1. 03 Mar, 2016 37 commits
    • Sasha Levin's avatar
      RDS: verify the underlying transport exists before creating a connection · d596f66d
      Sasha Levin authored
      commit 74e98eb0 upstream.
      
      There was no verification that an underlying transport exists when creating
      a connection, this would cause dereferencing a NULL ptr.
      
      It might happen on sockets that weren't properly bound before attempting to
      send a message, which will cause a NULL ptr deref:
      
      [135546.047719] kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC KASAN
      [135546.051270] Modules linked in:
      [135546.051781] CPU: 4 PID: 15650 Comm: trinity-c4 Not tainted 4.2.0-next-20150902-sasha-00041-gbaa1222-dirty #2527
      [135546.053217] task: ffff8800835bc000 ti: ffff8800bc708000 task.ti: ffff8800bc708000
      [135546.054291] RIP: __rds_conn_create (net/rds/connection.c:194)
      [135546.055666] RSP: 0018:ffff8800bc70fab0  EFLAGS: 00010202
      [135546.056457] RAX: dffffc0000000000 RBX: 0000000000000f2c RCX: ffff8800835bc000
      [135546.057494] RDX: 0000000000000007 RSI: ffff8800835bccd8 RDI: 0000000000000038
      [135546.058530] RBP: ffff8800bc70fb18 R08: 0000000000000001 R09: 0000000000000000
      [135546.059556] R10: ffffed014d7a3a23 R11: ffffed014d7a3a21 R12: 0000000000000000
      [135546.060614] R13: 0000000000000001 R14: ffff8801ec3d0000 R15: 0000000000000000
      [135546.061668] FS:  00007faad4ffb700(0000) GS:ffff880252000000(0000) knlGS:0000000000000000
      [135546.062836] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
      [135546.063682] CR2: 000000000000846a CR3: 000000009d137000 CR4: 00000000000006a0
      [135546.064723] Stack:
      [135546.065048]  ffffffffafe2055c ffffffffafe23fc1 ffffed00493097bf ffff8801ec3d0008
      [135546.066247]  0000000000000000 00000000000000d0 0000000000000000 ac194a24c0586342
      [135546.067438]  1ffff100178e1f78 ffff880320581b00 ffff8800bc70fdd0 ffff880320581b00
      [135546.068629] Call Trace:
      [135546.069028] ? __rds_conn_create (include/linux/rcupdate.h:856 net/rds/connection.c:134)
      [135546.069989] ? rds_message_copy_from_user (net/rds/message.c:298)
      [135546.071021] rds_conn_create_outgoing (net/rds/connection.c:278)
      [135546.071981] rds_sendmsg (net/rds/send.c:1058)
      [135546.072858] ? perf_trace_lock (include/trace/events/lock.h:38)
      [135546.073744] ? lockdep_init (kernel/locking/lockdep.c:3298)
      [135546.074577] ? rds_send_drop_to (net/rds/send.c:976)
      [135546.075508] ? __might_fault (./arch/x86/include/asm/current.h:14 mm/memory.c:3795)
      [135546.076349] ? __might_fault (mm/memory.c:3795)
      [135546.077179] ? rds_send_drop_to (net/rds/send.c:976)
      [135546.078114] sock_sendmsg (net/socket.c:611 net/socket.c:620)
      [135546.078856] SYSC_sendto (net/socket.c:1657)
      [135546.079596] ? SYSC_connect (net/socket.c:1628)
      [135546.080510] ? trace_dump_stack (kernel/trace/trace.c:1926)
      [135546.081397] ? ring_buffer_unlock_commit (kernel/trace/ring_buffer.c:2479 kernel/trace/ring_buffer.c:2558 kernel/trace/ring_buffer.c:2674)
      [135546.082390] ? trace_buffer_unlock_commit (kernel/trace/trace.c:1749)
      [135546.083410] ? trace_event_raw_event_sys_enter (include/trace/events/syscalls.h:16)
      [135546.084481] ? do_audit_syscall_entry (include/trace/events/syscalls.h:16)
      [135546.085438] ? trace_buffer_unlock_commit (kernel/trace/trace.c:1749)
      [135546.085515] rds_ib_laddr_check(): addr 36.74.25.172 ret -99 node type -1
      Acked-by: default avatarSantosh Shilimkar <santosh.shilimkar@oracle.com>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Cc: "Charles (Chas) Williams" <3chas3@gmail.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      d596f66d
    • Marcelo Leitner's avatar
      ipv6: addrconf: validate new MTU before applying it · db449d87
      Marcelo Leitner authored
      commit 77751427 upstream.
      
      Currently we don't check if the new MTU is valid or not and this allows
      one to configure a smaller than minimum allowed by RFCs or even bigger
      than interface own MTU, which is a problem as it may lead to packet
      drops.
      
      If you have a daemon like NetworkManager running, this may be exploited
      by remote attackers by forging RA packets with an invalid MTU, possibly
      leading to a DoS. (NetworkManager currently only validates for values
      too small, but not for too big ones.)
      
      The fix is just to make sure the new value is valid. That is, between
      IPV6_MIN_MTU and interface's MTU.
      
      Note that similar check is already performed at
      ndisc_router_discovery(), for when kernel itself parses the RA.
      Signed-off-by: default avatarMarcelo Ricardo Leitner <mleitner@redhat.com>
      Signed-off-by: default avatarSabrina Dubroca <sd@queasysnail.net>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Cc: "Charles (Chas) Williams" <3chas3@gmail.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      db449d87
    • James Hogan's avatar
      MIPS: KVM: Uninit VCPU in vcpu_create error path · bf229d80
      James Hogan authored
      commit 585bb8f9 upstream.
      
