1. 18 Aug, 2017 23 commits
    • Laura Abbott's avatar
      mm/vmalloc.c: don't unconditonally use __GFP_HIGHMEM · 704b862f
      Laura Abbott authored
      Commit 19809c2d ("mm, vmalloc: use __GFP_HIGHMEM implicitly") added
      use of __GFP_HIGHMEM for allocations.  vmalloc_32 may use
      GFP_DMA/GFP_DMA32 which does not play nice with __GFP_HIGHMEM and will
      trigger a BUG in gfp_zone.
      
      Only add __GFP_HIGHMEM if we aren't using GFP_DMA/GFP_DMA32.
      
      Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1482249
      Link: http://lkml.kernel.org/r/20170816220705.31374-1-labbott@redhat.com
      Fixes: 19809c2d ("mm, vmalloc: use __GFP_HIGHMEM implicitly")
      Signed-off-by: default avatarLaura Abbott <labbott@redhat.com>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      704b862f
    • zhong jiang's avatar
      mm/mempolicy: fix use after free when calling get_mempolicy · 73223e4e
      zhong jiang authored
      I hit a use after free issue when executing trinity and repoduced it
      with KASAN enabled.  The related call trace is as follows.
      
        BUG: KASan: use after free in SyS_get_mempolicy+0x3c8/0x960 at addr ffff8801f582d766
        Read of size 2 by task syz-executor1/798
      
        INFO: Allocated in mpol_new.part.2+0x74/0x160 age=3 cpu=1 pid=799
           __slab_alloc+0x768/0x970
           kmem_cache_alloc+0x2e7/0x450
           mpol_new.part.2+0x74/0x160
           mpol_new+0x66/0x80
           SyS_mbind+0x267/0x9f0
           system_call_fastpath+0x16/0x1b
        INFO: Freed in __mpol_put+0x2b/0x40 age=4 cpu=1 pid=799
           __slab_free+0x495/0x8e0
           kmem_cache_free+0x2f3/0x4c0
           __mpol_put+0x2b/0x40
           SyS_mbind+0x383/0x9f0
           system_call_fastpath+0x16/0x1b
        INFO: Slab 0xffffea0009cb8dc0 objects=23 used=8 fp=0xffff8801f582de40 flags=0x200000000004080
        INFO: Object 0xffff8801f582d760 @offset=5984 fp=0xffff8801f582d600
      
        Bytes b4 ffff8801f582d750: ae 01 ff ff 00 00 00 00 5a 5a 5a 5a 5a 5a 5a 5a  ........ZZZZZZZZ
        Object ffff8801f582d760: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
        Object ffff8801f582d770: 6b 6b 6b 6b 6b 6b 6b a5                          kkkkkkk.
        Redzone ffff8801f582d778: bb bb bb bb bb bb bb bb                          ........
        Padding ffff8801f582d8b8: 5a 5a 5a 5a 5a 5a 5a 5a                          ZZZZZZZZ
        Memory state around the buggy address:
        ffff8801f582d600: fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc
        ffff8801f582d680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
        >ffff8801f582d700: fc fc fc fc fc fc fc fc fc fc fc fc fb fb fb fc
      
      !shared memory policy is not protected against parallel removal by other
      thread which is normally protected by the mmap_sem.  do_get_mempolicy,
      however, drops the lock midway while we can still access it later.
      
      Early premature up_read is a historical artifact from times when
      put_user was called in this path see https://lwn.net/Articles/124754/
      but that is gone since 8bccd85f ("[PATCH] Implement sys_* do_*
      layering in the memory policy layer.").  but when we have the the
      current mempolicy ref count model.  The issue was introduced
      accordingly.
      
      Fix the issue by removing the premature release.
      
      Link: http://lkml.kernel.org/r/1502950924-27521-1-git-send-email-zhongjiang@huawei.comSigned-off-by: default avatarzhong jiang <zhongjiang@huawei.com>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Cc: Minchan Kim <minchan@kernel.org>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Mel Gorman <mgorman@techsingularity.net>
      Cc: <stable@vger.kernel.org>	[2.6+]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      73223e4e
    • Prakash Gupta's avatar
      mm/cma_debug.c: fix stack corruption due to sprintf usage · da094e42
      Prakash Gupta authored
      name[] in cma_debugfs_add_one() can only accommodate 16 chars including
      NULL to store sprintf output.  It's common for cma device name to be
      larger than 15 chars.  This can cause stack corrpution.  If the gcc
      stack protector is turned on, this can cause a panic due to stack
      corruption.
      
      Below is one example trace:
      
        Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in:
        ffffff8e69a75730
        Call trace:
           dump_backtrace+0x0/0x2c4
           show_stack+0x20/0x28
           dump_stack+0xb8/0xf4
           panic+0x154/0x2b0
           print_tainted+0x0/0xc0
           cma_debugfs_init+0x274/0x290
           do_one_initcall+0x5c/0x168
           kernel_init_freeable+0x1c8/0x280
      
      Fix the short sprintf buffer in cma_debugfs_add_one() by using
      scnprintf() instead of sprintf().
      
      Link: http://lkml.kernel.org/r/1502446217-21840-1-git-send-email-guptap@codeaurora.org
      Fixes: f318dd08 ("cma: Store a name in the cma structure")
      Signed-off-by: default avatarPrakash Gupta <guptap@codeaurora.org>
      Acked-by: default avatarLaura Abbott <labbott@redhat.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      da094e42
    • Jamie Iles's avatar
      signal: don't remove SIGNAL_UNKILLABLE for traced tasks. · eb61b591
      Jamie Iles authored
      When forcing a signal, SIGNAL_UNKILLABLE is removed to prevent recursive
      faults, but this is undesirable when tracing.  For example, debugging an
      init process (whether global or namespace), hitting a breakpoint and
      SIGTRAP will force SIGTRAP and then remove SIGNAL_UNKILLABLE.
      Everything continues fine, but then once debugging has finished, the
      init process is left killable which is unlikely what the user expects,
      resulting in either an accidentally killed init or an init that stops
      reaping zombies.
      
