1. 27 4月, 2017 5 次提交
  2. 13 4月, 2017 1 次提交
  3. 07 4月, 2017 2 次提交
  4. 24 3月, 2017 1 次提交
  5. 20 3月, 2017 2 次提交
    • K
      x86/arch_prctl: Add ARCH_[GET|SET]_CPUID · e9ea1e7f
      Kyle Huey 提交于
      Intel supports faulting on the CPUID instruction beginning with Ivy Bridge.
      When enabled, the processor will fault on attempts to execute the CPUID
      instruction with CPL>0. Exposing this feature to userspace will allow a
      ptracer to trap and emulate the CPUID instruction.
      
      When supported, this feature is controlled by toggling bit 0 of
      MSR_MISC_FEATURES_ENABLES. It is documented in detail in Section 2.3.2 of
      https://bugzilla.kernel.org/attachment.cgi?id=243991
      
      Implement a new pair of arch_prctls, available on both x86-32 and x86-64.
      
      ARCH_GET_CPUID: Returns the current CPUID state, either 0 if CPUID faulting
          is enabled (and thus the CPUID instruction is not available) or 1 if
          CPUID faulting is not enabled.
      
      ARCH_SET_CPUID: Set the CPUID state to the second argument. If
          cpuid_enabled is 0 CPUID faulting will be activated, otherwise it will
          be deactivated. Returns ENODEV if CPUID faulting is not supported on
          this system.
      
      The state of the CPUID faulting flag is propagated across forks, but reset
      upon exec.
      Signed-off-by: NKyle Huey <khuey@kylehuey.com>
      Cc: Grzegorz Andrejczuk <grzegorz.andrejczuk@intel.com>
      Cc: kvm@vger.kernel.org
      Cc: Radim Krčmář <rkrcmar@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: linux-kselftest@vger.kernel.org
      Cc: Nadav Amit <nadav.amit@gmail.com>
      Cc: Robert O'Callahan <robert@ocallahan.org>
      Cc: Richard Weinberger <richard@nod.at>
      Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Len Brown <len.brown@intel.com>
      Cc: Shuah Khan <shuah@kernel.org>
      Cc: user-mode-linux-devel@lists.sourceforge.net
      Cc: Jeff Dike <jdike@addtoit.com>
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      Cc: user-mode-linux-user@lists.sourceforge.net
      Cc: David Matlack <dmatlack@google.com>
      Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
      Cc: Dmitry Safonov <dsafonov@virtuozzo.com>
      Cc: linux-fsdevel@vger.kernel.org
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Link: http://lkml.kernel.org/r/20170320081628.18952-9-khuey@kylehuey.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      e9ea1e7f
    • K
      x86/syscalls/32: Wire up arch_prctl on x86-32 · 79170fda
      Kyle Huey 提交于
      Hook up arch_prctl to call do_arch_prctl() on x86-32, and in 32 bit compat
      mode on x86-64. This allows to have arch_prctls that are not specific to 64
      bits.
      
      On UML, simply stub out this syscall.
      Signed-off-by: NKyle Huey <khuey@kylehuey.com>
      Cc: Grzegorz Andrejczuk <grzegorz.andrejczuk@intel.com>
      Cc: kvm@vger.kernel.org
      Cc: Radim Krčmář <rkrcmar@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: linux-kselftest@vger.kernel.org
      Cc: Nadav Amit <nadav.amit@gmail.com>
      Cc: Robert O'Callahan <robert@ocallahan.org>
      Cc: Richard Weinberger <richard@nod.at>
      Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Len Brown <len.brown@intel.com>
      Cc: Shuah Khan <shuah@kernel.org>
      Cc: user-mode-linux-devel@lists.sourceforge.net
      Cc: Jeff Dike <jdike@addtoit.com>
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      Cc: user-mode-linux-user@lists.sourceforge.net
      Cc: David Matlack <dmatlack@google.com>
      Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
      Cc: Dmitry Safonov <dsafonov@virtuozzo.com>
      Cc: linux-fsdevel@vger.kernel.org
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Link: http://lkml.kernel.org/r/20170320081628.18952-7-khuey@kylehuey.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      79170fda
  6. 17 3月, 2017 2 次提交
  7. 14 3月, 2017 1 次提交
  8. 13 3月, 2017 1 次提交
    • D
      bpf: improve read-only handling · 65869a47
      Daniel Borkmann 提交于
      Improve bpf_{prog,jit_binary}_{un,}lock_ro() by throwing a
      one-time warning in case of an error when the image couldn't
      be set read-only, and also mark struct bpf_prog as locked when
      bpf_prog_lock_ro() was called.
      
      Reason for the latter is that bpf_prog_unlock_ro() is called from
      various places including error paths, and we shouldn't mess with
      page attributes when really not needed.
      
      For bpf_jit_binary_unlock_ro() this is not needed as jited flag
      implicitly indicates this, thus for archs with ARCH_HAS_SET_MEMORY
      we're guaranteed to have a previously locked image. Overall, this
      should also help us to identify any further potential issues with
      set_memory_*() helpers.
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      65869a47
  9. 11 3月, 2017 3 次提交
  10. 10 3月, 2017 9 次提交
    • D
      net: Work around lockdep limitation in sockets that use sockets · cdfbabfb
      David Howells 提交于
      Lockdep issues a circular dependency warning when AFS issues an operation
      through AF_RXRPC from a context in which the VFS/VM holds the mmap_sem.
      