      If either of the memory allocations in kvm_arch_vcpu_create() fail, the
      vcpu which has been allocated and kvm_vcpu_init'd doesn't get uninit'd
      in the error handling path. Add a call to kvm_vcpu_uninit() to fix this.
      
      Fixes: 669e846e ("KVM/MIPS32: MIPS arch specific APIs for KVM")
      Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Gleb Natapov <gleb@kernel.org>
      Cc: linux-mips@linux-mips.org
      Cc: kvm@vger.kernel.org
      Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
      Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      bf229d80
    • James Hogan's avatar
      MIPS: KVM: Fix CACHE immediate offset sign extension · f1a718fd
      James Hogan authored
      commit c5c2a3b9 upstream.
      
      The immediate field of the CACHE instruction is signed, so ensure that
      it gets sign extended by casting it to an int16_t rather than just
      masking the low 16 bits.
      
      Fixes: e685c689 ("KVM/MIPS32: Privileged instruction/target branch emulation.")
      Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Gleb Natapov <gleb@kernel.org>
      Cc: linux-mips@linux-mips.org
      Cc: kvm@vger.kernel.org
      Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
      Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      f1a718fd
    • James Hogan's avatar
      MIPS: KVM: Fix ASID restoration logic · 2fde5f91
      James Hogan authored
      commit 002374f3 upstream.
      
      ASID restoration on guest resume should determine the guest execution
      mode based on the guest Status register rather than bit 30 of the guest
      PC.
      
      Fix the two places in locore.S that do this, loading the guest status
      from the cop0 area. Note, this assembly is specific to the trap &
      emulate implementation of KVM, so it doesn't need to check the
      supervisor bit as that mode is not implemented in the guest.
      
      Fixes: b680f70f ("KVM/MIPS32: Entry point for trampolining to...")
      Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Gleb Natapov <gleb@kernel.org>
      Cc: linux-mips@linux-mips.org
      Cc: kvm@vger.kernel.org
      Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
      Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      2fde5f91
    • Al Viro's avatar
      lock_parent: don't step on stale ->d_parent of all-but-freed one · 4d57edcd
      Al Viro authored
      commit c2338f2d upstream.
      
      Dentry that had been through (or into) __dentry_kill() might be seen
      by shrink_dentry_list(); that's normal, it'll be taken off the shrink
      list and freed if __dentry_kill() has already finished.  The problem
      is, its ->d_parent might be pointing to already freed dentry, so
      lock_parent() needs to be careful.
      
      We need to check that dentry hasn't already gone into __dentry_kill()
      *and* grab rcu_read_lock() before dropping ->d_lock - the latter makes
      sure that whatever we see in ->d_parent after dropping ->d_lock it
      won't be freed until we drop rcu_read_lock().
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      4d57edcd
    • Linus Torvalds's avatar
      dcache: add missing lockdep annotation · 001869c3
      Linus Torvalds authored
      commit 9f12600f upstream.
      
      lock_parent() very much on purpose does nested locking of dentries, and
      is careful to maintain the right order (lock parent first).  But because
      it didn't annotate the nested locking order, lockdep thought it might be
      a deadlock on d_lock, and complained.
      
      Add the proper annotation for the inner locking of the child dentry to
      make lockdep happy.
      
      Introduced by commit 046b961b ("shrink_dentry_list(): take parent's
      ->d_lock earlier").
      Reported-and-tested-by: default avatarJosh Boyer <jwboyer@fedoraproject.org>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      001869c3
    • Al Viro's avatar
      dentry_kill() doesn't need the second argument now · b004c3a7
      Al Viro authored
      commit 8cbf74da upstream.
      
      it's 1 in the only remaining caller.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b004c3a7
    • Al Viro's avatar
      dealing with the rest of shrink_dentry_list() livelock · 6179fe37
      Al Viro authored
      commit b2b80195 upstream.
      
      We have the same problem with ->d_lock order in the inner loop, where
      we are dropping references to ancestors.  Same solution, basically -
      instead of using dentry_kill() we use lock_parent() (introduced in the
      previous commit) to get that lock in a safe way, recheck ->d_count
      (in case if lock_parent() has ended up dropping and retaking ->d_lock
      and somebody managed to grab a reference during that window), trylock
      the inode->i_lock and use __dentry_kill() to do the rest.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      6179fe37
    • Al Viro's avatar
      shrink_dentry_list(): take parent's ->d_lock earlier · 286adf77
      Al Viro authored
      commit 046b961b upstream.
      
      The cause of livelocks there is that we are taking ->d_lock on
      dentry and its parent in the wrong order, forcing us to use
      trylock on the parent's one.  d_walk() takes them in the right
      order, and unfortunately it's not hard to create a situation
      when shrink_dentry_list() can't make progress since trylock
      keeps failing, and shrink_dcache_parent() or check_submounts_and_drop()
      keeps calling d_walk() disrupting the very shrink_dentry_list() it's
      waiting for.
      
      Solution is straightforward - if that trylock fails, let's unlock
      the dentry itself and take locks in the right order.  We need to
      stabilize ->d_parent without holding ->d_lock, but that's doable
      using RCU.  And we'd better do that in the very beginning of the
      loop in shrink_dentry_list(), since the checks on refcount, etc.
      would need to be redone anyway.
      