      Link: http://lkml.kernel.org/r/20170815112806.10728-1-jamie.iles@oracle.comSigned-off-by: default avatarJamie Iles <jamie.iles@oracle.com>
      Acked-by: default avatarOleg Nesterov <oleg@redhat.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      eb61b591
    • Michal Hocko's avatar
      mm, oom: fix potential data corruption when oom_reaper races with writer · 6b31d595
      Michal Hocko authored
      Wenwei Tao has noticed that our current assumption that the oom victim
      is dying and never doing any visible changes after it dies, and so the
      oom_reaper can tear it down, is not entirely true.
      
      __task_will_free_mem consider a task dying when SIGNAL_GROUP_EXIT is set
      but do_group_exit sends SIGKILL to all threads _after_ the flag is set.
      So there is a race window when some threads won't have
      fatal_signal_pending while the oom_reaper could start unmapping the
      address space.  Moreover some paths might not check for fatal signals
      before each PF/g-u-p/copy_from_user.
      
      We already have a protection for oom_reaper vs.  PF races by checking
      MMF_UNSTABLE.  This has been, however, checked only for kernel threads
      (use_mm users) which can outlive the oom victim.  A simple fix would be
      to extend the current check in handle_mm_fault for all tasks but that
      wouldn't be sufficient because the current check assumes that a kernel
      thread would bail out after EFAULT from get_user*/copy_from_user and
      never re-read the same address which would succeed because the PF path
      has established page tables already.  This seems to be the case for the
      only existing use_mm user currently (virtio driver) but it is rather
      fragile in general.
      
      This is even more fragile in general for more complex paths such as
      generic_perform_write which can re-read the same address more times
      (e.g.  iov_iter_copy_from_user_atomic to fail and then
      iov_iter_fault_in_readable on retry).
      
      Therefore we have to implement MMF_UNSTABLE protection in a robust way
      and never make a potentially corrupted content visible.  That requires
      to hook deeper into the PF path and check for the flag _every time_
      before a pte for anonymous memory is established (that means all
      !VM_SHARED mappings).
      
      The corruption can be triggered artificially
      (http://lkml.kernel.org/r/201708040646.v746kkhC024636@www262.sakura.ne.jp)
      but there doesn't seem to be any real life bug report.  The race window
      should be quite tight to trigger most of the time.
      
      Link: http://lkml.kernel.org/r/20170807113839.16695-3-mhocko@kernel.org
      Fixes: aac45363 ("mm, oom: introduce oom reaper")
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Reported-by: default avatarWenwei Tao <wenwei.tww@alibaba-inc.com>
      Tested-by: default avatarTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
      Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
      Cc: Andrea Argangeli <andrea@kernel.org>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      6b31d595
    • Michal Hocko's avatar
      mm: fix double mmap_sem unlock on MMF_UNSTABLE enforced SIGBUS · 5b53a6ea
      Michal Hocko authored
      Tetsuo Handa has noticed that MMF_UNSTABLE SIGBUS path in
      handle_mm_fault causes a lockdep splat
      
        Out of memory: Kill process 1056 (a.out) score 603 or sacrifice child
        Killed process 1056 (a.out) total-vm:4268108kB, anon-rss:2246048kB, file-rss:0kB, shmem-rss:0kB
        a.out (1169) used greatest stack depth: 11664 bytes left
        DEBUG_LOCKS_WARN_ON(depth <= 0)
        ------------[ cut here ]------------
        WARNING: CPU: 6 PID: 1339 at kernel/locking/lockdep.c:3617 lock_release+0x172/0x1e0
        CPU: 6 PID: 1339 Comm: a.out Not tainted 4.13.0-rc3-next-20170803+ #142
        Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/02/2015
        RIP: 0010:lock_release+0x172/0x1e0
        Call Trace:
           up_read+0x1a/0x40
           __do_page_fault+0x28e/0x4c0
           do_page_fault+0x30/0x80
           page_fault+0x28/0x30
      
      The reason is that the page fault path might have dropped the mmap_sem
      and returned with VM_FAULT_RETRY.  MMF_UNSTABLE check however rewrites
      the error path to VM_FAULT_SIGBUS and we always expect mmap_sem taken in
      that path.  Fix this by taking mmap_sem when VM_FAULT_RETRY is held in
      the MMF_UNSTABLE path.
      
      We cannot simply add VM_FAULT_SIGBUS to the existing error code because
      all arch specific page fault handlers and g-u-p would have to learn a
      new error code combination.
      
      Link: http://lkml.kernel.org/r/20170807113839.16695-2-mhocko@kernel.org
      Fixes: 3f70dc38 ("mm: make sure that kthreads will not refault oom reaped memory")
      Reported-by: default avatarTetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Acked-by: default avatarDavid Rientjes <rientjes@google.com>
      Cc: Andrea Argangeli <andrea@kernel.org>
      Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Wenwei Tao <wenwei.tww@alibaba-inc.com>
      Cc: <stable@vger.kernel.org>	[4.9+]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      5b53a6ea
    • Vladimir Davydov's avatar
      slub: fix per memcg cache leak on css offline · f6ba4880
      Vladimir Davydov authored
      To avoid a possible deadlock, sysfs_slab_remove() schedules an
      asynchronous work to delete sysfs entries corresponding to the kmem
      cache.  To ensure the cache isn't freed before the work function is
      called, it takes a reference to the cache kobject.  The reference is
      supposed to be released by the work function.
      
      However, the work function (sysfs_slab_remove_workfn()) does nothing in
      case the cache sysfs entry has already been deleted, leaking the kobject
      and the corresponding cache.
      
      This may happen on a per memcg cache destruction, because sysfs entries
      of a per memcg cache are deleted on memcg offline if the cache is empty
      (see __kmemcg_cache_deactivate()).
      
