1. 31 Jan, 2019 23 commits
    • Rasmus Villemoes's avatar
      compiler.h: enable builtin overflow checkers and add fallback code · 1777fa96
      Rasmus Villemoes authored
      commit f0907827 upstream.
      
      This adds wrappers for the __builtin overflow checkers present in gcc
      5.1+ as well as fallback implementations for earlier compilers. It's not
      that easy to implement the fully generic __builtin_X_overflow(T1 a, T2
      b, T3 *d) in macros, so the fallback code assumes that T1, T2 and T3 are
      the same. We obviously don't want the wrappers to have different
      semantics depending on $GCC_VERSION, so we also insist on that even when
      using the builtins.
      
      There are a few problems with the 'a+b < a' idiom for checking for
      overflow: For signed types, it relies on undefined behaviour and is
      not actually complete (it doesn't check underflow;
      e.g. INT_MIN+INT_MIN == 0 isn't caught). Due to type promotion it
      is wrong for all types (signed and unsigned) narrower than
      int. Similarly, when a and b does not have the same type, there are
      subtle cases like
      
        u32 a;
      
        if (a + sizeof(foo) < a)
          return -EOVERFLOW;
        a += sizeof(foo);
      
      where the test is always false on 64 bit platforms. Add to that that it
      is not always possible to determine the types involved at a glance.
      
      The new overflow.h is somewhat bulky, but that's mostly a result of
      trying to be type-generic, complete (e.g. catching not only overflow
      but also signed underflow) and not relying on undefined behaviour.
      
      Linus is of course right [1] that for unsigned subtraction a-b, the
      right way to check for overflow (underflow) is "b > a" and not
      "__builtin_sub_overflow(a, b, &d)", but that's just one out of six cases
      covered here, and included mostly for completeness.
      
      So is it worth it? I think it is, if nothing else for the documentation
      value of seeing
      
        if (check_add_overflow(a, b, &d))
          return -EGOAWAY;
        do_stuff_with(d);
      
      instead of the open-coded (and possibly wrong and/or incomplete and/or
      UBsan-tickling)
      
        if (a+b < a)
          return -EGOAWAY;
        do_stuff_with(a+b);
      
      While gcc does recognize the 'a+b < a' idiom for testing unsigned add
      overflow, it doesn't do nearly as good for unsigned multiplication
      (there's also no single well-established idiom). So using
      check_mul_overflow in kcalloc and friends may also make gcc generate
      slightly better code.
      
      [1] https://lkml.org/lkml/2015/11/2/658Signed-off-by: default avatarRasmus Villemoes <linux@rasmusvillemoes.dk>
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      1777fa96
    • Tom Panfil's avatar
      Input: xpad - add support for SteelSeries Stratus Duo · c4a8adc4
      Tom Panfil authored
      commit fe2bfd0d upstream.
      
      Add support for the SteelSeries Stratus Duo, a wireless Xbox 360
      controller. The Stratus Duo ships with a USB dongle to enable wireless
      connectivity, but it can also function as a wired controller by connecting
      it directly to a PC via USB, hence the need for two USD PIDs. 0x1430 is the
      dongle, and 0x1431 is the controller.
      Signed-off-by: default avatarTom Panfil <tom@steelseries.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarDmitry Torokhov <dmitry.torokhov@gmail.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      c4a8adc4
    • Pavel Shilovsky's avatar
      CIFS: Fix possible hang during async MTU reads and writes · eb2fe47c
      Pavel Shilovsky authored
      commit acc58d0b upstream.
      
      When doing MTU i/o we need to leave some credits for
      possible reopen requests and other operations happening
      in parallel. Currently we leave 1 credit which is not
      enough even for reopen only: we need at least 2 credits
      if durable handle reconnect fails. Also there may be
      other operations at the same time including compounding
      ones which require 3 credits at a time each. Fix this
      by leaving 8 credits which is big enough to cover most
      scenarios.
      
      Was able to reproduce this when server was configured
      to give out fewer credits than usual.
      
      The proper fix would be to reconnect a file handle first
      and then obtain credits for an MTU request but this leads
      to bigger code changes and should happen in other patches.
      
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarPavel Shilovsky <pshilov@microsoft.com>
      Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      eb2fe47c
    • Paul Fulghum's avatar
      tty/n_hdlc: fix __might_sleep warning · 493f7583
      Paul Fulghum authored
      commit fc01d8c6 upstream.
      