      The theory lockdep comes up with is as follows:
      
       (1) If the pagefault handler decides it needs to read pages from AFS, it
           calls AFS with mmap_sem held and AFS begins an AF_RXRPC call, but
           creating a call requires the socket lock:
      
      	mmap_sem must be taken before sk_lock-AF_RXRPC
      
       (2) afs_open_socket() opens an AF_RXRPC socket and binds it.  rxrpc_bind()
           binds the underlying UDP socket whilst holding its socket lock.
           inet_bind() takes its own socket lock:
      
      	sk_lock-AF_RXRPC must be taken before sk_lock-AF_INET
      
       (3) Reading from a TCP socket into a userspace buffer might cause a fault
           and thus cause the kernel to take the mmap_sem, but the TCP socket is
           locked whilst doing this:
      
      	sk_lock-AF_INET must be taken before mmap_sem
      
      However, lockdep's theory is wrong in this instance because it deals only
      with lock classes and not individual locks.  The AF_INET lock in (2) isn't
      really equivalent to the AF_INET lock in (3) as the former deals with a
      socket entirely internal to the kernel that never sees userspace.  This is
      a limitation in the design of lockdep.
      
      Fix the general case by:
      
       (1) Double up all the locking keys used in sockets so that one set are
           used if the socket is created by userspace and the other set is used
           if the socket is created by the kernel.
      
       (2) Store the kern parameter passed to sk_alloc() in a variable in the
           sock struct (sk_kern_sock).  This informs sock_lock_init(),
           sock_init_data() and sk_clone_lock() as to the lock keys to be used.
      
           Note that the child created by sk_clone_lock() inherits the parent's
           kern setting.
      
       (3) Add a 'kern' parameter to ->accept() that is analogous to the one
           passed in to ->create() that distinguishes whether kernel_accept() or
           sys_accept4() was the caller and can be passed to sk_alloc().
      
           Note that a lot of accept functions merely dequeue an already
           allocated socket.  I haven't touched these as the new socket already
           exists before we get the parameter.
      
           Note also that there are a couple of places where I've made the accepted
           socket unconditionally kernel-based:
      
      	irda_accept()
      	rds_rcp_accept_one()
      	tcp_accept_from_sock()
      
           because they follow a sock_create_kern() and accept off of that.
      
      Whilst creating this, I noticed that lustre and ocfs don't create sockets
      through sock_create_kern() and thus they aren't marked as for-kernel,
      though they appear to be internal.  I wonder if these should do that so
      that they use the new set of lock keys.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      cdfbabfb
    • A
      userfaultfd: non-cooperative: userfaultfd_remove revalidate vma in MADV_DONTNEED · 70ccb92f
      Andrea Arcangeli 提交于
      userfaultfd_remove() has to be execute before zapping the pagetables or
      UFFDIO_COPY could keep filling pages after zap_page_range returned,
      which would result in non zero data after a MADV_DONTNEED.
      
      However userfaultfd_remove() may have to release the mmap_sem.  This was
      handled correctly in MADV_REMOVE, but MADV_DONTNEED accessed a
      potentially stale vma (the very vma passed to zap_page_range(vma, ...)).
      
      The fix consists in revalidating the vma in case userfaultfd_remove()
      had to release the mmap_sem.
      
      This also optimizes away an unnecessary down_read/up_read in the
      MADV_REMOVE case if UFFD_EVENT_FORK had to be delivered.
      
      It all remains zero runtime cost in case CONFIG_USERFAULTFD=n as
      userfaultfd_remove() will be defined as "true" at build time.
      
      Link: http://lkml.kernel.org/r/20170302173738.18994-3-aarcange@redhat.comSigned-off-by: NAndrea Arcangeli <aarcange@redhat.com>
      Acked-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
      Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
      Cc: Mike Kravetz <mike.kravetz@oracle.com>
      Cc: Pavel Emelyanov <xemul@parallels.com>
      Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      70ccb92f
    • Y
      mm/vmstats: add thp_split_pud event for clarity · ce9311cf
      Yisheng Xie 提交于
      We added support for PUD-sized transparent hugepages, however we count
      the event "thp split pud" into thp_split_pmd event.
      
      To separate the event count of thp split pud from pmd, add a new event
      named thp_split_pud.
      
      Link: http://lkml.kernel.org/r/1488282380-5076-1-git-send-email-xieyisheng1@huawei.comSigned-off-by: NYisheng Xie <xieyisheng1@huawei.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Sebastian Siewior <bigeasy@linutronix.de>
      Cc: Hugh Dickins <hughd@google.com>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
      Cc: Mel Gorman <mgorman@techsingularity.net>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Ebru Akagunduz <ebru.akagunduz@gmail.com>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Hanjun Guo <guohanjun@huawei.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      ce9311cf
    • A
      include/linux/fs.h: fix unsigned enum warning with gcc-4.2 · cbfd0c10
      Arnd Bergmann 提交于
      With arm-linux-gcc-4.2, almost every file we build in the kernel ends up
      with this warning:
      
        include/linux/fs.h:2648: warning: comparison of unsigned expression < 0 is always false
      
      Later versions don't have this problem, but it's easy enough to work
      around.
      
      Link: http://lkml.kernel.org/r/20161216105634.235457-12-arnd@arndb.deSigned-off-by: NArnd Bergmann <arnd@arndb.de>
      Cc: Russell King <rmk+kernel@armlinux.org.uk>
      Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      cbfd0c10
    • A
      userfaultfd: non-cooperative: rollback userfaultfd_exit · dd0db88d
      Andrea Arcangeli 提交于
      Patch series "userfaultfd non-cooperative further update for 4.11 merge
      window".
      
      Unfortunately I noticed one relevant bug in userfaultfd_exit while doing
      more testing.  I've been doing testing before and this was also tested
      by kbuild bot and exercised by the selftest, but this bug never
      reproduced before.
      
      I dropped userfaultfd_exit as result.  I dropped it because of
      implementation difficulty in receiving signals in __mmput and because I
      think -ENOSPC as result from the background UFFDIO_COPY should be enough
      already.
      