      The kmemleak report looks like this:
      
        unreferenced object 0xffff9f798a79f540 (size 32):
          comm "kworker/1:4", pid 15416, jiffies 4307432429 (age 28687.554s)
          hex dump (first 32 bytes):
            6b 6d 61 6c 6c 6f 63 2d 31 36 28 31 35 39 39 3a  kmalloc-16(1599:
            6e 65 77 72 6f 6f 74 29 00 23 6b c0 ff ff ff ff  newroot).#k.....
          backtrace:
             kmemleak_alloc+0x4a/0xa0
             __kmalloc_track_caller+0x148/0x2c0
             kvasprintf+0x66/0xd0
             kasprintf+0x49/0x70
             memcg_create_kmem_cache+0xe6/0x160
             memcg_kmem_cache_create_func+0x20/0x110
             process_one_work+0x205/0x5d0
             worker_thread+0x4e/0x3a0
             kthread+0x109/0x140
             ret_from_fork+0x2a/0x40
        unreferenced object 0xffff9f79b6136840 (size 416):
          comm "kworker/1:4", pid 15416, jiffies 4307432429 (age 28687.573s)
          hex dump (first 32 bytes):
            40 fb 80 c2 3e 33 00 00 00 00 00 40 00 00 00 00  @...>3.....@....
            00 00 00 00 00 00 00 00 10 00 00 00 10 00 00 00  ................
          backtrace:
             kmemleak_alloc+0x4a/0xa0
             kmem_cache_alloc+0x128/0x280
             create_cache+0x3b/0x1e0
             memcg_create_kmem_cache+0x118/0x160
             memcg_kmem_cache_create_func+0x20/0x110
             process_one_work+0x205/0x5d0
             worker_thread+0x4e/0x3a0
             kthread+0x109/0x140
             ret_from_fork+0x2a/0x40
      
      Fix the leak by adding the missing call to kobject_put() to
      sysfs_slab_remove_workfn().
      
      Link: http://lkml.kernel.org/r/20170812181134.25027-1-vdavydov.dev@gmail.com
      Fixes: 3b7b3140 ("slub: make sysfs file removal asynchronous")
      Signed-off-by: default avatarVladimir Davydov <vdavydov.dev@gmail.com>
      Reported-by: default avatarAndrei Vagin <avagin@gmail.com>
      Tested-by: default avatarAndrei Vagin <avagin@gmail.com>
      Acked-by: default avatarTejun Heo <tj@kernel.org>
      Acked-by: default avatarDavid Rientjes <rientjes@google.com>
      Cc: Michal Hocko <mhocko@kernel.org>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: Pekka Enberg <penberg@kernel.org>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: <stable@vger.kernel.org>	[4.12.x]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      f6ba4880
    • Pavel Tatashin's avatar
      mm: discard memblock data later · 3010f876
      Pavel Tatashin authored
      There is existing use after free bug when deferred struct pages are
      enabled:
      
      The memblock_add() allocates memory for the memory array if more than
      128 entries are needed.  See comment in e820__memblock_setup():
      
        * The bootstrap memblock region count maximum is 128 entries
        * (INIT_MEMBLOCK_REGIONS), but EFI might pass us more E820 entries
        * than that - so allow memblock resizing.
      
      This memblock memory is freed here:
              free_low_memory_core_early()
      
      We access the freed memblock.memory later in boot when deferred pages
      are initialized in this path:
      
              deferred_init_memmap()
                      for_each_mem_pfn_range()
                        __next_mem_pfn_range()
                          type = &memblock.memory;
      
      One possible explanation for why this use-after-free hasn't been hit
      before is that the limit of INIT_MEMBLOCK_REGIONS has never been
      exceeded at least on systems where deferred struct pages were enabled.
      
      Tested by reducing INIT_MEMBLOCK_REGIONS down to 4 from the current 128,
      and verifying in qemu that this code is getting excuted and that the
      freed pages are sane.
      
      Link: http://lkml.kernel.org/r/1502485554-318703-2-git-send-email-pasha.tatashin@oracle.com
      Fixes: 7e18adb4 ("mm: meminit: initialise remaining struct pages in parallel with kswapd")
      Signed-off-by: default avatarPavel Tatashin <pasha.tatashin@oracle.com>
      Reviewed-by: default avatarSteven Sistare <steven.sistare@oracle.com>
      Reviewed-by: default avatarDaniel Jordan <daniel.m.jordan@oracle.com>
      Reviewed-by: default avatarBob Picco <bob.picco@oracle.com>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Cc: Mel Gorman <mgorman@techsingularity.net>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      3010f876
    • Luis R. Rodriguez's avatar
      test_kmod: fix description for -s -and -c parameters · 768dc4e4
      Luis R. Rodriguez authored
      The descriptions were reversed, correct this.
      
      Link: http://lkml.kernel.org/r/20170809234635.13443-4-mcgrof@kernel.org
      Fixes: 64b67120 ("test_sysctl: add generic script to expand on tests")
      Signed-off-by: default avatarLuis R. Rodriguez <mcgrof@kernel.org>
      Reported-by: default avatarDaniel Mentz <danielmentz@google.com>
      Cc: "Eric W. Biederman" <ebiederm@xmission.com>
      Cc: Colin Ian King <colin.king@canonical.com>
      Cc: Dan Carpenter <dan.carpenter@oracle.com>
      Cc: David Binderman <dcb314@hotmail.com>
      Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Jessica Yu <jeyu@redhat.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Matt Redfearn <matt.redfearn@imgetc.com>
      Cc: Matt Redfearn <matt.redfearn@imgtec.com>
      Cc: Michal Marek <mmarek@suse.com>
      Cc: Miroslav Benes <mbenes@suse.cz>
      Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Petr Mladek <pmladek@suse.com>
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Cc: Shuah Khan <shuah@kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      768dc4e4
    • Luis R. Rodriguez's avatar
      kmod: fix wait on recursive loop · 2ba293c9
      Luis R. Rodriguez authored
      Recursive loops with module loading were previously handled in kmod by
      restricting the number of modprobe calls to 50 and if that limit was
      breached request_module() would return an error and a user would see the
      following on their kernel dmesg:
      
        request_module: runaway loop modprobe binfmt-464c
        Starting init:/sbin/init exists but couldn't execute it (error -8)
      
      This issue could happen for instance when a 64-bit kernel boots a 32-bit
      userspace on some architectures and has no 32-bit binary format
      hanlders.  This is visible, for instance, when a CONFIG_MODULES enabled
      64-bit MIPS kernel boots a into o32 root filesystem and the binfmt
      handler for o32 binaries is not built-in.
      