      Fix __might_sleep warning[1] in tty/n_hdlc.c read due to copy_to_user
      call while current is TASK_INTERRUPTIBLE.  This is a false positive
      since the code path does not depend on current state remaining
      TASK_INTERRUPTIBLE.  The loop breaks out and sets TASK_RUNNING after
      calling copy_to_user.
      
      This patch supresses the warning by setting TASK_RUNNING before calling
      copy_to_user.
      
      [1] https://syzkaller.appspot.com/bug?id=17d5de7f1fcab794cb8c40032f893f52de899324Signed-off-by: default avatarPaul Fulghum <paulkf@microgate.com>
      Reported-by: default avatarsyzbot <syzbot+c244af085a0159d22879@syzkaller.appspotmail.com>
      Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
      Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
      Cc: stable <stable@vger.kernel.org>
      Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      493f7583
    • Samir Virmani's avatar
      uart: Fix crash in uart_write and uart_put_char · b7bd4a2b
      Samir Virmani authored
      commit aff9cf59 upstream.
      
      We were experiencing a crash similar to the one reported as part of
      commit:a5ba1d95 ("uart: fix race between uart_put_char() and
      uart_shutdown()") in our testbed as well. We continue to observe the same
      crash after integrating the commit a5ba1d95 ("uart: fix race between
      uart_put_char() and uart_shutdown()")
      
      On reviewing the change, the port lock should be taken prior to checking for
      if (!circ->buf) in fn. __uart_put_char and other fns. that update the buffer
      uart_state->xmit.
      
      Traceback:
      
      [11/27/2018 06:24:32.4870] Unable to handle kernel NULL pointer dereference
                                 at virtual address 0000003b
      
      [11/27/2018 06:24:32.4950] PC is at memcpy+0x48/0x180
      [11/27/2018 06:24:32.4950] LR is at uart_write+0x74/0x120
      [11/27/2018 06:24:32.4950] pc : [<ffffffc0002e6808>]
                                 lr : [<ffffffc0003747cc>] pstate: 000001c5
      [11/27/2018 06:24:32.4950] sp : ffffffc076433d30
      [11/27/2018 06:24:32.4950] x29: ffffffc076433d30 x28: 0000000000000140
      [11/27/2018 06:24:32.4950] x27: ffffffc0009b9d5e x26: ffffffc07ce36580
      [11/27/2018 06:24:32.4950] x25: 0000000000000000 x24: 0000000000000140
      [11/27/2018 06:24:32.4950] x23: ffffffc000891200 x22: ffffffc01fc34000
      [11/27/2018 06:24:32.4950] x21: 0000000000000fff x20: 0000000000000076
      [11/27/2018 06:24:32.4950] x19: 0000000000000076 x18: 0000000000000000
      [11/27/2018 06:24:32.4950] x17: 000000000047cf08 x16: ffffffc000099e68
      [11/27/2018 06:24:32.4950] x15: 0000000000000018 x14: 776d726966205948
      [11/27/2018 06:24:32.4950] x13: 50203a6c6974755f x12: 74647075205d3333
      [11/27/2018 06:24:32.4950] x11: 3a35323a36203831 x10: 30322f37322f3131
      [11/27/2018 06:24:32.4950] x9 : 5b205d303638342e x8 : 746164206f742070
      [11/27/2018 06:24:32.4950] x7 : 7520736920657261 x6 : 000000000000003b
      [11/27/2018 06:24:32.4950] x5 : 000000000000817a x4 : 0000000000000008
      [11/27/2018 06:24:32.4950] x3 : 2f37322f31312a5b x2 : 000000000000006e
      [11/27/2018 06:24:32.4950] x1 : ffffffc0009b9cf0 x0 : 000000000000003b
      
      [11/27/2018 06:24:32.4950] CPU2: stopping
      [11/27/2018 06:24:32.4950] CPU: 2 PID: 0 Comm: swapper/2 Tainted: P      D    O    4.1.51 #3
      [11/27/2018 06:24:32.4950] Hardware name: Broadcom-v8A (DT)
      [11/27/2018 06:24:32.4950] Call trace:
      [11/27/2018 06:24:32.4950] [<ffffffc0000883b8>] dump_backtrace+0x0/0x150
      [11/27/2018 06:24:32.4950] [<ffffffc00008851c>] show_stack+0x14/0x20
      [11/27/2018 06:24:32.4950] [<ffffffc0005ee810>] dump_stack+0x90/0xb0
      [11/27/2018 06:24:32.4950] [<ffffffc00008e844>] handle_IPI+0x18c/0x1a0
      [11/27/2018 06:24:32.4950] [<ffffffc000080c68>] gic_handle_irq+0x88/0x90
      