      That deals with a half of the problem - killing dentries on the
      shrink list itself.  Another one (dropping their parents) is
      in the next commit.
      
      locking parent is interesting - it would be easy to do rcu_read_lock(),
      lock whatever we think is a parent, lock dentry itself and check
      if the parent is still the right one.  Except that we need to check
      that *before* locking the dentry, or we are risking taking ->d_lock
      out of order.  Fortunately, once the D1 is locked, we can check if
      D2->d_parent is equal to D1 without the need to lock D2; D2->d_parent
      can start or stop pointing to D1 only under D1->d_lock, so taking
      D1->d_lock is enough.  In other words, the right solution is
      rcu_read_lock/lock what looks like parent right now/check if it's
      still our parent/rcu_read_unlock/lock the child.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      286adf77
    • Al Viro's avatar
      expand dentry_kill(dentry, 0) in shrink_dentry_list() · d2cac5b6
      Al Viro authored
      commit ff2fde99 upstream.
      
      Result will be massaged to saner shape in the next commits.  It is
      ugly, no questions - the point of that one is to be a provably
      equivalent transformation (and it might be worth splitting a bit
      more).
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      d2cac5b6
    • Al Viro's avatar
      split dentry_kill() · c233eac2
      Al Viro authored
      commit e55fd011 upstream.
      
      ... into trylocks and everything else.  The latter (actual killing)
      is __dentry_kill().
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      c233eac2
    • Al Viro's avatar
      lift the "already marked killed" case into shrink_dentry_list() · f718ea38
      Al Viro authored
      commit 64fd72e0 upstream.
      
      It can happen only when dentry_kill() is called with unlock_on_failure
      equal to 0 - other callers had dentry pinned until the moment they've
      got ->d_lock and DCACHE_DENTRY_KILLED is set only after lockref_mark_dead().
      
      IOW, only one of three call sites of dentry_kill() might end up reaching
      that code.  Just move it there.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      f718ea38
    • Hariprasad S's avatar
      iw_cxgb3: Fix incorrectly returning error on success · 8e0cb6c1
      Hariprasad S authored
      commit 67f1aee6 upstream.
      
      The cxgb3_*_send() functions return NET_XMIT_ values, which are
      positive integers values. So don't treat positive return values
      as an error.
      Signed-off-by: default avatarSteve Wise <swise@opengridcomputing.com>
      Signed-off-by: default avatarHariprasad Shenai <hariprasad@chelsio.com>
      Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
      [a pox on developers and maintainers who do not cc: stable for bug fixes like this - gregkh]
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      8e0cb6c1
    • Corey Wright's avatar
      proc: Fix ptrace-based permission checks for accessing task maps · 223c6766
      Corey Wright authored
      Modify mm_access() calls in fs/proc/task_mmu.c and fs/proc/task_nommu.c to
      have the mode include PTRACE_MODE_FSCREDS so accessing /proc/pid/maps and
      /proc/pid/pagemap is not denied to all users.
      
      In backporting upstream commit caaee623 to pre-3.18 kernel versions it was
      overlooked that mm_access() is used in fs/proc/task_*mmu.c as those calls
      were removed in 3.18 (by upstream commit 29a40ace) and did not exist at the
      time of the original commit.
      Signed-off-by: default avatarCorey Wright <undefined@pobox.com>
      Acked-by: default avatarJann Horn <jann@thejh.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      223c6766
    • Bjørn Mork's avatar
      USB: option: add "4G LTE usb-modem U901" · 235679d9
      Bjørn Mork authored
      commit d061c1ca upstream.
      
      Thomas reports:
      
      T:  Bus=01 Lev=01 Prnt=01 Port=03 Cnt=01 Dev#=  4 Spd=480 MxCh= 0
      D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
      P:  Vendor=05c6 ProdID=6001 Rev=00.00
      S:  Manufacturer=USB Modem
      S:  Product=USB Modem
      S:  SerialNumber=1234567890ABCDEF
      C:  #Ifs= 5 Cfg#= 1 Atr=e0 MxPwr=500mA
      I:  If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
      I:  If#= 1 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
      I:  If#= 2 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
      I:  If#= 3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=qmi_wwan
      I:  If#= 4 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=usb-storage
      Reported-by: default avatarThomas Schäfer <tschaefer@t-online.de>
      Signed-off-by: default avatarBjørn Mork <bjorn@mork.no>
      Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      235679d9
    • Andrey Skvortsov's avatar
      USB: option: add support for SIM7100E · 287522d7
      Andrey Skvortsov authored
      commit 3158a8d4 upstream.
      
      $ lsusb:
      Bus 001 Device 101: ID 1e0e:9001 Qualcomm / Option
      
      $ usb-devices:
      T:  Bus=01 Lev=02 Prnt=02 Port=00 Cnt=01 Dev#=101 Spd=480  MxCh= 0
      D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  2
      P:  Vendor=1e0e ProdID=9001 Rev= 2.32
      S:  Manufacturer=SimTech, Incorporated
      S:  Product=SimTech, Incorporated
      S:  SerialNumber=0123456789ABCDEF
      C:* #Ifs= 7 Cfg#= 1 Atr=80 MxPwr=500mA
      I:* If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
      I:* If#= 1 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option
      I:* If#= 2 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option
      I:* If#= 3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option
      I:* If#= 4 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option
      I:* If#= 5 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=qmi_wwan
      I:* If#= 6 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=42 Prot=01 Driver=(none)
      
      The last interface (6) is used for Android Composite ADB interface.
      