      After commit 6d7964a7 ("kmod: throttle kmod thread limit") we now
      don't have any visible signs of an error and the kernel just waits for
      the loop to end somehow.
      
      Although this *particular* recursive loop could also be addressed by
      doing a sanity check on search_binary_handler() and disallowing a
      modular binfmt to be required for modprobe, a generic solution for any
      recursive kernel kmod issues is still needed.
      
      This should catch these loops.  We can investigate each loop and address
      each one separately as they come in, this however puts a stop gap for
      them as before.
      
      Link: http://lkml.kernel.org/r/20170809234635.13443-3-mcgrof@kernel.org
      Fixes: 6d7964a7 ("kmod: throttle kmod thread limit")
      Signed-off-by: default avatarLuis R. Rodriguez <mcgrof@kernel.org>
      Reported-by: default avatarMatt Redfearn <matt.redfearn@imgtec.com>
      Tested-by: default avatarMatt Redfearn <matt.redfearn@imgetc.com>
      Cc: "Eric W. Biederman" <ebiederm@xmission.com>
      Cc: Colin Ian King <colin.king@canonical.com>
      Cc: Dan Carpenter <dan.carpenter@oracle.com>
      Cc: Daniel Mentz <danielmentz@google.com>
      Cc: David Binderman <dcb314@hotmail.com>
      Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Jessica Yu <jeyu@redhat.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Michal Marek <mmarek@suse.com>
      Cc: Miroslav Benes <mbenes@suse.cz>
      Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Petr Mladek <pmladek@suse.com>
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Cc: Shuah Khan <shuah@kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      2ba293c9
    • Luis R. Rodriguez's avatar
      wait: add wait_event_killable_timeout() · 8ada9279
      Luis R. Rodriguez authored
      These are the few pending fixes I have queued up for v4.13-final.  One
      is a a generic regression fix for recursive loops on kmod and the other
      one is a trivial print out correction.
      
      During the v4.13 development we assumed that recursive kmod loops were
      no longer possible.  Clearly that is not true.  The regression fix makes
      use of a new killable wait.  We use a killable wait to be paranoid in
      how signals might be sent to modprobe and only accept a proper SIGKILL.
      The signal will only be available to userspace to issue *iff* a thread
      has already entered a wait state, and that happens only if we've already
      throttled after 50 kmod threads have been hit.
      
      Note that although it may seem excessive to trigger a failure afer 5
      seconds if all kmod thread remain busy, prior to the series of changes
      that went into v4.13 we would actually *always* fatally fail any request
      which came in if the limit was already reached.  The new waiting
      implemented in v4.13 actually gives us *more* breathing room -- the wait
      for 5 seconds is a wait for *any* kmod thread to finish.  We give up and
      fail *iff* no kmod thread has finished and they're *all* running
      straight for 5 consecutive seconds.  If 50 kmod threads are running
      consecutively for 5 seconds something else must be really bad.
      
      Recursive loops with kmod are bad but they're also hard to implement
      properly as a selftest without currently fooling current userspace tools
      like kmod [1].  For instance kmod will complain when you run depmod if
      it finds a recursive loop with symbol dependency between modules as such
      this type of recursive loop cannot go upstream as the modules_install
      target will fail after running depmod.
      
      These tests already exist on userspace kmod upstream though (refer to
      the testsuite/module-playground/mod-loop-*.c files).  The same is not
      true if request_module() is used though, or worst if aliases are used.
      
      Likewise the issue with 64-bit kernels booting 32-bit userspace without
      a binfmt handler built-in is also currently not detected and proactively
      avoided by userspace kmod tools, or kconfig for all architectures.
      Although we could complain in the kernel when some of these individual
      recursive issues creep up, proactively avoiding these situations in
      userspace at build time is what we should keep striving for.
      
      Lastly, since recursive loops could happen with kmod it may mean
      recursive loops may also be possible with other kernel usermode helpers,
      this should be investigated and long term if we can come up with a more
      sensible generic solution even better!
      
      [0] https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux.git/log/?h=20170809-kmod-for-v4.13-final
      [1] https://git.kernel.org/pub/scm/utils/kernel/kmod/kmod.git
      
      This patch (of 3):
      
      This wait is similar to wait_event_interruptible_timeout() but only
      accepts SIGKILL interrupt signal.  Other signals are ignored.
      
      Link: http://lkml.kernel.org/r/20170809234635.13443-2-mcgrof@kernel.orgSigned-off-by: default avatarLuis R. Rodriguez <mcgrof@kernel.org>
      Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
      Cc: Jessica Yu <jeyu@redhat.com>
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Cc: Michal Marek <mmarek@suse.com>
      Cc: Petr Mladek <pmladek@suse.com>
      Cc: Miroslav Benes <mbenes@suse.cz>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: "Eric W. Biederman" <ebiederm@xmission.com>
      Cc: Shuah Khan <shuah@kernel.org>
      Cc: Matt Redfearn <matt.redfearn@imgtec.com>
      Cc: Dan Carpenter <dan.carpenter@oracle.com>
      Cc: Colin Ian King <colin.king@canonical.com>
      Cc: Daniel Mentz <danielmentz@google.com>
      Cc: David Binderman <dcb314@hotmail.com>
      Cc: Matt Redfearn <matt.redfearn@imgetc.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      8ada9279
    • Nicholas Piggin's avatar
      kernel/watchdog: fix Kconfig constraints for perf hardlockup watchdog · 92e5aae4
      Nicholas Piggin authored
      Commit 05a4a952 ("kernel/watchdog: split up config options") lost
      the perf-based hardlockup detector's dependency on PERF_EVENTS, which
      can result in broken builds with some powerpc configurations.
      