      Before I decided to remove userfaultfd_exit, I noticed userfaultfd_exit
      wasn't exercised by the selftest and when I tried to exercise it, after
      moving it to a more correct place in __mmput where it would make more
      sense and where the vma list is stable, it resulted in the
      event_wait_completion in D state.  So then I added the second patch to
      be sure even if we call userfaultfd_event_wait_completion too late
      during task exit(), we won't risk to generate tasks in D state.  The
      same check exists in handle_userfault() for the same reason, except it
      makes a difference there, while here is just a robustness check and it's
      run under WARN_ON_ONCE.
      
      While looking at the userfaultfd_event_wait_completion() function I
      looked back at its callers too while at it and I think it's not ok to
      stop executing dup_fctx on the fcs list because we relay on
      userfaultfd_event_wait_completion to execute
      userfaultfd_ctx_put(fctx->orig) which is paired against
      userfaultfd_ctx_get(fctx->orig) in dup_userfault just before
      list_add(fcs).  This change only takes care of fctx->orig but this area
      also needs further review looking for similar problems in fctx->new.
      
      The only patch that is urgent is the first because it's an use after
      free during a SMP race condition that affects all processes if
      CONFIG_USERFAULTFD=y.  Very hard to reproduce though and probably
      impossible without SLUB poisoning enabled.
      
      This patch (of 3):
      
      I once reproduced this oops with the userfaultfd selftest, it's not
      easily reproducible and it requires SLUB poisoning to reproduce.
      
          general protection fault: 0000 [#1] SMP
          Modules linked in:
          CPU: 2 PID: 18421 Comm: userfaultfd Tainted: G               ------------ T 3.10.0+ #15
          Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.1-0-g8891697-prebuilt.qemu-project.org 04/01/2014
          task: ffff8801f83b9440 ti: ffff8801f833c000 task.ti: ffff8801f833c000
          RIP: 0010:[<ffffffff81451299>]  [<ffffffff81451299>] userfaultfd_exit+0x29/0xa0
          RSP: 0018:ffff8801f833fe80  EFLAGS: 00010202
          RAX: ffff8801f833ffd8 RBX: 6b6b6b6b6b6b6b6b RCX: ffff8801f83b9440
          RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8800baf18600
          RBP: ffff8801f833fee8 R08: 0000000000000000 R09: 0000000000000001
          R10: 0000000000000000 R11: ffffffff8127ceb3 R12: 0000000000000000
          R13: ffff8800baf186b0 R14: ffff8801f83b99f8 R15: 00007faed746c700
          FS:  0000000000000000(0000) GS:ffff88023fc80000(0000) knlGS:0000000000000000
          CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
          CR2: 00007faf0966f028 CR3: 0000000001bc6000 CR4: 00000000000006e0
          DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
          DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
          Call Trace:
            do_exit+0x297/0xd10
            SyS_exit+0x17/0x20
            tracesys+0xdd/0xe2
          Code: 00 00 66 66 66 66 90 55 48 89 e5 41 54 53 48 83 ec 58 48 8b 1f 48 85 db 75 11 eb 73 66 0f 1f 44 00 00 48 8b 5b 10 48 85 db 74 64 <4c> 8b a3 b8 00 00 00 4d 85 e4 74 eb 41 f6 84 24 2c 01 00 00 80
          RIP  [<ffffffff81451299>] userfaultfd_exit+0x29/0xa0
           RSP <ffff8801f833fe80>
          ---[ end trace 9fecd6dcb442846a ]---
      
      In the debugger I located the "mm" pointer in the stack and walking
      mm->mmap->vm_next through the end shows the vma->vm_next list is fully
      consistent and it is null terminated list as expected.  So this has to
      be an SMP race condition where userfaultfd_exit was running while the
      vma list was being modified by another CPU.
      
      When userfaultfd_exit() run one of the ->vm_next pointers pointed to
      SLAB_POISON (RBX is the vma pointer and is 0x6b6b..).
      
      The reason is that it's not running in __mmput but while there are still
      other threads running and it's not holding the mmap_sem (it can't as it
      has to wait the even to be received by the manager).  So this is an use
      after free that was happening for all processes.
      
      One more implementation problem aside from the race condition:
      userfaultfd_exit has really to check a flag in mm->flags before walking
      the vma or it's going to slowdown the exit() path for regular tasks.
      
      One more implementation problem: at that point signals can't be
      delivered so it would also create a task in D state if the manager
      doesn't read the event.
      
      The major design issue: it overall looks superfluous as the manager can
      check for -ENOSPC in the background transfer:
      
      	if (mmget_not_zero(ctx->mm)) {
      [..]
      	} else {
      		return -ENOSPC;
      	}
      
      It's safer to roll it back and re-introduce it later if at all.
      
      [rppt@linux.vnet.ibm.com: documentation fixup after removal of UFFD_EVENT_EXIT]
        Link: http://lkml.kernel.org/r/1488345437-4364-1-git-send-email-rppt@linux.vnet.ibm.com
      Link: http://lkml.kernel.org/r/20170224181957.19736-2-aarcange@redhat.comSigned-off-by: NAndrea Arcangeli <aarcange@redhat.com>
      Signed-off-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
      Acked-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
      Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
      Cc: Mike Kravetz <mike.kravetz@oracle.com>
      Cc: Pavel Emelyanov <xemul@parallels.com>
      Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      dd0db88d
    • M
      scripts/spelling.txt: add "disble(d)" pattern and fix typo instances · 8a1115ff
      Masahiro Yamada 提交于
      Fix typos and add the following to the scripts/spelling.txt:
      
        disble||disable
        disbled||disabled
      
      I kept the TSL2563_INT_DISBLED in /drivers/iio/light/tsl2563.c
      untouched.  The macro is not referenced at all, but this commit is
      touching only comment blocks just in case.
      