      Serial port layout:
      0: QCDM/DIAG
      1: NMEA
      2: AT
      3: AT/PPP
      4: audio
      Signed-off-by: default avatarAndrey Skvortsov <andrej.skvortzov@gmail.com>
      Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      287522d7
    • Ken Lin's avatar
      USB: cp210x: add IDs for GE B650V3 and B850V3 boards · 315c1d00
      Ken Lin authored
      commit 6627ae19 upstream.
      
      Add USB ID for cp2104/5 devices on GE B650v3 and B850v3 boards.
      Signed-off-by: default avatarKen Lin <ken.lin@advantech.com.tw>
      Signed-off-by: default avatarAkshay Bhat <akshay.bhat@timesys.com>
      Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      315c1d00
    • Gerhard Uttenthaler's avatar
      can: ems_usb: Fix possible tx overflow · 02673048
      Gerhard Uttenthaler authored
      commit 90cfde46 upstream.
      
      This patch fixes the problem that more CAN messages could be sent to the
      interface as could be send on the CAN bus. This was more likely for slow baud
      rates. The sleeping _start_xmit was woken up in the _write_bulk_callback. Under
      heavy TX load this produced another bulk transfer without checking the
      free_slots variable and hence caused the overflow in the interface.
      Signed-off-by: default avatarGerhard Uttenthaler <uttenthaler@ems-wuensche.com>
      Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      02673048
    • Nikolay Borisov's avatar
      dm thin: fix race condition when destroying thin pool workqueue · 5e297a6a
      Nikolay Borisov authored
      commit 18d03e8c upstream.
      
      When a thin pool is being destroyed delayed work items are
      cancelled using cancel_delayed_work(), which doesn't guarantee that on
      return the delayed item isn't running.  This can cause the work item to
      requeue itself on an already destroyed workqueue.  Fix this by using
      cancel_delayed_work_sync() which guarantees that on return the work item
      is not running anymore.
      
      Fixes: 905e51b3 ("dm thin: commit outstanding data every second")
      Fixes: 85ad643b ("dm thin: add timeout to stop out-of-data-space mode holding IO forever")
      Signed-off-by: default avatarNikolay Borisov <kernel@kyup.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      5e297a6a
    • Joe Thornber's avatar
      dm thin metadata: fix bug when taking a metadata snapshot · eb44c5a6
      Joe Thornber authored
      commit 49e99fc7 upstream.
      
      When you take a metadata snapshot the btree roots for the mapping and
      details tree need to have their reference counts incremented so they
      persist for the lifetime of the metadata snap.
      
      The roots being incremented were those currently written in the
      superblock, which could possibly be out of date if concurrent IO is
      triggering new mappings, breaking of sharing, etc.
      
      Fix this by performing a commit with the metadata lock held while taking
      a metadata snapshot.
      Signed-off-by: default avatarJoe Thornber <ejt@redhat.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      eb44c5a6
    • Mike Snitzer's avatar
      dm thin: restore requested 'error_if_no_space' setting on OODS to WRITE transition · 613c515d
      Mike Snitzer authored
      commit 172c2386 upstream.
      
      A thin-pool that is in out-of-data-space (OODS) mode may transition back
      to write mode -- without the admin adding more space to the thin-pool --
      if/when blocks are released (either by deleting thin devices or
      discarding provisioned blocks).
      
      But as part of the thin-pool's earlier transition to out-of-data-space
      mode the thin-pool may have set the 'error_if_no_space' flag to true if
      the no_space_timeout expires without more space having been made
      available.  That implementation detail, of changing the pool's
      error_if_no_space setting, needs to be reset back to the default that
      the user specified when the thin-pool's table was loaded.
      
      Otherwise we'll drop the user requested behaviour on the floor when this
      out-of-data-space to write mode transition occurs.
      Reported-by: default avatarVivek Goyal <vgoyal@redhat.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Acked-by: default avatarJoe Thornber <ejt@redhat.com>
      Fixes: 2c43fd26 ("dm thin: fix missing out-of-data-space to write mode transition if blocks are released")
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      613c515d
    • Ingo Molnar's avatar
      efi: Disable interrupts around EFI calls, not in the epilog/prolog calls · 9dd9ef83
      Ingo Molnar authored
      commit 23a0d4e8 upstream.
      
      Tapasweni Pathak reported that we do a kmalloc() in efi_call_phys_prolog()
      on x86-64 while having interrupts disabled, which is a big no-no, as
      kmalloc() can sleep.
      
      Solve this by removing the irq disabling from the prolog/epilog calls
      around EFI calls: it's unnecessary, as in this stage we are single
      threaded in the boot thread, and we don't ever execute this from
      interrupt contexts.
      Reported-by: default avatarTapasweni Pathak <tapaswenipathak@gmail.com>
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      Signed-off-by: default avatarMatt Fleming <matt.fleming@intel.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      9dd9ef83
    • Dave Airlie's avatar
      drm/radeon: fix hotplug race at startup · e133febe
      Dave Airlie authored
      commit 7f98ca45 upstream.
      