      Restore the dependency.  Add it in for x86 too, despite x86 always
      selecting PERF_EVENTS it seems reasonable to make the dependency
      explicit.
      
      Link: http://lkml.kernel.org/r/20170810114452.6673-1-npiggin@gmail.com
      Fixes: 05a4a952 ("kernel/watchdog: split up config options")
      Signed-off-by: default avatarNicholas Piggin <npiggin@gmail.com>
      Acked-by: default avatarDon Zickus <dzickus@redhat.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      92e5aae4
    • Johannes Weiner's avatar
      mm: memcontrol: fix NULL pointer crash in test_clear_page_writeback() · 739f79fc
      Johannes Weiner authored
      Jaegeuk and Brad report a NULL pointer crash when writeback ending tries
      to update the memcg stats:
      
          BUG: unable to handle kernel NULL pointer dereference at 00000000000003b0
          IP: test_clear_page_writeback+0x12e/0x2c0
          [...]
          RIP: 0010:test_clear_page_writeback+0x12e/0x2c0
          Call Trace:
           <IRQ>
           end_page_writeback+0x47/0x70
           f2fs_write_end_io+0x76/0x180 [f2fs]
           bio_endio+0x9f/0x120
           blk_update_request+0xa8/0x2f0
           scsi_end_request+0x39/0x1d0
           scsi_io_completion+0x211/0x690
           scsi_finish_command+0xd9/0x120
           scsi_softirq_done+0x127/0x150
           __blk_mq_complete_request_remote+0x13/0x20
           flush_smp_call_function_queue+0x56/0x110
           generic_smp_call_function_single_interrupt+0x13/0x30
           smp_call_function_single_interrupt+0x27/0x40
           call_function_single_interrupt+0x89/0x90
          RIP: 0010:native_safe_halt+0x6/0x10
      
          (gdb) l *(test_clear_page_writeback+0x12e)
          0xffffffff811bae3e is in test_clear_page_writeback (./include/linux/memcontrol.h:619).
          614		mod_node_page_state(page_pgdat(page), idx, val);
          615		if (mem_cgroup_disabled() || !page->mem_cgroup)
          616			return;
          617		mod_memcg_state(page->mem_cgroup, idx, val);
          618		pn = page->mem_cgroup->nodeinfo[page_to_nid(page)];
          619		this_cpu_add(pn->lruvec_stat->count[idx], val);
          620	}
          621
          622	unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
          623							gfp_t gfp_mask,
      
      The issue is that writeback doesn't hold a page reference and the page
      might get freed after PG_writeback is cleared (and the mapping is
      unlocked) in test_clear_page_writeback().  The stat functions looking up
      the page's node or zone are safe, as those attributes are static across
      allocation and free cycles.  But page->mem_cgroup is not, and it will
      get cleared if we race with truncation or migration.
      
      It appears this race window has been around for a while, but less likely
      to trigger when the memcg stats were updated first thing after
      PG_writeback is cleared.  Recent changes reshuffled this code to update
      the global node stats before the memcg ones, though, stretching the race
      window out to an extent where people can reproduce the problem.
      
      Update test_clear_page_writeback() to look up and pin page->mem_cgroup
      before clearing PG_writeback, then not use that pointer afterward.  It
      is a partial revert of 62cccb8c ("mm: simplify lock_page_memcg()")
      but leaves the pageref-holding callsites that aren't affected alone.
      
      Link: http://lkml.kernel.org/r/20170809183825.GA26387@cmpxchg.org
      Fixes: 62cccb8c ("mm: simplify lock_page_memcg()")
      Signed-off-by: default avatarJohannes Weiner <hannes@cmpxchg.org>
      Reported-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
      Tested-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
      Reported-by: default avatarBradley Bolen <bradleybolen@gmail.com>
      Tested-by: default avatarBrad Bolen <bradleybolen@gmail.com>
      Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
      Cc: Michal Hocko <mhocko@suse.cz>
      Cc: <stable@vger.kernel.org>	[4.6+]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      739f79fc
    • Linus Torvalds's avatar
      Merge tag 'powerpc-4.13-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux · 039a8e38
      Linus Torvalds authored
      Pull powerpc fixes from Michael Ellerman:
       "A bug in the VSX register saving that could cause userspace FP/VMX
        register corruption.
      
        Never seen to happen (that we know of), was found by code inspection,
        but still tagged for stable given the consequences"
      
      * tag 'powerpc-4.13-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
        powerpc: Fix VSX enabling/flushing to also test MSR_FP and MSR_VEC
      039a8e38
    • Linus Torvalds's avatar
      Merge tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc · 42833468
      Linus Torvalds authored
      Pull ARM SoC fixes from Arnd Bergmann:
       "A small number of bugfixes, nothing serious this time. Here is a full
        list.
      
        4.13 regression fix:
      
         - imx7d-sdb pinctrl support regressed in 4.13 due to an incomplete
           patch
      
        DT fixes for recently added devices:
      
         - badly copied DT entries on imx6qdl-nitrogen6_som broke PCI reset
      
         - sama5d2 memory controller had the wrong ID and registers
      
         - imx7 power domains did not work correctly with deferred probing
           (driver added in 4.12)
      
         - Allwinner H5 pinctrl (added in 4.12) did not work right with GPIO
           interrupts
      
        Fixes for older bugs that just got noticed:
      
         - i.MX25 ADC support (added in 4.6) apparently never worked right due
           to a missing 'ranges' property in DT.
      
         - Renesas Salvador Audio support (added in v4.5) was broken for
           device repeated bind/unbind due to a naming conflict.
      
