Merge branch 'akpm' (patches from Andrew)

Merge more updates from Andrew Morton:
 "VM:
   - z3fold fixes and enhancements by Henry Burns and Vitaly Wool

   - more accurate reclaimed slab caches calculations by Yafang Shao

   - fix MAP_UNINITIALIZED UAPI symbol to not depend on config, by
     Christoph Hellwig

   - !CONFIG_MMU fixes by Christoph Hellwig

   - new novmcoredd parameter to omit device dumps from vmcore, by
     Kairui Song

   - new test_meminit module for testing heap and pagealloc
     initialization, by Alexander Potapenko

   - ioremap improvements for huge mappings, by Anshuman Khandual

   - generalize kprobe page fault handling, by Anshuman Khandual

   - device-dax hotplug fixes and improvements, by Pavel Tatashin

   - enable synchronous DAX fault on powerpc, by Aneesh Kumar K.V

   - add pte_devmap() support for arm64, by Robin Murphy

   - unify locked_vm accounting with a helper, by Daniel Jordan

   - several misc fixes

  core/lib:
   - new typeof_member() macro including some users, by Alexey Dobriyan

   - make BIT() and GENMASK() available in asm, by Masahiro Yamada

   - changed LIST_POISON2 on x86_64 to 0xdead000000000122 for better
     code generation, by Alexey Dobriyan

   - rbtree code size optimizations, by Michel Lespinasse

   - convert struct pid count to refcount_t, by Joel Fernandes

  get_maintainer.pl:
   - add --no-moderated switch to skip moderated ML's, by Joe Perches

  misc:
   - ptrace PTRACE_GET_SYSCALL_INFO interface

   - coda updates

   - gdb scripts, various"

[ Using merge message suggestion from Vlastimil Babka, with some editing - Linus ]

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (100 commits)
  fs/select.c: use struct_size() in kmalloc()
  mm: add account_locked_vm utility function
  arm64: mm: implement pte_devmap support
  mm: introduce ARCH_HAS_PTE_DEVMAP
  mm: clean up is_device_*_page() definitions
  mm/mmap: move common defines to mman-common.h
  mm: move MAP_SYNC to asm-generic/mman-common.h
  device-dax: "Hotremove" persistent memory that is used like normal RAM
  mm/hotplug: make remove_memory() interface usable
  device-dax: fix memory and resource leak if hotplug fails
  include/linux/lz4.h: fix spelling and copy-paste errors in documentation
  ipc/mqueue.c: only perform resource calculation if user valid
  include/asm-generic/bug.h: fix "cut here" for WARN_ON for __WARN_TAINT architectures
  scripts/gdb: add helpers to find and list devices
  scripts/gdb: add lx-genpd-summary command
  drivers/pps/pps.c: clear offset flags in PPS_SETPARAMS ioctl
  kernel/pid.c: convert struct pid count to refcount_t
  drivers/rapidio/devices/rio_mport_cdev.c: NUL terminate some strings
  select: shift restore_saved_sigmask_unless() into poll_select_copy_remaining()
  select: change do_poll() to return -ERESTARTNOHAND rather than -EINTR
  ...

1 files changed, 133 insertions, 0 deletions

diff --git a/tools/testing/selftests/proc/setns-sysvipc.c b/tools/testing/selftests/proc/setns-sysvipc.c
new file mode 100644
index 000000000000..903890c5e587
--- /dev/null
+++ b/tools/testing/selftests/proc/setns-sysvipc.c
@@ -0,0 +1,133 @@
+/*
+ * Copyright © 2019 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+/*
+ * Test that setns(CLONE_NEWIPC) points to new /proc/sysvipc content even
+ * if old one is in dcache.
+ */
+#undef NDEBUG
+#include <assert.h>
+#include <errno.h>
+#include <stdio.h>
+#include <sched.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/ipc.h>
+#include <sys/shm.h>
+
+static pid_t pid = -1;
+
+static void f(void)
+{
+        if (pid > 0) {
+                kill(pid, SIGTERM);
+        }
+}
+
+int main(void)
+{
+        int fd[2];
+        char _ = 0;
+        int nsfd;
+
+        atexit(f);
+
+        /* Check for priviledges and syscall availability straight away. */
+        if (unshare(CLONE_NEWIPC) == -1) {
+                if (errno == ENOSYS || errno == EPERM) {
+                        return 4;
+                }
+                return 1;
+        }
+        /* Distinguisher between two otherwise empty IPC namespaces. */
+        if (shmget(IPC_PRIVATE, 1, IPC_CREAT) == -1) {
+                return 1;
+        }
+
+        if (pipe(fd) == -1) {
+                return 1;
+        }
+
+        pid = fork();
+        if (pid == -1) {
+                return 1;
+        }
+
+        if (pid == 0) {
+                if (unshare(CLONE_NEWIPC) == -1) {
+                        return 1;
+                }
+
+                if (write(fd[1], &_, 1) != 1) {
+                        return 1;
+                }
+
+                pause();
+
+                return 0;
+        }
+
+        if (read(fd[0], &_, 1) != 1) {
+                return 1;
+        }
+
+        {
+                char buf[64];
+                snprintf(buf, sizeof(buf), "/proc/%u/ns/ipc", pid);
+                nsfd = open(buf, O_RDONLY);
+                if (nsfd == -1) {
+                        return 1;
+                }
+        }
+
+        /* Reliably pin dentry into dcache. */
+        (void)open("/proc/sysvipc/shm", O_RDONLY);
+
+        if (setns(nsfd, CLONE_NEWIPC) == -1) {
+                return 1;
+        }
+
+        kill(pid, SIGTERM);
+        pid = 0;
+
+        {
+                char buf[4096];
+                ssize_t rv;
+                int fd;
+
+                fd = open("/proc/sysvipc/shm", O_RDONLY);
+                if (fd == -1) {
+                        return 1;
+                }
+
+#define S32 "       key      shmid perms       size  cpid  lpid nattch   uid   gid  cuid  cgid      atime      dtime      ctime        rss       swap\n"
+#define S64 "       key      shmid perms                  size  cpid  lpid nattch   uid   gid  cuid  cgid      atime      dtime      ctime                   rss                  swap\n"
+                rv = read(fd, buf, sizeof(buf));
+                if (rv == strlen(S32)) {
+                        assert(memcmp(buf, S32, strlen(S32)) == 0);
+                } else if (rv == strlen(S64)) {
+                        assert(memcmp(buf, S64, strlen(S64)) == 0);
+                } else {
+                        assert(0);
+                }
+        }
+
+        return 0;
+}