      We apparantly get a hotplug irq before we've initialised
      modesetting,
      
      [drm] Loading R100 Microcode
      BUG: unable to handle kernel NULL pointer dereference at   (null)
      IP: [<c125f56f>] __mutex_lock_slowpath+0x23/0x91
      *pde = 00000000
      Oops: 0002 [#1]
      Modules linked in: radeon(+) drm_kms_helper ttm drm i2c_algo_bit backlight pcspkr psmouse evdev sr_mod input_leds led_class cdrom sg parport_pc parport floppy intel_agp intel_gtt lpc_ich acpi_cpufreq processor button mfd_core agpgart uhci_hcd ehci_hcd rng_core snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm usbcore usb_common i2c_i801 i2c_core snd_timer snd soundcore thermal_sys
      CPU: 0 PID: 15 Comm: kworker/0:1 Not tainted 4.2.0-rc7-00015-gbf674028 #111
      Hardware name: MicroLink                               /D850MV                         , BIOS MV85010A.86A.0067.P24.0304081124 04/08/2003
      Workqueue: events radeon_hotplug_work_func [radeon]
      task: f6ca5900 ti: f6d3e000 task.ti: f6d3e000
      EIP: 0060:[<c125f56f>] EFLAGS: 00010282 CPU: 0
      EIP is at __mutex_lock_slowpath+0x23/0x91
      EAX: 00000000 EBX: f5e900fc ECX: 00000000 EDX: fffffffe
      ESI: f6ca5900 EDI: f5e90100 EBP: f5e90000 ESP: f6d3ff0c
       DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068
      CR0: 8005003b CR2: 00000000 CR3: 36f61000 CR4: 000006d0
      Stack:
       f5e90100 00000000 c103c4c1 f6d2a5a0 f5e900fc f6df394c c125f162 f8b0faca
       f6d2a5a0 c138ca00 f6df394c f7395600 c1034741 00d40000 00000000 f6d2a5a0
       c138ca00 f6d2a5b8 c138ca10 c1034b58 00000001 f6d40000 f6ca5900 f6d0c940
      Call Trace:
       [<c103c4c1>] ? dequeue_task_fair+0xa4/0xb7
       [<c125f162>] ? mutex_lock+0x9/0xa
       [<f8b0faca>] ? radeon_hotplug_work_func+0x17/0x57 [radeon]
       [<c1034741>] ? process_one_work+0xfc/0x194
       [<c1034b58>] ? worker_thread+0x18d/0x218
       [<c10349cb>] ? rescuer_thread+0x1d5/0x1d5
       [<c103742a>] ? kthread+0x7b/0x80
       [<c12601c0>] ? ret_from_kernel_thread+0x20/0x30
       [<c10373af>] ? init_completion+0x18/0x18
      Code: 42 08 e8 8e a6 dd ff c3 57 56 53 83 ec 0c 8b 35 48 f7 37 c1 8b 10 4a 74 1a 89 c3 8d 78 04 8b 40 08 89 63
      Reported-and-Tested-by: default avatarMeelis Roos <mroos@linux.ee>
      Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      e133febe
    • Kamal Mostafa's avatar
      tools: Add a "make all" rule · 12ce3017
      Kamal Mostafa authored
      commit f6ba98c5 upstream.
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      Acked-by: default avatarPavel Machek <pavel@ucw.cz>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Jonathan Cameron <jic23@kernel.org>
      Cc: Pali Rohar <pali.rohar@gmail.com>
      Cc: Roberta Dobrescu <roberta.dobrescu@gmail.com>
      Link: http://lkml.kernel.org/r/1447280736-2161-2-git-send-email-kamal@canonical.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      [ kamal: backport to 3.14-stable: build all tools for this version ]
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      12ce3017
    • Kent Overstreet's avatar
      bcache: Change refill_dirty() to always scan entire disk if necessary · e5a1ede9
      Kent Overstreet authored
      commit 627ccd20 upstream.
      
      Previously, it would only scan the entire disk if it was starting from
      the very start of the disk - i.e. if the previous scan got to the end.
      
      This was broken by refill_full_stripes(), which updates last_scanned so
      that refill_dirty was never triggering the searched_from_start path.
      
      But if we change refill_dirty() to always scan the entire disk if
      necessary, regardless of what last_scanned was, the code gets cleaner
      and we fix that bug too.
      Signed-off-by: default avatarKent Overstreet <kent.overstreet@gmail.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      e5a1ede9
    • Stefan Bader's avatar
      bcache: prevent crash on changing writeback_running · cf53efaa
      Stefan Bader authored
      commit 8d16ce54 upstream.
      
      Added a safeguard in the shutdown case. At least while not being
      attached it is also possible to trigger a kernel bug by writing into
      writeback_running. This change  adds the same check before trying to
      wake up the thread for that case.
      Signed-off-by: default avatarStefan Bader <stefan.bader@canonical.com>
      Cc: Kent Overstreet <kent.overstreet@gmail.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      cf53efaa
    • Zheng Liu's avatar
      bcache: unregister reboot notifier if bcache fails to unregister device · 283ab757
      Zheng Liu authored
      commit 2ecf0cdb upstream.
      