      Link: http://lkml.kernel.org/r/1481573103-11329-20-git-send-email-yamada.masahiro@socionext.comSigned-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      8a1115ff
    • A
      bpf: convert htab map to hlist_nulls · 4fe84359
      Alexei Starovoitov 提交于
      when all map elements are pre-allocated one cpu can delete and reuse htab_elem
      while another cpu is still walking the hlist. In such case the lookup may
      miss the element. Convert hlist to hlist_nulls to avoid such scenario.
      When bucket lock is taken there is no need to take such precautions,
      so only convert map_lookup and map_get_next to nulls.
      The race window is extremely small and only reproducible with explicit
      udelay() inside lookup_nulls_elem_raw()
      
      Similar to hlist add hlist_nulls_for_each_entry_safe() and
      hlist_nulls_entry_safe() helpers.
      
      Fixes: 6c905981 ("bpf: pre-allocate hash map elements")
      Reported-by: NJonathan Perry <jonperry@fb.com>
      Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
      Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      4fe84359
    • K
      mm: convert generic code to 5-level paging · c2febafc
      Kirill A. Shutemov 提交于
      Convert all non-architecture-specific code to 5-level paging.
      
      It's mostly mechanical adding handling one more page table level in
      places where we deal with pud_t.
      Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Acked-by: NMichal Hocko <mhocko@suse.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c2febafc
    • K
      asm-generic: introduce 5level-fixup.h · 505a60e2
      Kirill A. Shutemov 提交于
      We are going to switch core MM to 5-level paging abstraction.
      
      This is preparation step which adds <asm-generic/5level-fixup.h>
      As with 4level-fixup.h, the new header allows quickly make all
      architectures compatible with 5-level paging in core MM.
      
      In long run we would like to switch architectures to properly folded p4d
      level by using <asm-generic/pgtable-nop4d.h>, but it requires more
      changes to arch-specific code.
      Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Acked-by: NMichal Hocko <mhocko@suse.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      505a60e2
  11. 09 3月, 2017 2 次提交
    • L
      sched/headers: fix up header file dependency on <linux/sched/signal.h> · bd0f9b35
      Linus Torvalds 提交于
      The scheduler header file split and cleanups ended up exposing a few
      nasty header file dependencies, and in particular it showed how we in
      <linux/wait.h> ended up depending on "signal_pending()", which now comes
      from <linux/sched/signal.h>.
      
      That's a very subtle and annoying dependency, which already caused a
      semantic merge conflict (see commit e58bc927 "Pull overlayfs updates
      from Miklos Szeredi", which added that fixup in the merge commit).
      
      It turns out that we can avoid this dependency _and_ improve code
      generation by moving the guts of the fairly nasty helper #define
      __wait_event_interruptible_locked() to out-of-line code.  The code that
      includes the signal_pending() check is all in the slow-path where we
      actually go to sleep waiting for the event anyway, so using a helper
      function is the right thing to do.
      
      Using a helper function is also what we already did for the non-locked
      versions, see the "__wait_event*()" macros and the "prepare_to_wait*()"
      set of helper functions.
      
      We might want to try to unify all these macro games, we have a _lot_ of
      subtly different wait-event loops.  But this is the minimal patch to fix
      the annoying header dependency.
      Acked-by: NIngo Molnar <mingo@kernel.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      bd0f9b35
    • J
      Revert "scsi, block: fix duplicate bdi name registration crashes" · c01228db
      Jan Kara 提交于
      This reverts commit 0dba1314. It causes
      leaking of device numbers for SCSI when SCSI registers multiple gendisks
      for one request_queue in succession. It can be easily reproduced using
      Omar's script [1] on kernel with CONFIG_DEBUG_TEST_DRIVER_REMOVE.
      Furthermore the protection provided by this commit is not needed anymore
      as the problem it was fixing got also fixed by commit 165a5e22
      "block: Move bdi_unregister() to del_gendisk()".
      
      [1]: http://marc.info/?l=linux-block&m=148554717109098&w=2Signed-off-by: NJan Kara <jack@suse.cz>
      Acked-by: NDan Williams <dan.j.williams@intel.com>
      Tested-by: NOmar Sandoval <osandov@fb.com>
      Signed-off-by: NJens Axboe <axboe@fb.com>
      c01228db
  12. 08 3月, 2017 1 次提交
    • E
      dccp: fix use-after-free in dccp_feat_activate_values · 62f8f4d9
      Eric Dumazet 提交于
      Dmitry reported crashes in DCCP stack [1]
      
      Problem here is that when I got rid of listener spinlock, I missed the
      fact that DCCP stores a complex state in struct dccp_request_sock,
      while TCP does not.
      
      Since multiple cpus could access it at the same time, we need to add
      protection.
      