      Fixes: a5ba1d95 ("uart: fix race between uart_put_char() and uart_shutdown()")
      Cc: stable <stable@vger.kernel.org>
      Signed-off-by: default avatarSamir Virmani <samir@embedur.com>
      Acked-by: default avatarTycho Andersen <tycho@tycho.ws>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b7bd4a2b
    • Greg Kroah-Hartman's avatar
      tty: Handle problem if line discipline does not have receive_buf · 0609c032
      Greg Kroah-Hartman authored
      commit 27cfb3a5 upstream.
      
      Some tty line disciplines do not have a receive buf callback, so
      properly check for that before calling it.  If they do not have this
      callback, just eat the character quietly, as we can't fail this call.
      Reported-by: default avatarJann Horn <jannh@google.com>
      Cc: stable <stable@vger.kernel.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      0609c032
    • Michael Straube's avatar
      staging: rtl8188eu: Add device code for D-Link DWA-121 rev B1 · dff6b7b3
      Michael Straube authored
      commit 5f74a8cb upstream.
      
      This device was added to the stand-alone driver on github.
      Add it to the staging driver as well.
      
      Link: https://github.com/lwfinger/rtl8188eu/commit/a0619a07cd1eSigned-off-by: default avatarMichael Straube <straube.linux@gmail.com>
      Acked-by: default avatarLarry Finger <Larry.Finger@lwfinger.net>
      Cc: stable <stable@vger.kernel.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      dff6b7b3
    • Gustavo A. R. Silva's avatar
      char/mwave: fix potential Spectre v1 vulnerability · 08e4f6c4
      Gustavo A. R. Silva authored
      commit 701956d4 upstream.
      
      ipcnum is indirectly controlled by user-space, hence leading to
      a potential exploitation of the Spectre variant 1 vulnerability.
      
      This issue was detected with the help of Smatch:
      
      drivers/char/mwave/mwavedd.c:299 mwave_ioctl() warn: potential spectre issue 'pDrvData->IPCs' [w] (local cap)
      
      Fix this by sanitizing ipcnum before using it to index pDrvData->IPCs.
      
      Notice that given that speculation windows are large, the policy is
      to kill the speculation on the first load and not worry if it can be
      completed with a dependent load/store [1].
      
      [1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2
      
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarGustavo A. R. Silva <gustavo@embeddedor.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      08e4f6c4
    • Gerald Schaefer's avatar
      s390/smp: fix CPU hotplug deadlock with CPU rescan · 7ed458fd
      Gerald Schaefer authored
      commit b7cb707c upstream.
      
      smp_rescan_cpus() is called without the device_hotplug_lock, which can lead
      to a dedlock when a new CPU is found and immediately set online by a udev
      rule.
      
      This was observed on an older kernel version, where the cpu_hotplug_begin()
      loop was still present, and it resulted in hanging chcpu and systemd-udev
      processes. This specific deadlock will not show on current kernels. However,
      there may be other possible deadlocks, and since smp_rescan_cpus() can still
      trigger a CPU hotplug operation, the device_hotplug_lock should be held.
      
      For reference, this was the deadlock with the old cpu_hotplug_begin() loop:
      
              chcpu (rescan)                       systemd-udevd
      
       echo 1 > /sys/../rescan
       -> smp_rescan_cpus()
       -> (*) get_online_cpus()
          (increases refcount)
       -> smp_add_present_cpu()
          (new CPU found)
       -> register_cpu()
       -> device_add()
       -> udev "add" event triggered -----------> udev rule sets CPU online
                                               -> echo 1 > /sys/.../online
                                               -> lock_device_hotplug_sysfs()
                                                  (this is missing in rescan path)
                                               -> device_online()
                                               -> (**) device_lock(new CPU dev)
                                               -> cpu_up()
                                               -> cpu_hotplug_begin()
                                                  (loops until refcount == 0)
                                                  -> deadlock with (*)
       -> bus_probe_device()
       -> device_attach()
       -> device_lock(new CPU dev)
          -> deadlock with (**)
      
      Fix this by taking the device_hotplug_lock in the CPU rescan path.
      
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarGerald Schaefer <gerald.schaefer@de.ibm.com>
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      7ed458fd
    • Christian Borntraeger's avatar
      s390/early: improve machine detection · 17eb3c3e
      Christian Borntraeger authored
      commit 03aa047e upstream.
      