      In bcache_init() function it forgot to unregister reboot notifier if
      bcache fails to unregister a block device.  This commit fixes this.
      Signed-off-by: default avatarZheng Liu <wenqing.lz@taobao.com>
      Tested-by: default avatarJoshua Schmid <jschmid@suse.com>
      Tested-by: default avatarEric Wheeler <bcache@linux.ewheeler.net>
      Cc: Kent Overstreet <kmo@daterainc.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      283ab757
    • Al Viro's avatar
      bcache: fix a leak in bch_cached_dev_run() · dba6700e
      Al Viro authored
      commit 4d4d8573 upstream.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Tested-by: default avatarJoshua Schmid <jschmid@suse.com>
      Tested-by: default avatarEric Wheeler <bcache@linux.ewheeler.net>
      Cc: Kent Overstreet <kmo@daterainc.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      dba6700e
    • Zheng Liu's avatar
      bcache: clear BCACHE_DEV_UNLINK_DONE flag when attaching a backing device · ffed442c
      Zheng Liu authored
      commit fecaee6f upstream.
      
      This bug can be reproduced by the following script:
      
        #!/bin/bash
      
        bcache_sysfs="/sys/fs/bcache"
      
        function clear_cache()
        {
        	if [ ! -e $bcache_sysfs ]; then
        		echo "no bcache sysfs"
        		exit
        	fi
      
        	cset_uuid=$(ls -l $bcache_sysfs|head -n 2|tail -n 1|awk '{print $9}')
        	sudo sh -c "echo $cset_uuid > /sys/block/sdb/sdb1/bcache/detach"
        	sleep 5
        	sudo sh -c "echo $cset_uuid > /sys/block/sdb/sdb1/bcache/attach"
        }
      
        for ((i=0;i<10;i++)); do
        	clear_cache
        done
      
      The warning messages look like below:
      [  275.948611] ------------[ cut here ]------------
      [  275.963840] WARNING: at fs/sysfs/dir.c:512 sysfs_add_one+0xb8/0xd0() (Tainted: P        W
      ---------------   )
      [  275.979253] Hardware name: Tecal RH2285
      [  275.994106] sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:09.0/0000:08:00.0/host4/target4:2:1/4:2:1:0/block/sdb/sdb1/bcache/cache'
      [  276.024105] Modules linked in: bcache tcp_diag inet_diag ipmi_devintf ipmi_si ipmi_msghandler
      bonding 8021q garp stp llc ipv6 ext3 jbd loop sg iomemory_vsl(P) bnx2 microcode serio_raw i2c_i801
      i2c_core iTCO_wdt iTCO_vendor_support i7core_edac edac_core shpchp ext4 jbd2 mbcache megaraid_sas
      pata_acpi ata_generic ata_piix dm_mod [last unloaded: scsi_wait_scan]
      [  276.072643] Pid: 2765, comm: sh Tainted: P        W  ---------------    2.6.32 #1
      [  276.089315] Call Trace:
      [  276.105801]  [<ffffffff81070fe7>] ? warn_slowpath_common+0x87/0xc0
      [  276.122650]  [<ffffffff810710d6>] ? warn_slowpath_fmt+0x46/0x50
      [  276.139361]  [<ffffffff81205c08>] ? sysfs_add_one+0xb8/0xd0
      [  276.156012]  [<ffffffff8120609b>] ? sysfs_do_create_link+0x12b/0x170
      [  276.172682]  [<ffffffff81206113>] ? sysfs_create_link+0x13/0x20
      [  276.189282]  [<ffffffffa03bda21>] ? bcache_device_link+0xc1/0x110 [bcache]
      [  276.205993]  [<ffffffffa03bfa08>] ? bch_cached_dev_attach+0x478/0x4f0 [bcache]
      [  276.222794]  [<ffffffffa03c4a17>] ? bch_cached_dev_store+0x627/0x780 [bcache]
      [  276.239680]  [<ffffffff8116783a>] ? alloc_pages_current+0xaa/0x110
      [  276.256594]  [<ffffffff81203b15>] ? sysfs_write_file+0xe5/0x170
      [  276.273364]  [<ffffffff811887b8>] ? vfs_write+0xb8/0x1a0
      [  276.290133]  [<ffffffff811890b1>] ? sys_write+0x51/0x90
      [  276.306368]  [<ffffffff8100c072>] ? system_call_fastpath+0x16/0x1b
      [  276.322301] ---[ end trace 9f5d4fcdd0c3edfb ]---
      [  276.338241] ------------[ cut here ]------------
      [  276.354109] WARNING: at /home/wenqing.lz/bcache/bcache/super.c:720
      bcache_device_link+0xdf/0x110 [bcache]() (Tainted: P        W  ---------------   )
      [  276.386017] Hardware name: Tecal RH2285
      [  276.401430] Couldn't create device <-> cache set symlinks
      [  276.401759] Modules linked in: bcache tcp_diag inet_diag ipmi_devintf ipmi_si ipmi_msghandler
      bonding 8021q garp stp llc ipv6 ext3 jbd loop sg iomemory_vsl(P) bnx2 microcode serio_raw i2c_i801
      i2c_core iTCO_wdt iTCO_vendor_support i7core_edac edac_core shpchp ext4 jbd2 mbcache megaraid_sas
      pata_acpi ata_generic ata_piix dm_mod [last unloaded: scsi_wait_scan]
      [  276.465477] Pid: 2765, comm: sh Tainted: P        W  ---------------    2.6.32 #1
      [  276.482169] Call Trace:
      [  276.498610]  [<ffffffff81070fe7>] ? warn_slowpath_common+0x87/0xc0
      [  276.515405]  [<ffffffff810710d6>] ? warn_slowpath_fmt+0x46/0x50
      [  276.532059]  [<ffffffffa03bda3f>] ? bcache_device_link+0xdf/0x110 [bcache]
      [  276.548808]  [<ffffffffa03bfa08>] ? bch_cached_dev_attach+0x478/0x4f0 [bcache]
      [  276.565569]  [<ffffffffa03c4a17>] ? bch_cached_dev_store+0x627/0x780 [bcache]
      [  276.582418]  [<ffffffff8116783a>] ? alloc_pages_current+0xaa/0x110
      [  276.599341]  [<ffffffff81203b15>] ? sysfs_write_file+0xe5/0x170
      [  276.616142]  [<ffffffff811887b8>] ? vfs_write+0xb8/0x1a0
      [  276.632607]  [<ffffffff811890b1>] ? sys_write+0x51/0x90
      [  276.648671]  [<ffffffff8100c072>] ? system_call_fastpath+0x16/0x1b
      [  276.664756] ---[ end trace 9f5d4fcdd0c3edfc ]---
      