      [1]
      BUG: KASAN: use-after-free in dccp_feat_activate_values+0x967/0xab0
      net/dccp/feat.c:1541 at addr ffff88003713be68
      Read of size 8 by task syz-executor2/8457
      CPU: 2 PID: 8457 Comm: syz-executor2 Not tainted 4.10.0-rc7+ #127
      Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
      Call Trace:
       <IRQ>
       __dump_stack lib/dump_stack.c:15 [inline]
       dump_stack+0x292/0x398 lib/dump_stack.c:51
       kasan_object_err+0x1c/0x70 mm/kasan/report.c:162
       print_address_description mm/kasan/report.c:200 [inline]
       kasan_report_error mm/kasan/report.c:289 [inline]
       kasan_report.part.1+0x20e/0x4e0 mm/kasan/report.c:311
       kasan_report mm/kasan/report.c:332 [inline]
       __asan_report_load8_noabort+0x29/0x30 mm/kasan/report.c:332
       dccp_feat_activate_values+0x967/0xab0 net/dccp/feat.c:1541
       dccp_create_openreq_child+0x464/0x610 net/dccp/minisocks.c:121
       dccp_v6_request_recv_sock+0x1f6/0x1960 net/dccp/ipv6.c:457
       dccp_check_req+0x335/0x5a0 net/dccp/minisocks.c:186
       dccp_v6_rcv+0x69e/0x1d00 net/dccp/ipv6.c:711
       ip6_input_finish+0x46d/0x17a0 net/ipv6/ip6_input.c:279
       NF_HOOK include/linux/netfilter.h:257 [inline]
       ip6_input+0xdb/0x590 net/ipv6/ip6_input.c:322
       dst_input include/net/dst.h:507 [inline]
       ip6_rcv_finish+0x289/0x890 net/ipv6/ip6_input.c:69
       NF_HOOK include/linux/netfilter.h:257 [inline]
       ipv6_rcv+0x12ec/0x23d0 net/ipv6/ip6_input.c:203
       __netif_receive_skb_core+0x1ae5/0x3400 net/core/dev.c:4190
       __netif_receive_skb+0x2a/0x170 net/core/dev.c:4228
       process_backlog+0xe5/0x6c0 net/core/dev.c:4839
       napi_poll net/core/dev.c:5202 [inline]
       net_rx_action+0xe70/0x1900 net/core/dev.c:5267
       __do_softirq+0x2fb/0xb7d kernel/softirq.c:284
       do_softirq_own_stack+0x1c/0x30 arch/x86/entry/entry_64.S:902
       </IRQ>
       do_softirq.part.17+0x1e8/0x230 kernel/softirq.c:328
       do_softirq kernel/softirq.c:176 [inline]
       __local_bh_enable_ip+0x1f2/0x200 kernel/softirq.c:181
       local_bh_enable include/linux/bottom_half.h:31 [inline]
       rcu_read_unlock_bh include/linux/rcupdate.h:971 [inline]
       ip6_finish_output2+0xbb0/0x23d0 net/ipv6/ip6_output.c:123
       ip6_finish_output+0x302/0x960 net/ipv6/ip6_output.c:148
       NF_HOOK_COND include/linux/netfilter.h:246 [inline]
       ip6_output+0x1cb/0x8d0 net/ipv6/ip6_output.c:162
       ip6_xmit+0xcdf/0x20d0 include/net/dst.h:501
       inet6_csk_xmit+0x320/0x5f0 net/ipv6/inet6_connection_sock.c:179
       dccp_transmit_skb+0xb09/0x1120 net/dccp/output.c:141
       dccp_xmit_packet+0x215/0x760 net/dccp/output.c:280
       dccp_write_xmit+0x168/0x1d0 net/dccp/output.c:362
       dccp_sendmsg+0x79c/0xb10 net/dccp/proto.c:796
       inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:744
       sock_sendmsg_nosec net/socket.c:635 [inline]
       sock_sendmsg+0xca/0x110 net/socket.c:645
       SYSC_sendto+0x660/0x810 net/socket.c:1687
       SyS_sendto+0x40/0x50 net/socket.c:1655
       entry_SYSCALL_64_fastpath+0x1f/0xc2
      RIP: 0033:0x4458b9
      RSP: 002b:00007f8ceb77bb58 EFLAGS: 00000282 ORIG_RAX: 000000000000002c
      RAX: ffffffffffffffda RBX: 0000000000000017 RCX: 00000000004458b9
      RDX: 0000000000000023 RSI: 0000000020e60000 RDI: 0000000000000017
      RBP: 00000000006e1b90 R08: 00000000200f9fe1 R09: 0000000000000020
      R10: 0000000000008010 R11: 0000000000000282 R12: 00000000007080a8
      R13: 0000000000000000 R14: 00007f8ceb77c9c0 R15: 00007f8ceb77c700
      Object at ffff88003713be50, in cache kmalloc-64 size: 64
      Allocated:
      PID = 8446
       save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57
       save_stack+0x43/0xd0 mm/kasan/kasan.c:502
       set_track mm/kasan/kasan.c:514 [inline]
       kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:605
       kmem_cache_alloc_trace+0x82/0x270 mm/slub.c:2738
       kmalloc include/linux/slab.h:490 [inline]
       dccp_feat_entry_new+0x214/0x410 net/dccp/feat.c:467
       dccp_feat_push_change+0x38/0x220 net/dccp/feat.c:487
       __feat_register_sp+0x223/0x2f0 net/dccp/feat.c:741
       dccp_feat_propagate_ccid+0x22b/0x2b0 net/dccp/feat.c:949
       dccp_feat_server_ccid_dependencies+0x1b3/0x250 net/dccp/feat.c:1012
       dccp_make_response+0x1f1/0xc90 net/dccp/output.c:423
       dccp_v6_send_response+0x4ec/0xc20 net/dccp/ipv6.c:217
       dccp_v6_conn_request+0xaba/0x11b0 net/dccp/ipv6.c:377
       dccp_rcv_state_process+0x51e/0x1650 net/dccp/input.c:606
       dccp_v6_do_rcv+0x213/0x350 net/dccp/ipv6.c:632
       sk_backlog_rcv include/net/sock.h:893 [inline]
       __sk_receive_skb+0x36f/0xcc0 net/core/sock.c:479
       dccp_v6_rcv+0xba5/0x1d00 net/dccp/ipv6.c:742
       ip6_input_finish+0x46d/0x17a0 net/ipv6/ip6_input.c:279
       NF_HOOK include/linux/netfilter.h:257 [inline]
       ip6_input+0xdb/0x590 net/ipv6/ip6_input.c:322
       dst_input include/net/dst.h:507 [inline]
       ip6_rcv_finish+0x289/0x890 net/ipv6/ip6_input.c:69
       NF_HOOK include/linux/netfilter.h:257 [inline]
       ipv6_rcv+0x12ec/0x23d0 net/ipv6/ip6_input.c:203
       __netif_receive_skb_core+0x1ae5/0x3400 net/core/dev.c:4190
       __netif_receive_skb+0x2a/0x170 net/core/dev.c:4228
       process_backlog+0xe5/0x6c0 net/core/dev.c:4839
       napi_poll net/core/dev.c:5202 [inline]
       net_rx_action+0xe70/0x1900 net/core/dev.c:5267
       __do_softirq+0x2fb/0xb7d kernel/softirq.c:284
      Freed:
      PID = 15
       save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57
       save_stack+0x43/0xd0 mm/kasan/kasan.c:502
       set_track mm/kasan/kasan.c:514 [inline]
       kasan_slab_free+0x73/0xc0 mm/kasan/kasan.c:578
       slab_free_hook mm/slub.c:1355 [inline]
       slab_free_freelist_hook mm/slub.c:1377 [inline]
       slab_free mm/slub.c:2954 [inline]
       kfree+0xe8/0x2b0 mm/slub.c:3874
       dccp_feat_entry_destructor.part.4+0x48/0x60 net/dccp/feat.c:418
       dccp_feat_entry_destructor net/dccp/feat.c:416 [inline]
       dccp_feat_list_pop net/dccp/feat.c:541 [inline]
       dccp_feat_activate_values+0x57f/0xab0 net/dccp/feat.c:1543
       dccp_create_openreq_child+0x464/0x610 net/dccp/minisocks.c:121
       dccp_v6_request_recv_sock+0x1f6/0x1960 net/dccp/ipv6.c:457
       dccp_check_req+0x335/0x5a0 net/dccp/minisocks.c:186
       dccp_v6_rcv+0x69e/0x1d00 net/dccp/ipv6.c:711
       ip6_input_finish+0x46d/0x17a0 net/ipv6/ip6_input.c:279
       NF_HOOK include/linux/netfilter.h:257 [inline]
       ip6_input+0xdb/0x590 net/ipv6/ip6_input.c:322
       dst_input include/net/dst.h:507 [inline]
       ip6_rcv_finish+0x289/0x890 net/ipv6/ip6_input.c:69
       NF_HOOK include/linux/netfilter.h:257 [inline]
       ipv6_rcv+0x12ec/0x23d0 net/ipv6/ip6_input.c:203
       __netif_receive_skb_core+0x1ae5/0x3400 net/core/dev.c:4190
       __netif_receive_skb+0x2a/0x170 net/core/dev.c:4228
       process_backlog+0xe5/0x6c0 net/core/dev.c:4839
       napi_poll net/core/dev.c:5202 [inline]
       net_rx_action+0xe70/0x1900 net/core/dev.c:5267
       __do_softirq+0x2fb/0xb7d kernel/softirq.c:284
      Memory state around the buggy address:
       ffff88003713bd00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
       ffff88003713bd80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
      >ffff88003713be00: fc fc fc fc fc fc fc fc fc fc fb fb fb fb fb fb
                                                                ^
      
