Merge branch 'akpm' (incoming from Andrew)

Merge third batch of fixes from Andrew Morton:
 "Most of the rest.  I still have two large patchsets against AIO and
  IPC, but they're a bit stuck behind other trees and I'm about to
  vanish for six days.

   - random fixlets
   - inotify
   - more of the MM queue
   - show_stack() cleanups
   - DMI update
   - kthread/workqueue things
   - compat cleanups
   - epoll udpates
   - binfmt updates
   - nilfs2
   - hfs
   - hfsplus
   - ptrace
   - kmod
   - coredump
   - kexec
   - rbtree
   - pids
   - pidns
   - pps
   - semaphore tweaks
   - some w1 patches
   - relay updates
   - core Kconfig changes
   - sysrq tweaks"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (109 commits)
  Documentation/sysrq: fix inconstistent help message of sysrq key
  ethernet/emac/sysrq: fix inconstistent help message of sysrq key
  sparc/sysrq: fix inconstistent help message of sysrq key
  powerpc/xmon/sysrq: fix inconstistent help message of sysrq key
  ARM/etm/sysrq: fix inconstistent help message of sysrq key
  power/sysrq: fix inconstistent help message of sysrq key
  kgdb/sysrq: fix inconstistent help message of sysrq key
  lib/decompress.c: fix initconst
  notifier-error-inject: fix module names in Kconfig
  kernel/sys.c: make prctl(PR_SET_MM) generally available
  UAPI: remove empty Kbuild files
  menuconfig: print more info for symbol without prompts
  init/Kconfig: re-order CONFIG_EXPERT options to fix menuconfig display
  kconfig menu: move Virtualization drivers near other virtualization options
  Kconfig: consolidate CONFIG_DEBUG_STRICT_USER_COPY_CHECKS
  relay: use macro PAGE_ALIGN instead of FIX_SIZE
  kernel/relay.c: move FIX_SIZE macro into relay.c
  kernel/relay.c: remove unused function argument actor
  drivers/w1/slaves/w1_ds2760.c: fix the error handling in w1_ds2760_add_slave()
  drivers/w1/slaves/w1_ds2781.c: fix the error handling in w1_ds2781_add_slave()
  ...

5 files changed, 353 insertions, 3 deletions

diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index 3cc0ad7ae86..fa6ea69f2e4 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -1,10 +1,12 @@
 TARGETS = breakpoints
+TARGETS += cpu-hotplug
+TARGETS += efivarfs
 TARGETS += kcmp
+TARGETS += memory-hotplug
 TARGETS += mqueue
+TARGETS += ptrace
+TARGETS += soft-dirty
 TARGETS += vm
-TARGETS += cpu-hotplug
-TARGETS += memory-hotplug
-TARGETS += efivarfs
 