      Right now the early machine detection code check stsi 3.2.2 for "KVM"
      and set MACHINE_IS_VM if this is different. As the console detection
      uses diagnose 8 if MACHINE_IS_VM returns true this will crash Linux
      early for any non z/VM system that sets a different value than KVM.
      So instead of assuming z/VM, do not set any of MACHINE_IS_LPAR,
      MACHINE_IS_VM, or MACHINE_IS_KVM.
      
      CC: stable@vger.kernel.org
      Reviewed-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      Signed-off-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      17eb3c3e
    • Eugeniy Paltsev's avatar
      ARC: perf: map generic branches to correct hardware condition · d8940899
      Eugeniy Paltsev authored
      commit 3affbf0e upstream.
      
      So far we've mapped branches to "ijmp" which also counts conditional
      branches NOT taken. This makes us different from other architectures
      such as ARM which seem to be counting only taken branches.
      
      So use "ijmptak" hardware condition which only counts (all jump
      instructions that are taken)
      
      'ijmptak' event is available on both ARCompact and ARCv2 ISA based
      cores.
      Signed-off-by: default avatarEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarVineet Gupta <vgupta@synopsys.com>
      [vgupta: reworked changelog]
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      d8940899
    • Eugeniy Paltsev's avatar
      ARCv2: lib: memeset: fix doing prefetchw outside of buffer · 5a026d14
      Eugeniy Paltsev authored
      commit e6a72b7d upstream.
      
      ARCv2 optimized memset uses PREFETCHW instruction for prefetching the
      next cache line but doesn't ensure that the line is not past the end of
      the buffer. PRETECHW changes the line ownership and marks it dirty,
      which can cause issues in SMP config when next line was already owned by
      other core. Fix the issue by avoiding the PREFETCHW
      
      Some more details:
      
      The current code has 3 logical loops (ignroing the unaligned part)
        (a) Big loop for doing aligned 64 bytes per iteration with PREALLOC
        (b) Loop for 32 x 2 bytes with PREFETCHW
        (c) any left over bytes
      
      loop (a) was already eliding the last 64 bytes, so PREALLOC was
      safe. The fix was removing PREFETCW from (b).
      
      Another potential issue (applicable to configs with 32 or 128 byte L1
      cache line) is that PREALLOC assumes 64 byte cache line and may not do
      the right thing specially for 32b. While it would be easy to adapt,
      there are no known configs with those lie sizes, so for now, just
      compile out PREALLOC in such cases.
      Signed-off-by: default avatarEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
      Cc: stable@vger.kernel.org #4.4+
      Signed-off-by: default avatarVineet Gupta <vgupta@synopsys.com>
      [vgupta: rewrote changelog, used asm .macro vs. "C" macro]
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      5a026d14
    • Gustavo A. R. Silva's avatar
      ASoC: rt5514-spi: Fix potential NULL pointer dereference · 9b65b52e
      Gustavo A. R. Silva authored
      commit 060d0bf4 upstream.
      
      There is a potential NULL pointer dereference in case devm_kzalloc()
      fails and returns NULL.
      
      Fix this by adding a NULL check on rt5514_dsp.
      
      This issue was detected with the help of Coccinelle.
      
      Fixes: 6eebf35b ("ASoC: rt5514: add rt5514 SPI driver")
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarGustavo A. R. Silva <gustavo@embeddedor.com>
      Signed-off-by: default avatarMark Brown <broonie@kernel.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      9b65b52e
    • Kangjie Lu's avatar
      ASoC: atom: fix a missing check of snd_pcm_lib_malloc_pages · 3d963c98
      Kangjie Lu authored
      commit 44fabd8c upstream.
      
      snd_pcm_lib_malloc_pages() may fail, so let's check its status and
      return its error code upstream.
      Signed-off-by: default avatarKangjie Lu <kjlu@umn.edu>
      Acked-by: default avatarPierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
      Signed-off-by: default avatarMark Brown <broonie@kernel.org>
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      3d963c98
    • Charles Yeh's avatar
      USB: serial: pl2303: add new PID to support PL2303TB · efccd43d
      Charles Yeh authored
      commit 4dcf9ddc upstream.
      