      Fixes: 079096f1 ("tcp/dccp: install syn_recv requests into ehash table")
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Reported-by: NDmitry Vyukov <dvyukov@google.com>
      Tested-by: NDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      62f8f4d9
  13. 07 3月, 2017 2 次提交
  14. 06 3月, 2017 3 次提交
  15. 03 3月, 2017 5 次提交
    • S
      jump_label: Add comment about initialization order for anonymous unions · b17ef2ed
      Steven Rostedt (VMware) 提交于
      Commit 3821fd35 ("jump_label: Reduce the size of struct static_key")
      broke old compilers that could not handle static initialization of anonymous
      unions. Boris fixed it with a patch that added brackets around the static
      initializer. But this creates a dependency between those initializers and
      the structure's order of its fields. Document this dependency in case new
      fields are added to struct static_key in the future.
      Noted-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
      Suggested-by: NChris Mason <clm@fb.com>
      Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
      b17ef2ed
    • B
      jump_label: Fix anonymous union initialization · cd8d860d
      Boris Ostrovsky 提交于
      Pre-4.6 gcc do not allow direct static initialization of members of
      anonymous structs/unions. After commit 3821fd35 ("jump_label:
      Reduce the size of struct static_key") STATIC_KEY_INIT_{TRUE|FALSE}
      definitions cannot be compiled with those older compilers.
      
      Placing initializers inside curved brackets works around this problem.
      
      Link: http://lkml.kernel.org/r/1488299542-30765-1-git-send-email-boris.ostrovsky@oracle.com
      
      Fixes: 3821fd35 ("jump_label: Reduce the size of struct static_key")
      Reviewed-by: NJason Baron <jbaron@akamai.com>
      Compiled-by: NChris Mason <clm@fb.com>
      Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
      Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>
      cd8d860d
    • D
      statx: Add a system call to make enhanced file info available · a528d35e
      David Howells 提交于
      Add a system call to make extended file information available, including
      file creation and some attribute flags where available through the
      underlying filesystem.
      
      The getattr inode operation is altered to take two additional arguments: a
      u32 request_mask and an unsigned int flags that indicate the
      synchronisation mode.  This change is propagated to the vfs_getattr*()
      function.
      
      Functions like vfs_stat() are now inline wrappers around new functions
      vfs_statx() and vfs_statx_fd() to reduce stack usage.
      
      ========
      OVERVIEW
      ========
      
      The idea was initially proposed as a set of xattrs that could be retrieved
      with getxattr(), but the general preference proved to be for a new syscall
      with an extended stat structure.
      
      A number of requests were gathered for features to be included.  The
      following have been included:
      
       (1) Make the fields a consistent size on all arches and make them large.
      
       (2) Spare space, request flags and information flags are provided for
           future expansion.
      
       (3) Better support for the y2038 problem [Arnd Bergmann] (tv_sec is an
           __s64).
      
       (4) Creation time: The SMB protocol carries the creation time, which could
           be exported by Samba, which will in turn help CIFS make use of
           FS-Cache as that can be used for coherency data (stx_btime).
      
           This is also specified in NFSv4 as a recommended attribute and could
           be exported by NFSD [Steve French].
      