         - Various allwinner boards are missing an 'ethernet' alias in DT,
           leading to unstable device naming.
      
        Preventive bugfix:
      
         - TI Keystone needs a fix to prevent a NULL pointer dereference with
           an upcoming PM change"
      
      * tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
        soc: ti: ti_sci_pm_domains: Populate name for genpd
        ARM: dts: imx6qdl-nitrogen6_som2: fix PCIe reset
        arm64: allwinner: h5: fix pinctrl IRQs
        arm64: allwinner: a64: sopine: add missing ethernet0 alias
        arm64: allwinner: a64: pine64: add missing ethernet0 alias
        arm64: allwinner: a64: bananapi-m64: add missing ethernet0 alias
        arm64: renesas: salvator-common: avoid audio_clkout naming conflict
        ARM: dts: i.MX25: add ranges to tscadc
        soc: imx: gpcv2: fix regulator deferred probe
        ARM: dts: at91: sama5d2: fix EBI/NAND controllers declaration
        ARM: dts: at91: sama5d2: use sama5d2 compatible string for SMC
        ARM: dts: imx7d-sdb: Put pinctrl_spi4 in the correct location
      42833468
    • Linus Torvalds's avatar
      Merge tag 'sound-4.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound · cb247857
      Linus Torvalds authored
      Pull sound fixes from Takashi Iwai:
       "A collection of small fixes, mostly for regression fixes (sequencer
        kconfig and emu10k1 probe) and device-specific quirks (three for USB
        and one for HD-audio).
      
        One significant change is a fix for races in ALSA sequencer core,
        which covers over the previous incomplete fix"
      
      * tag 'sound-4.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
        ALSA: emu10k1: Fix forgotten user-copy conversion in init code
        ALSA: usb-audio: add DSD support for new Amanero PID
        ALSA: usb-audio: Add mute TLV for playback volumes on C-Media devices
        ALSA: usb-audio: Apply sample rate quirk to Sennheiser headset
        ALSA: seq: 2nd attempt at fixing race creating a queue
        ALSA: hda/realtek - Fix pincfg for Dell XPS 13 9370
        ALSA: seq: Fix CONFIG_SND_SEQ_MIDI dependency
      cb247857
    • Linus Torvalds's avatar
      Merge tag 'dma-mapping-4.13-3' of git://git.infradead.org/users/hch/dma-mapping · 4478976a
      Linus Torvalds authored
      Pull dma-mapping fix from Christoph Hellwig:
       "Another dma-mapping regression fix"
      
      * tag 'dma-mapping-4.13-3' of git://git.infradead.org/users/hch/dma-mapping:
        of: fix DMA mask generation
      4478976a
    • Dave Gerlach's avatar
      soc: ti: ti_sci_pm_domains: Populate name for genpd · 4dd6a997
      Dave Gerlach authored
      Commit b6a1d093 ("PM / Domains: Extend generic power domain
      debugfs") now creates a debugfs directory for each genpd based on the
      name of the genpd. Currently no name is given to the genpd created by
      ti_sci_pm_domains driver so because of this we see a NULL pointer
      dereferences when it is accessed on boot when the debugfs entry creation
      is attempted.
      
      Give the genpd a name before registering it to avoid this.
      
      Fixes: 52835d59 ("soc: ti: Add ti_sci_pm_domains driver")
      Signed-off-by: default avatarDave Gerlach <d-gerlach@ti.com>
      Signed-off-by: default avatarSantosh Shilimkar <ssantosh@kernel.org>
      Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
      4dd6a997
    • Arnd Bergmann's avatar
      Merge tag 'imx-fixes-4.13-3' of... · 93112486
      Arnd Bergmann authored
      Merge tag 'imx-fixes-4.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux into fixes
      
      Pull "i.MX fixes for 4.13, round 3" from Shawn Guo:
      
       - Fix PCIe reset GPIO of imx6qdl-nitrogen6_som2 board, which was
         a bad copy from nitrogen6_max device tree.
      
      * tag 'imx-fixes-4.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux:
        ARM: dts: imx6qdl-nitrogen6_som2: fix PCIe reset
      93112486
    • Arnd Bergmann's avatar
      Merge tag 'sunxi-fixes-for-4.13-2' of... · 552c497c
      Arnd Bergmann authored
      Merge tag 'sunxi-fixes-for-4.13-2' of https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux into fixes
      
      Pull "Allwinner fixes for 4.13, round 2" from Chen-Yu Tsai:
      
      Three fixes adding a missing alias for the Ethernet controller on A64
      boards. One adding a missing interrupt for the pin controller.
      
      * tag 'sunxi-fixes-for-4.13-2' of https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux:
        arm64: allwinner: h5: fix pinctrl IRQs
        arm64: allwinner: a64: sopine: add missing ethernet0 alias
        arm64: allwinner: a64: pine64: add missing ethernet0 alias
        arm64: allwinner: a64: bananapi-m64: add missing ethernet0 alias
      552c497c
    • Takashi Iwai's avatar
      ALSA: emu10k1: Fix forgotten user-copy conversion in init code · 0b36f2bd
      Takashi Iwai authored
      The commit d42fe63d ("ALSA: emu10k1: Get rid of set_fs() usage")
      converted the user-space copy hack with set_fs() to the direct
      memcpy(), but one place was forgotten.  This resulted in the error
      from snd_emu10k1_init_efx(), eventually failed to load the driver.
      Fix the missing piece.
      
      Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196687
      Fixes: d42fe63d ("ALSA: emu10k1: Get rid of set_fs() usage")
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      0b36f2bd
    • Jussi Laako's avatar
      ALSA: usb-audio: add DSD support for new Amanero PID · ed993c6f
      Jussi Laako authored
      Add DSD support for new Amanero Combo384 firmware version with a new
      PID. This firmware uses DSD_U32_BE.
      
