_dev *rdev, struct dma_chan *dchan,
+		struct rio_dma_data *data,
+		enum dma_transfer_direction direction, unsigned long flags);
+#endif
+
 /**
  * rio_name - Get the unique RIO device identifier
  * @rdev: RIO device
diff --git a/include/linux/slab.h b/include/linux/slab.h
index a595dce6b0c7..67d5d94b783a 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -242,7 +242,7 @@ size_t ksize(const void *);
  */
 static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags)
 {
-	if (size != 0 && n > ULONG_MAX / size)
+	if (size != 0 && n > SIZE_MAX / size)
 		return NULL;
 	return __kmalloc(n * size, flags);
 }
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 3de3acb84a95..19439c75c5b2 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -858,4 +858,6 @@ asmlinkage long sys_process_vm_writev(pid_t pid,
 				      unsigned long riovcnt,
 				      unsigned long flags);
 
+asmlinkage long sys_kcmp(pid_t pid1, pid_t pid2, int type,
+			 unsigned long idx1, unsigned long idx2);
 #endif