 all:
 	for TARGET in $(TARGETS); do \
diff --git a/tools/testing/selftests/ptrace/Makefile b/tools/testing/selftests/ptrace/Makefile
new file mode 100644
index 00000000000..47ae2d385ce
--- /dev/null
+++ b/tools/testing/selftests/ptrace/Makefile
@@ -0,0 +1,10 @@
+CFLAGS += -iquote../../../../include/uapi -Wall
+peeksiginfo: peeksiginfo.c
+
+all: peeksiginfo
+
+clean:
+	rm -f peeksiginfo
+
+run_tests: all
+	@./peeksiginfo || echo "peeksiginfo selftests: [FAIL]"
diff --git a/tools/testing/selftests/ptrace/peeksiginfo.c b/tools/testing/selftests/ptrace/peeksiginfo.c
new file mode 100644
index 00000000000..d46558b1f58
--- /dev/null
+++ b/tools/testing/selftests/ptrace/peeksiginfo.c
@@ -0,0 +1,214 @@
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <signal.h>
+#include <unistd.h>
+#include <errno.h>
+#include <linux/types.h>
+#include <sys/wait.h>
+#include <sys/syscall.h>
+#include <sys/user.h>
+#include <sys/mman.h>
+
+#include "linux/ptrace.h"
+
+static int sys_rt_sigqueueinfo(pid_t tgid, int sig, siginfo_t *uinfo)
+{
+	return syscall(SYS_rt_sigqueueinfo, tgid, sig, uinfo);
+}
+
+static int sys_rt_tgsigqueueinfo(pid_t tgid, pid_t tid,
+					int sig, siginfo_t *uinfo)
+{
+	return syscall(SYS_rt_tgsigqueueinfo, tgid, tid, sig, uinfo);
+}
+
+static int sys_ptrace(int request, pid_t pid, void *addr, void *data)
+{
+	return syscall(SYS_ptrace, request, pid, addr, data);
+}
+
+#define SIGNR 10
+#define TEST_SICODE_PRIV	-1
+#define TEST_SICODE_SHARE	-2
+
+#define err(fmt, ...)						\
+		fprintf(stderr,					\
+			"Error (%s:%d): " fmt,			\
+			__FILE__, __LINE__, ##__VA_ARGS__)
+
+static int check_error_paths(pid_t child)
+{
+	struct ptrace_peeksiginfo_args arg;
+	int ret, exit_code = -1;
+	void *addr_rw, *addr_ro;
+
+	/*
+	 * Allocate two contiguous pages. The first one is for read-write,
+	 * another is for read-only.
+	 */
+	addr_rw = mmap(NULL, 2 * PAGE_SIZE, PROT_READ | PROT_WRITE,
+				MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+	if (addr_rw == MAP_FAILED) {
+		err("mmap() failed: %m\n");
+		return 1;
+	}
+
+	addr_ro = mmap(addr_rw + PAGE_SIZE, PAGE_SIZE, PROT_READ,
+			MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
+	if (addr_ro == MAP_FAILED) {
+		err("mmap() failed: %m\n");
+		goto out;
+	}
+
+	arg.nr = SIGNR;
+	arg.off = 0;
+
+	/* Unsupported flags */
+	arg.flags = ~0;
+	ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, addr_rw);
+	if (ret != -1 || errno != EINVAL) {
+		err("sys_ptrace() returns %d (expected -1),"
+				" errno %d (expected %d): %m\n",
+				ret, errno, EINVAL);
+		goto out;
+	}
+	arg.flags = 0;
+
+	/* A part of the buffer is read-only */
+	ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg,
+					addr_ro - sizeof(siginfo_t) * 2);
+	if (ret != 2) {
+		err("sys_ptrace() returns %d (expected 2): %m\n", ret);
+		goto out;
+	}
+
+	/* Read-only buffer */
+	ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, addr_ro);
+	if (ret != -1 && errno != EFAULT) {
+		err("sys_ptrace() returns %d (expected -1),"
+				" errno %d (expected %d): %m\n",
+				ret, errno, EFAULT);
+		goto out;
+	}
+
+	exit_code = 0;
+out:
+	munmap(addr_rw, 2 * PAGE_SIZE);
+	return exit_code;
+}
+
+int check_direct_path(pid_t child, int shared, int nr)
+{
+	struct ptrace_peeksiginfo_args arg = {.flags = 0, .nr = nr, .off = 0};
+	int i, j, ret, exit_code = -1;
+	siginfo_t siginfo[SIGNR];
+	int si_code;
+
+	if (shared == 1) {
+		arg.flags = PTRACE_PEEKSIGINFO_SHARED;
+		si_code = TEST_SICODE_SHARE;
+	} else {
+		arg.flags = 0;
+		si_code = TEST_SICODE_PRIV;
+	}
+
+	for (i = 0; i < SIGNR; ) {
+		arg.off = i;
+		ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, siginfo);
+		if (ret == -1) {
+			err("ptrace() failed: %m\n");
+			goto out;
+		}
+
+		if (ret == 0)
+			break;
+
+		for (j = 0; j < ret; j++, i++) {
+			if (siginfo[j].si_code == si_code &&
+			    siginfo[j].si_int == i)
+				continue;
+
+			err("%d: Wrong siginfo i=%d si_code=%d si_int=%d\n",
+			     shared, i, siginfo[j].si_code, siginfo[j].si_int);
+			goto out;
+		}
+	}
+
+	if (i != SIGNR) {
+		err("Only %d signals were read\n", i);
+		goto out;
+	}
+
+	exit_code = 0;
+out:
+	return exit_code;
+}
+
+int main(int argc, char *argv[])
+{
+	siginfo_t siginfo[SIGNR];
+	int i, exit_code = 1;