       (5) Lightweight stat: Ask for just those details of interest, and allow a
           netfs (such as NFS) to approximate anything not of interest, possibly
           without going to the server [Trond Myklebust, Ulrich Drepper, Andreas
           Dilger] (AT_STATX_DONT_SYNC).
      
       (6) Heavyweight stat: Force a netfs to go to the server, even if it thinks
           its cached attributes are up to date [Trond Myklebust]
           (AT_STATX_FORCE_SYNC).
      
      And the following have been left out for future extension:
      
       (7) Data version number: Could be used by userspace NFS servers [Aneesh
           Kumar].
      
           Can also be used to modify fill_post_wcc() in NFSD which retrieves
           i_version directly, but has just called vfs_getattr().  It could get
           it from the kstat struct if it used vfs_xgetattr() instead.
      
           (There's disagreement on the exact semantics of a single field, since
           not all filesystems do this the same way).
      
       (8) BSD stat compatibility: Including more fields from the BSD stat such
           as creation time (st_btime) and inode generation number (st_gen)
           [Jeremy Allison, Bernd Schubert].
      
       (9) Inode generation number: Useful for FUSE and userspace NFS servers
           [Bernd Schubert].
      
           (This was asked for but later deemed unnecessary with the
           open-by-handle capability available and caused disagreement as to
           whether it's a security hole or not).
      
      (10) Extra coherency data may be useful in making backups [Andreas Dilger].
      
           (No particular data were offered, but things like last backup
           timestamp, the data version number and the DOS archive bit would come
           into this category).
      
      (11) Allow the filesystem to indicate what it can/cannot provide: A
           filesystem can now say it doesn't support a standard stat feature if
           that isn't available, so if, for instance, inode numbers or UIDs don't
           exist or are fabricated locally...
      
           (This requires a separate system call - I have an fsinfo() call idea
           for this).
      
      (12) Store a 16-byte volume ID in the superblock that can be returned in
           struct xstat [Steve French].
      
           (Deferred to fsinfo).
      
      (13) Include granularity fields in the time data to indicate the
           granularity of each of the times (NFSv4 time_delta) [Steve French].
      
           (Deferred to fsinfo).
      
      (14) FS_IOC_GETFLAGS value.  These could be translated to BSD's st_flags.
           Note that the Linux IOC flags are a mess and filesystems such as Ext4
           define flags that aren't in linux/fs.h, so translation in the kernel
           may be a necessity (or, possibly, we provide the filesystem type too).
      
           (Some attributes are made available in stx_attributes, but the general
           feeling was that the IOC flags were to ext[234]-specific and shouldn't
           be exposed through statx this way).
      
      (15) Mask of features available on file (eg: ACLs, seclabel) [Brad Boyer,
           Michael Kerrisk].
      
           (Deferred, probably to fsinfo.  Finding out if there's an ACL or
           seclabal might require extra filesystem operations).
      
      (16) Femtosecond-resolution timestamps [Dave Chinner].
      
           (A __reserved field has been left in the statx_timestamp struct for
           this - if there proves to be a need).
      
      (17) A set multiple attributes syscall to go with this.
      
      ===============
      NEW SYSTEM CALL
      ===============
      
      The new system call is:
      
      	int ret = statx(int dfd,
      			const char *filename,
      			unsigned int flags,
      			unsigned int mask,
      			struct statx *buffer);
      
      The dfd, filename and flags parameters indicate the file to query, in a
      similar way to fstatat().  There is no equivalent of lstat() as that can be
      emulated with statx() by passing AT_SYMLINK_NOFOLLOW in flags.  There is
      also no equivalent of fstat() as that can be emulated by passing a NULL
      filename to statx() with the fd of interest in dfd.
      
      Whether or not statx() synchronises the attributes with the backing store
      can be controlled by OR'ing a value into the flags argument (this typically
      only affects network filesystems):
      
       (1) AT_STATX_SYNC_AS_STAT tells statx() to behave as stat() does in this
           respect.
      
       (2) AT_STATX_FORCE_SYNC will require a network filesystem to synchronise
           its attributes with the server - which might require data writeback to
           occur to get the timestamps correct.
      
       (3) AT_STATX_DONT_SYNC will suppress synchronisation with the server in a
           network filesystem.  The resulting values should be considered
           approximate.
      
      mask is a bitmask indicating the fields in struct statx that are of
      interest to the caller.  The user should set this to STATX_BASIC_STATS to
      get the basic set returned by stat().  It should be noted that asking for
      more information may entail extra I/O operations.
      
      buffer points to the destination for the data.  This must be 256 bytes in
      size.
      
      ======================
      MAIN ATTRIBUTES RECORD
      ======================
      
      The following structures are defined in which to return the main attribute
      set:
      
      	struct statx_timestamp {
      		__s64	tv_sec;
      		__s32	tv_nsec;
      		__s32	__reserved;
      	};
      
      	struct statx {
      		__u32	stx_mask;
      		__u32	stx_blksize;
      		__u64	stx_attributes;
      		__u32	stx_nlink;
      		__u32	stx_uid;
      		__u32	stx_gid;
      		__u16	stx_mode;
      		__u16	__spare0[1];
      		__u64	stx_ino;
      		__u64	stx_size;
      		__u64	stx_blocks;
      		__u64	__spare1[1];
      		struct statx_timestamp	stx_atime;
      		struct statx_timestamp	stx_btime;
      		struct statx_timestamp	stx_ctime;
      		struct statx_timestamp	stx_mtime;
      		__u32	stx_rdev_major;
      		__u32	stx_rdev_minor;
      		__u32	stx_dev_major;
      		__u32	stx_dev_minor;
      		__u64	__spare2[14];
      	};
      
      The defined bits in request_mask and stx_mask are:
      