      Fixes: 3eff682d ("ALSA: usb-audio: Support both DSD LE/BE Amanero firmware versions")
      Signed-off-by: default avatarJussi Laako <jussi@sonarnerd.net>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      ed993c6f
    • Gary Bisson's avatar
      ARM: dts: imx6qdl-nitrogen6_som2: fix PCIe reset · c40bc54f
      Gary Bisson authored
      Previous value was a bad copy of nitrogen6_max device tree.
      Signed-off-by: default avatarGary Bisson <gary.bisson@boundarydevices.com>
      Fixes: 3faa1bb2 ("ARM: dts: imx: add Boundary Devices Nitrogen6_SOM2 support")
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarShawn Guo <shawnguo@kernel.org>
      c40bc54f
  2. 17 Aug, 2017 13 commits
    • Linus Torvalds's avatar
      Merge tag 'drm-fixes-for-v4.13-rc6' of git://people.freedesktop.org/~airlied/linux · 04d49f36
      Linus Torvalds authored
      Pull drm fixes from Dave Airlie:
       "Seems to be slowing down nicely, just one amdgpu fix, and a bunch of
        i915 fixes"
      
      * tag 'drm-fixes-for-v4.13-rc6' of git://people.freedesktop.org/~airlied/linux:
        drm/amdgpu: save list length when fence is signaled
        drm/i915: Avoid the gpu reset vs. modeset deadlock
        drm/i915: Suppress switch_mm emission between the same aliasing_ppgtt
        drm/i915: Return correct EDP voltage swing table for 0.85V
        drm/i915/cnl: Add slice and subslice information to debugfs.
        drm/i915: Perform an invalidate prior to executing golden renderstate
        drm/i915: remove unused function declaration
      04d49f36
    • Linus Torvalds's avatar
      Merge tag 'pm-4.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm · d33a2a91
      Linus Torvalds authored
      Pull power management fixes from Rafael Wysocki:
       "These fix two issues related to exposing the current CPU frequency to
        user space on x86.
      
        Specifics:
      
         - Disable interrupts around reading IA32_APERF and IA32_MPERF in
           aperfmperf_snapshot_khz() (introduced recently) to avoid excessive
           delays between the reads that may result from interrupt handling
           (Doug Smythies).
      
         - Fix the computation of the CPU frequency to be reported through the
           pstate_sample tracepoint in intel_pstate (Doug Smythies)"
      
      * tag 'pm-4.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
        cpufreq: x86: Disable interrupts during MSRs reading
        cpufreq: intel_pstate: report correct CPU frequencies during trace
      d33a2a91
    • Linus Torvalds's avatar
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input · 440105d3
      Linus Torvalds authored
      Pull input fixes from Dmitry Torokhov.
      
      * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
        Input: elan_i2c - Add antoher Lenovo ACPI ID for upcoming Lenovo NB
        Input: elan_i2c - add ELAN0608 to the ACPI table
        Input: trackpoint - assume 3 buttons when buttons detection fails
      440105d3
    • Dave Airlie's avatar
      Merge branch 'drm-fixes-4.13' of git://people.freedesktop.org/~agd5f/linux into drm-fixes · 28eb4628
      Dave Airlie authored
      single amdgpu fix.
      
      * 'drm-fixes-4.13' of git://people.freedesktop.org/~agd5f/linux:
        drm/amdgpu: save list length when fence is signaled
      28eb4628
    • Dave Airlie's avatar
      Merge tag 'drm-intel-fixes-2017-08-16' of... · 41d31b5f
      Dave Airlie authored
      Merge tag 'drm-intel-fixes-2017-08-16' of git://anongit.freedesktop.org/git/drm-intel into drm-fixes
      
      drm/i915 fixes for v4.13-rc6
      
      "Chris' "drm/i915: Perform an invalidate prior to executing golden renderstate" and Daniel's
      "drm/i915: Avoid the gpu reset vs. modeset deadlock" seem like the most important ones.
      
      * tag 'drm-intel-fixes-2017-08-16' of git://anongit.freedesktop.org/git/drm-intel:
        drm/i915: Avoid the gpu reset vs. modeset deadlock
        drm/i915: Suppress switch_mm emission between the same aliasing_ppgtt
        drm/i915: Return correct EDP voltage swing table for 0.85V
        drm/i915/cnl: Add slice and subslice information to debugfs.
        drm/i915: Perform an invalidate prior to executing golden renderstate
        drm/i915: remove unused function declaration
      41d31b5f
    • Rafael J. Wysocki's avatar
      Merge branches 'intel_pstate-fix' and 'cpufreq-x86-fix' · 8179962b
      Rafael J. Wysocki authored
      * intel_pstate-fix:
        cpufreq: intel_pstate: report correct CPU frequencies during trace
      
      * cpufreq-x86-fix:
        cpufreq: x86: Disable interrupts during MSRs reading
      8179962b
    • Linus Torvalds's avatar
      Merge branch 'parisc-4.13-5' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux · 3bc6c906
      Linus Torvalds authored
      Pull parisc fixes from Helge Deller:
      
       - Fix PCI memory bar assignments with 64-bit kernels on machines with
         Dino/Cujo PCI chipsets. This makes PCI graphic cards work on such
         machines (from Thomas Bogendoerfer).
      
       - Fix documentation to be more clear about the difference between %pF
         and %pS printk format usage. There are still many places in the
         kernel which have it wrong (from Petr Mladek, Sergey Senozhatsky &
         me).
      
      * 'parisc-4.13-5' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
        printk-formats.txt: Better describe the difference between %pS and %pF
        parisc: pci memory bar assignment fails with 64bit kernels on dino/cujo
      3bc6c906
    • Linus Torvalds's avatar
      Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs · 99f781b1
      Linus Torvalds authored
      Pull quota fix from Jan Kara:
       "A fix of a check for quota limit"
      
      * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
        quota: correct space limit check
      99f781b1
    • Linus Torvalds's avatar
      pty: fix the cached path of the pty slave file descriptor in the master · c8c03f18
      Linus Torvalds authored
      Christian Brauner reported that if you use the TIOCGPTPEER ioctl() to
      get a slave pty file descriptor, the resulting file descriptor doesn't
      look right in /proc/<pid>/fd/<fd>.  In particular, he wanted to use
      readlink() on /proc/self/fd/<fd> to get the pathname of the slave pty
      (basically implementing "ptsname{_r}()").
      