      We forget to clear BCACHE_DEV_UNLINK_DONE flag in bcache_device_attach()
      function when we attach a backing device first time.  After detaching this
      backing device, this flag will be true and sysfs_remove_link() isn't called in
      bcache_device_unlink().  Then when we attach this backing device again,
      sysfs_create_link() will return EEXIST error in bcache_device_link().
      
      So the fix is trival and we clear this flag in bcache_device_link().
      Signed-off-by: default avatarZheng Liu <wenqing.lz@taobao.com>
      Tested-by: default avatarJoshua Schmid <jschmid@suse.com>
      Tested-by: default avatarEric Wheeler <bcache@linux.ewheeler.net>
      Cc: Kent Overstreet <kmo@daterainc.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      ffed442c
    • Kent Overstreet's avatar
      bcache: Add a cond_resched() call to gc · b7ce521d
      Kent Overstreet authored
      commit c5f1e5ad upstream.
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Tested-by: default avatarEric Wheeler <bcache@linux.ewheeler.net>
      Cc: Kent Overstreet <kmo@daterainc.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b7ce521d
    • Zheng Liu's avatar
      bcache: fix a livelock when we cause a huge number of cache misses · 1d348932
      Zheng Liu authored
      commit 2ef9ccbf upstream.
      
      Subject :	[PATCH v2] bcache: fix a livelock in btree lock
      Date :	Wed, 25 Feb 2015 20:32:09 +0800 (02/25/2015 04:32:09 AM)
      
      This commit tries to fix a livelock in bcache.  This livelock might
      happen when we causes a huge number of cache misses simultaneously.
      
      When we get a cache miss, bcache will execute the following path.
      
      ->cached_dev_make_request()
        ->cached_dev_read()
          ->cached_lookup()
            ->bch->btree_map_keys()
              ->btree_root()  <------------------------
                ->bch_btree_map_keys_recurse()        |
                  ->cache_lookup_fn()                 |
                    ->cached_dev_cache_miss()         |
                      ->bch_btree_insert_check_key() -|
                        [If btree->seq is not equal to seq + 1, we should return
                         EINTR and traverse btree again.]
      
      In bch_btree_insert_check_key() function we first need to check upgrade
      flag (op->lock == -1), and when this flag is true we need to release
      read btree->lock and try to take write btree->lock.  During taking and
      releasing this write lock, btree->seq will be monotone increased in
      order to prevent other threads modify this in cache miss (see btree.h:74).
      But if there are some cache misses caused by some requested, we could
      meet a livelock because btree->seq is always changed by others.  Thus no
      one can make progress.
      
      This commit will try to take write btree->lock if it encounters a race
      when we traverse btree.  Although it sacrifice the scalability but we
      can ensure that only one can modify the btree.
      Signed-off-by: default avatarZheng Liu <wenqing.lz@taobao.com>
      Tested-by: default avatarJoshua Schmid <jschmid@suse.com>
      Tested-by: default avatarEric Wheeler <bcache@linux.ewheeler.net>
      Cc: Joshua Schmid <jschmid@suse.com>
      Cc: Zhu Yanhai <zhu.yanhai@gmail.com>
      Cc: Kent Overstreet <kmo@daterainc.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      1d348932
    • Phil Sutter's avatar
      netfilter: ip6t_SYNPROXY: fix NULL pointer dereference · d70966f1
      Phil Sutter authored
      commit 96fffb4f upstream.
      
      This happens when networking namespaces are enabled.
      Suggested-by: default avatarPatrick McHardy <kaber@trash.net>
      Signed-off-by: default avatarPhil Sutter <phil@nwl.cc>
      Acked-by: default avatarPatrick McHardy <kaber@trash.net>
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      d70966f1
    • lucien's avatar
      netfilter: ipt_rpfilter: remove the nh_scope test in rpfilter_lookup_reverse · 905edc07
      lucien authored
      commit cc4998fe upstream.
      