      	STATX_TYPE		Want/got stx_mode & S_IFMT
      	STATX_MODE		Want/got stx_mode & ~S_IFMT
      	STATX_NLINK		Want/got stx_nlink
      	STATX_UID		Want/got stx_uid
      	STATX_GID		Want/got stx_gid
      	STATX_ATIME		Want/got stx_atime{,_ns}
      	STATX_MTIME		Want/got stx_mtime{,_ns}
      	STATX_CTIME		Want/got stx_ctime{,_ns}
      	STATX_INO		Want/got stx_ino
      	STATX_SIZE		Want/got stx_size
      	STATX_BLOCKS		Want/got stx_blocks
      	STATX_BASIC_STATS	[The stuff in the normal stat struct]
      	STATX_BTIME		Want/got stx_btime{,_ns}
      	STATX_ALL		[All currently available stuff]
      
      stx_btime is the file creation time, stx_mask is a bitmask indicating the
      data provided and __spares*[] are where as-yet undefined fields can be
      placed.
      
      Time fields are structures with separate seconds and nanoseconds fields
      plus a reserved field in case we want to add even finer resolution.  Note
      that times will be negative if before 1970; in such a case, the nanosecond
      fields will also be negative if not zero.
      
      The bits defined in the stx_attributes field convey information about a
      file, how it is accessed, where it is and what it does.  The following
      attributes map to FS_*_FL flags and are the same numerical value:
      
      	STATX_ATTR_COMPRESSED		File is compressed by the fs
      	STATX_ATTR_IMMUTABLE		File is marked immutable
      	STATX_ATTR_APPEND		File is append-only
      	STATX_ATTR_NODUMP		File is not to be dumped
      	STATX_ATTR_ENCRYPTED		File requires key to decrypt in fs
      
      Within the kernel, the supported flags are listed by:
      
      	KSTAT_ATTR_FS_IOC_FLAGS
      
      [Are any other IOC flags of sufficient general interest to be exposed
      through this interface?]
      
      New flags include:
      
      	STATX_ATTR_AUTOMOUNT		Object is an automount trigger
      
      These are for the use of GUI tools that might want to mark files specially,
      depending on what they are.
      
      Fields in struct statx come in a number of classes:
      
       (0) stx_dev_*, stx_blksize.
      
           These are local system information and are always available.
      
       (1) stx_mode, stx_nlinks, stx_uid, stx_gid, stx_[amc]time, stx_ino,
           stx_size, stx_blocks.
      
           These will be returned whether the caller asks for them or not.  The
           corresponding bits in stx_mask will be set to indicate whether they
           actually have valid values.
      
           If the caller didn't ask for them, then they may be approximated.  For
           example, NFS won't waste any time updating them from the server,
           unless as a byproduct of updating something requested.
      
           If the values don't actually exist for the underlying object (such as
           UID or GID on a DOS file), then the bit won't be set in the stx_mask,
           even if the caller asked for the value.  In such a case, the returned
           value will be a fabrication.
      
           Note that there are instances where the type might not be valid, for
           instance Windows reparse points.
      
       (2) stx_rdev_*.
      
           This will be set only if stx_mode indicates we're looking at a
           blockdev or a chardev, otherwise will be 0.
      
       (3) stx_btime.
      
           Similar to (1), except this will be set to 0 if it doesn't exist.
      
      =======
      TESTING
      =======
      
      The following test program can be used to test the statx system call:
      
      	samples/statx/test-statx.c
      
      Just compile and run, passing it paths to the files you want to examine.
      The file is built automatically if CONFIG_SAMPLES is enabled.
      
      Here's some example output.  Firstly, an NFS directory that crosses to
      another FSID.  Note that the AUTOMOUNT attribute is set because transiting
      this directory will cause d_automount to be invoked by the VFS.
      
      	[root@andromeda ~]# /tmp/test-statx -A /warthog/data
      	statx(/warthog/data) = 0
      	results=7ff
      	  Size: 4096            Blocks: 8          IO Block: 1048576  directory
      	Device: 00:26           Inode: 1703937     Links: 125
      	Access: (3777/drwxrwxrwx)  Uid:     0   Gid:  4041
      	Access: 2016-11-24 09:02:12.219699527+0000
      	Modify: 2016-11-17 10:44:36.225653653+0000
      	Change: 2016-11-17 10:44:36.225653653+0000
      	Attributes: 0000000000001000 (-------- -------- -------- -------- -------- -------- ---m---- --------)
      
      Secondly, the result of automounting on that directory.
      
      	[root@andromeda ~]# /tmp/test-statx /warthog/data
      	statx(/warthog/data) = 0
      	results=7ff
      	  Size: 4096            Blocks: 8          IO Block: 1048576  directory
      	Device: 00:27           Inode: 2           Links: 125
      	Access: (3777/drwxrwxrwx)  Uid:     0   Gid:  4041
      	Access: 2016-11-24 09:02:12.219699527+0000
      	Modify: 2016-11-17 10:44:36.225653653+0000
      	Change: 2016-11-17 10:44:36.225653653+0000
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      a528d35e
    • I
      sched/headers: Clean up <linux/sched.h> · 5eca1c10
      Ingo Molnar 提交于
      Now that <linux/sched.h> dependencies have been sorted out,
      do various trivial cleanups:
      
       - remove unnecessary structure predeclarations
       - fix various typos
       - update comments where necessary
       - remove pointless comments
       - use consistent types
       - tabulate consistently
       - use a consistent comment style
       - clean up the header section a bit
       - use a consistent style of a single field per line
       - remove line-breaks where they make the code look worse
       - etc ...
      
      No change in functionality.
      Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      5eca1c10
    • I
      sched/headers: Remove #ifdefs from <linux/sched.h> · 7f5f8e8d
      Ingo Molnar 提交于
      We can remove two pairs of #ifdefs by defining structures in a smarter way.
      Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      7f5f8e8d