      The reason for that was that we had generated the wrong 'struct path'
      when we create the pty in ptmx_open().
      
      In particular, the dentry was correct, but the vfsmount pointed to the
      mount of the ptmx node. That _can_ be correct - in case you use
      "/dev/pts/ptmx" to open the master - but usually is not.  The normal
      case is to use /dev/ptmx, which then looks up the pts/ directory, and
      then the vfsmount of the ptmx node is obviously the /dev directory, not
      the /dev/pts/ directory.
      
      We actually did have the right vfsmount available, but in the wrong
      place (it gets looked up in 'devpts_acquire()' when we get a reference
      to the pts filesystem), and so ptmx_open() used the wrong mnt pointer.
      
      The end result of this confusion was that the pty worked fine, but when
      if you did TIOCGPTPEER to get the slave side of the pty, end end result
      would also work, but have that dodgy 'struct path'.
      
      And then when doing "d_path()" on to get the pathname, the vfsmount
      would not match the root of the pts directory, and d_path() would return
      an empty pathname thinking that the entry had escaped a bind mount into
      another mount.
      
      This fixes the problem by making devpts_acquire() return the vfsmount
      for the pts filesystem, allowing ptmx_open() to trivially just use the
      right mount for the pts dentry, and create the proper 'struct path'.
      Reported-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Acked-by: default avatarEric Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      c8c03f18
    • Takashi Iwai's avatar
      ALSA: usb-audio: Add mute TLV for playback volumes on C-Media devices · 0f174b35
      Takashi Iwai authored
      C-Media devices (at least some models) mute the playback stream when
      volumes are set to the minimum value.  But this isn't informed via TLV
      and the user-space, typically PulseAudio, gets confused as if it's
      still played in a low volume.
      
      This patch adds the new flag, min_mute, to struct usb_mixer_elem_info
      for indicating that the mixer element is with the minimum-mute volume.
      This flag is set for known C-Media devices in
      snd_usb_mixer_fu_apply_quirk() in turn.
      
      Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196669
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      0f174b35
    • Arnd Bergmann's avatar
      Merge tag 'renesas-fixes4-for-v4.13' of... · 872784bf
      Arnd Bergmann authored
      Merge tag 'renesas-fixes4-for-v4.13' of https://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas into fixes
      
      Pull "Fourth Round of Renesas ARM Based SoC Fixes for v4.13" from Simon Horman:
      
      * Avoid audio_clkout naming conflict for salvator boards using
        Renesas R-Car Gen 3 SoCs
      
        Morimoto-san says "The clock name of "audio_clkout" is used by the
        Renesas sound driver.  This duplicated naming breaks its clock
        registering/unregistering.  Especially when unbind/bind it can't handle
        clkout correctly.  This patch renames "audio_clkout" to "audio-clkout" to
        avoid the naming conflict."
      
      * tag 'renesas-fixes4-for-v4.13' of https://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas:
        arm64: renesas: salvator-common: avoid audio_clkout naming conflict
      872784bf
    • Robin Murphy's avatar
      of: fix DMA mask generation · ee7b1f31
      Robin Murphy authored
      Historically, DMA masks have suffered some ambiguity between whether
      they represent the range of physical memory a device can access, or the
      address bits a device is capable of driving, particularly since on many
      platforms the two are equivalent. Whilst there are some stragglers left
      (dma_max_pfn(), I'm looking at you...), the majority of DMA code has
      been cleaned up to follow the latter definition, not least since it is
      the only one which makes sense once IOMMUs are involved.
      
      In this respect, of_dma_configure() has always done the wrong thing in
      how it generates initial masks based on "dma-ranges". Although rounding
      down did not affect the TI Keystone platform where dma_addr + size is
      already a power of two, in any other case it results in a mask which is
      at best unnecessarily constrained and at worst unusable.
      
      BCM2837 illustrates the problem nicely, where we have a DMA base of 3GB
      and a size of 1GB - 16MB, giving dma_addr + size = 0xff000000 and a
      resultant mask of 0x7fffffff, which is then insufficient to even cover
      the necessary offset, effectively making all DMA addresses out-of-range.
      This has been hidden until now (mostly because we don't yet prevent
      drivers from simply overwriting this initial mask later upon probe), but
      due to recent changes elsewhere now shows up as USB being broken on
      Raspberry Pi 3.
      
      Make it right by rounding up instead of down, such that the mask
      correctly correctly describes all possisble bits the device needs to
      emit.
      
      Fixes: 9a6d7298 ("of: Calculate device DMA masks based on DT dma-range size")
      Reported-by: default avatarStefan Wahren <stefan.wahren@i2se.com>
      Reported-by: default avatarAndreas Färber <afaerber@suse.de>
      Reported-by: default avatarHans Verkuil <hverkuil@xs4all.nl>
      Signed-off-by: default avatarRobin Murphy <robin.murphy@arm.com>
      Acked-by: default avatarRob Herring <robh@kernel.org>
      Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      ee7b1f31
    • Linus Torvalds's avatar
      Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi · ac9a4090
      Linus Torvalds authored
      Pull SCSI fixes from James Bottomley:
       "A couple of minor fixes (st, ses) and some bigger driver fixes for
        qla2xxx (crash triggered by fw dump) and ipr (lockdep problems with
        mq)"
      
      * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
        scsi: ses: Fix wrong page error
        scsi: ipr: Fix scsi-mq lockdep issue
        scsi: st: fix blk_get_queue usage
        scsi: qla2xxx: Fix system crash while triggering FW dump
      ac9a4090
  3. 16 Aug, 2017 4 commits