      --accept-local  option works for res.type == RTN_LOCAL, which should be
      from the local table, but there, the fib_info's nh->nh_scope =
      RT_SCOPE_NOWHERE ( > RT_SCOPE_HOST). in fib_create_info().
      
      	if (cfg->fc_scope == RT_SCOPE_HOST) {
      		struct fib_nh *nh = fi->fib_nh;
      
      		/* Local address is added. */
      		if (nhs != 1 || nh->nh_gw)
      			goto err_inval;
      		nh->nh_scope = RT_SCOPE_NOWHERE;   <===
      		nh->nh_dev = dev_get_by_index(net, fi->fib_nh->nh_oif);
      		err = -ENODEV;
      		if (!nh->nh_dev)
      			goto failure;
      
      but in our rpfilter_lookup_reverse():
      
      	if (dev_match || flags & XT_RPFILTER_LOOSE)
      		return FIB_RES_NH(res).nh_scope <= RT_SCOPE_HOST;
      
      if nh->nh_scope > RT_SCOPE_HOST, it will fail. --accept-local option
      will never be passed.
      
      it seems the test is bogus and can be removed to fix this issue.
      
      	if (dev_match || flags & XT_RPFILTER_LOOSE)
      		return FIB_RES_NH(res).nh_scope <= RT_SCOPE_HOST;
      
      ipv6 does not have this issue.
      Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
      Acked-by: default avatarFlorian Westphal <fw@strlen.de>
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      905edc07
    • Mirek Kratochvil's avatar
      netfilter: nf_tables: fix bogus warning in nft_data_uninit() · 7447ae21
      Mirek Kratochvil authored
      commit 960bd2c2 upstream.
      
      The values 0x00000000-0xfffffeff are reserved for userspace datatype. When,
      deleting set elements with maps, a bogus warning is triggered.
      
      WARNING: CPU: 0 PID: 11133 at net/netfilter/nf_tables_api.c:4481 nft_data_uninit+0x35/0x40 [nf_tables]()
      
      This fixes the check accordingly to enum definition in
      include/linux/netfilter/nf_tables.h
      
      Fixes: https://bugzilla.netfilter.org/show_bug.cgi?id=1013Signed-off-by: default avatarMirek Kratochvil <exa.exa@gmail.com>
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      7447ae21
    • Egbert Eich's avatar
      drm/ast: Initialized data needed to map fbdev memory · 36913890
      Egbert Eich authored
      commit 28fb4cb7 upstream.
      
      Due to a missing initialization there was no way to map fbdev memory.
      Thus for example using the Xserver with the fbdev driver failed.
      This fix adds initialization for fix.smem_start and fix.smem_len
      in the fb_info structure, which fixes this problem.
      Requested-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
      Signed-off-by: default avatarEgbert Eich <eich@suse.de>
      [pulled from SuSE tree by me - airlied]
      Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      36913890
    • Steven Rostedt (Red Hat)'s avatar
      tracepoints: Do not trace when cpu is offline · af0fc20f
      Steven Rostedt (Red Hat) authored
      commit f3775549 upstream.
      
      The tracepoint infrastructure uses RCU sched protection to enable and
      disable tracepoints safely. There are some instances where tracepoints are
      used in infrastructure code (like kfree()) that get called after a CPU is
      going offline, and perhaps when it is coming back online but hasn't been
      registered yet.
      
      This can probuce the following warning:
      
       [ INFO: suspicious RCU usage. ]
       4.4.0-00006-g0fe53e8-dirty #34 Tainted: G S
       -------------------------------
       include/trace/events/kmem.h:141 suspicious rcu_dereference_check() usage!
      
       other info that might help us debug this:
      
       RCU used illegally from offline CPU!  rcu_scheduler_active = 1, debug_locks = 1
       no locks held by swapper/8/0.
      
       stack backtrace:
        CPU: 8 PID: 0 Comm: swapper/8 Tainted: G S              4.4.0-00006-g0fe53e8-dirty #34
        Call Trace:
        [c0000005b76c78d0] [c0000000008b9540] .dump_stack+0x98/0xd4 (unreliable)
        [c0000005b76c7950] [c00000000010c898] .lockdep_rcu_suspicious+0x108/0x170
        [c0000005b76c79e0] [c00000000029adc0] .kfree+0x390/0x440
        [c0000005b76c7a80] [c000000000055f74] .destroy_context+0x44/0x100
        [c0000005b76c7b00] [c0000000000934a0] .__mmdrop+0x60/0x150
        [c0000005b76c7b90] [c0000000000e3ff0] .idle_task_exit+0x130/0x140
        [c0000005b76c7c20] [c000000000075804] .pseries_mach_cpu_die+0x64/0x310
        [c0000005b76c7cd0] [c000000000043e7c] .cpu_die+0x3c/0x60
        [c0000005b76c7d40] [c0000000000188d8] .arch_cpu_idle_dead+0x28/0x40
        [c0000005b76c7db0] [c000000000101e6c] .cpu_startup_entry+0x50c/0x560
        [c0000005b76c7ed0] [c000000000043bd8] .start_secondary+0x328/0x360
        [c0000005b76c7f90] [c000000000008a6c] start_secondary_prolog+0x10/0x14
      
      This warning is not a false positive either. RCU is not protecting code that
      is being executed while the CPU is offline.
      
      Instead of playing "whack-a-mole(TM)" and adding conditional statements to
      the tracepoints we find that are used in this instance, simply add a
      cpu_online() test to the tracepoint code where the tracepoint will be
      ignored if the CPU is offline.
      
      Use of raw_smp_processor_id() is fine, as there should never be a case where
      the tracepoint code goes from running on a CPU that is online and suddenly
      gets migrated to a CPU that is offline.
      
      Link: http://lkml.kernel.org/r/1455387773-4245-1-git-send-email-kda@linux-powerpc.orgReported-by: default avatarDenis Kirjanov <kda@linux-powerpc.org>
      Fixes: 97e1c18e ("tracing: Kernel Tracepoints")
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      af0fc20f
  2. 25 Feb, 2016 3 commits