+	sigset_t blockmask;
+	pid_t child;
+
+	sigemptyset(&blockmask);
+	sigaddset(&blockmask, SIGRTMIN);
+	sigprocmask(SIG_BLOCK, &blockmask, NULL);
+
+	child = fork();
+	if (child == -1) {
+		err("fork() failed: %m");
+		return 1;
+	} else if (child == 0) {
+		pid_t ppid = getppid();
+		while (1) {
+			if (ppid != getppid())
+				break;
+			sleep(1);
+		}
+		return 1;
+	}
+
+	/* Send signals in process-wide and per-thread queues */
+	for (i = 0; i < SIGNR; i++) {
+		siginfo->si_code = TEST_SICODE_SHARE;
+		siginfo->si_int = i;
+		sys_rt_sigqueueinfo(child, SIGRTMIN, siginfo);
+
+		siginfo->si_code = TEST_SICODE_PRIV;
+		siginfo->si_int = i;
+		sys_rt_tgsigqueueinfo(child, child, SIGRTMIN, siginfo);
+	}
+
+	if (sys_ptrace(PTRACE_ATTACH, child, NULL, NULL) == -1)
+		return 1;
+
+	waitpid(child, NULL, 0);
+
+	/* Dump signals one by one*/
+	if (check_direct_path(child, 0, 1))
+		goto out;
+	/* Dump all signals for one call */
+	if (check_direct_path(child, 0, SIGNR))
+		goto out;
+
+	/*
+	 * Dump signal from the process-wide queue.
+	 * The number of signals is not multible to the buffer size
+	 */
+	if (check_direct_path(child, 1, 3))
+		goto out;
+
+	if (check_error_paths(child))
+		goto out;
+
+	printf("PASS\n");
+	exit_code = 0;
+out:
+	if (sys_ptrace(PTRACE_KILL, child, NULL, NULL) == -1)
+		return 1;
+
+	waitpid(child, NULL, 0);
+
+	return exit_code;
+}
diff --git a/tools/testing/selftests/soft-dirty/Makefile b/tools/testing/selftests/soft-dirty/Makefile
new file mode 100644
index 00000000000..a9cdc823d6e
--- /dev/null
+++ b/tools/testing/selftests/soft-dirty/Makefile
@@ -0,0 +1,10 @@
+CFLAGS += -iquote../../../../include/uapi -Wall
+soft-dirty: soft-dirty.c
+
+all: soft-dirty
+
+clean:
+	rm -f soft-dirty
+
+run_tests: all
+	@./soft-dirty || echo "soft-dirty selftests: [FAIL]"
diff --git a/tools/testing/selftests/soft-dirty/soft-dirty.c b/tools/testing/selftests/soft-dirty/soft-dirty.c
new file mode 100644
index 00000000000..aba4f87f87f
--- /dev/null
+++ b/tools/testing/selftests/soft-dirty/soft-dirty.c
@@ -0,0 +1,114 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/types.h>
+
+typedef unsigned long long u64;
+
+#define PME_PRESENT	(1ULL << 63)
+#define PME_SOFT_DIRTY	(1Ull << 55)
+
+#define PAGES_TO_TEST	3
+#ifndef PAGE_SIZE
+#define PAGE_SIZE	4096
+#endif
+
+static void get_pagemap2(char *mem, u64 *map)
+{
+	int fd;
+
+	fd = open("/proc/self/pagemap2", O_RDONLY);
+	if (fd < 0) {
+		perror("Can't open pagemap2");
+		exit(1);
+	}
+
+	lseek(fd, (unsigned long)mem / PAGE_SIZE * sizeof(u64), SEEK_SET);
+	read(fd, map, sizeof(u64) * PAGES_TO_TEST);
+	close(fd);
+}
+
+static inline char map_p(u64 map)
+{
+	return map & PME_PRESENT ? 'p' : '-';
+}
+
+static inline char map_sd(u64 map)
+{
+	return map & PME_SOFT_DIRTY ? 'd' : '-';
+}
+
+static int check_pte(int step, int page, u64 *map, u64 want)
+{
+	if ((map[page] & want) != want) {
+		printf("Step %d Page %d has %c%c, want %c%c\n",
+				step, page,
+				map_p(map[page]), map_sd(map[page]),
+				map_p(want), map_sd(want));
+		return 1;
+	}
+
+	return 0;
+}
+
+static void clear_refs(void)
+{
+	int fd;
+	char *v = "4";
+
+	fd = open("/proc/self/clear_refs", O_WRONLY);
+	if (write(fd, v, 3) < 3) {
+		perror("Can't clear soft-dirty bit");
+		exit(1);
+	}
+	close(fd);
+}
+
+int main(void)
+{
+	char *mem, x;
+	u64 map[PAGES_TO_TEST];
+
+	mem = mmap(NULL, PAGES_TO_TEST * PAGE_SIZE,
+			PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, 0, 0);
+
+	x = mem[0];
+	mem[2 * PAGE_SIZE] = 'c';
+	get_pagemap2(mem, map);
+
+	if (check_pte(1, 0, map, PME_PRESENT))
+		return 1;
+	if (check_pte(1, 1, map, 0))
+		return 1;
+	if (check_pte(1, 2, map, PME_PRESENT | PME_SOFT_DIRTY))
+		return 1;
+
+	clear_refs();
+	get_pagemap2(mem, map);
+
+	if (check_pte(2, 0, map, PME_PRESENT))
+		return 1;
+	if (check_pte(2, 1, map, 0))
+		return 1;
+	if (check_pte(2, 2, map, PME_PRESENT))
+		return 1;
+
+	mem[0] = 'a';
+	mem[PAGE_SIZE] = 'b';
+	x = mem[2 * PAGE_SIZE];
+	get_pagemap2(mem, map);
+
+	if (check_pte(3, 0, map, PME_PRESENT | PME_SOFT_DIRTY))
+		return 1;
+	if (check_pte(3, 1, map, PME_PRESENT | PME_SOFT_DIRTY))
+		return 1;
+	if (check_pte(3, 2, map, PME_PRESENT))
+		return 1;
+
+	(void)x; /* gcc warn */
+
+	printf("PASS\n");
+	return 0;
+}