      Add new PID to support PL2303TB (TYPE_HX)
      Signed-off-by: default avatarCharles Yeh <charlesyeh522@gmail.com>
      Cc: stable <stable@vger.kernel.org>
      Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      efccd43d
    • Max Schulze's avatar
      USB: serial: simple: add Motorola Tetra TPG2200 device id · da062938
      Max Schulze authored
      commit b81c2c33 upstream.
      
      Add new Motorola Tetra device id for Motorola Solutions TETRA PEI device
      
      T:  Bus=02 Lev=01 Prnt=01 Port=01 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=0cad ProdID=9016 Rev=24.16
      S:  Manufacturer=Motorola Solutions, Inc.
      S:  Product=TETRA PEI interface
      C:  #Ifs= 2 Cfg#= 1 Atr=80 MxPwr=500mA
      I:  If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=00 Prot=00 Driver=usb_serial_simple
      I:  If#= 1 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=00 Prot=00 Driver=usb_serial_simple
      Signed-off-by: default avatarMax Schulze <max.schulze@posteo.de>
      Cc: stable <stable@vger.kernel.org>
      Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      da062938
    • Paolo Abeni's avatar
      ipfrag: really prevent allocation on netns exit · 8c849652
      Paolo Abeni authored
      [ Upstream commit f6f2a4a2 ]
      
      Setting the low threshold to 0 has no effect on frags allocation,
      we need to clear high_thresh instead.
      
      The code was pre-existent to commit 648700f7 ("inet: frags:
      use rhashtables for reassembly units"), but before the above,
      such assignment had a different role: prevent concurrent eviction
      from the worker and the netns cleanup helper.
      
      Fixes: 648700f7 ("inet: frags: use rhashtables for reassembly units")
      Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      8c849652
    • Cong Wang's avatar
      net_sched: refetch skb protocol for each filter · 147bb6f5
      Cong Wang authored
      [ Upstream commit cd0c4e70 ]
      
      Martin reported a set of filters don't work after changing
      from reclassify to continue. Looking into the code, it
      looks like skb protocol is not always fetched for each
      iteration of the filters. But, as demonstrated by Martin,
      TC actions could modify skb->protocol, for example act_vlan,
      this means we have to refetch skb protocol in each iteration,
      rather than using the one we fetch in the beginning of the loop.
      
      This bug is _not_ introduced by commit 3b3ae880
      ("net: sched: consolidate tc_classify{,_compat}"), technically,
      if act_vlan is the only action that modifies skb protocol, then
      it is commit c7e2b968 ("sched: introduce vlan action") which
      introduced this bug.
      Reported-by: default avatarMartin Olsson <martin.olsson+netdev@sentorsecurity.com>
      Cc: Jamal Hadi Salim <jhs@mojatatu.com>
      Cc: Jiri Pirko <jiri@resnulli.us>
      Signed-off-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
      Acked-by: default avatarJamal Hadi Salim <jhs@mojatatu.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      147bb6f5
    • Ido Schimmel's avatar
      net: ipv4: Fix memory leak in network namespace dismantle · bff74329
      Ido Schimmel authored
      [ Upstream commit f97f4dd8 ]
      
      IPv4 routing tables are flushed in two cases:
      
      1. In response to events in the netdev and inetaddr notification chains
      2. When a network namespace is being dismantled
      
      In both cases only routes associated with a dead nexthop group are
      flushed. However, a nexthop group will only be marked as dead in case it
      is populated with actual nexthops using a nexthop device. This is not
      the case when the route in question is an error route (e.g.,
      'blackhole', 'unreachable').
      
      Therefore, when a network namespace is being dismantled such routes are
      not flushed and leaked [1].
      
      To reproduce:
      # ip netns add blue
      # ip -n blue route add unreachable 192.0.2.0/24
      # ip netns del blue
      
      Fix this by not skipping error routes that are not marked with
      RTNH_F_DEAD when flushing the routing tables.
      
      To prevent the flushing of such routes in case #1, add a parameter to
      fib_table_flush() that indicates if the table is flushed as part of
      namespace dismantle or not.
      
      Note that this problem does not exist in IPv6 since error routes are
      associated with the loopback device.
      
      [1]
      unreferenced object 0xffff888066650338 (size 56):
        comm "ip", pid 1206, jiffies 4294786063 (age 26.235s)
        hex dump (first 32 bytes):
          00 00 00 00 00 00 00 00 b0 1c 62 61 80 88 ff ff  ..........ba....
          e8 8b a1 64 80 88 ff ff 00 07 00 08 fe 00 00 00  ...d............
        backtrace:
          [<00000000856ed27d>] inet_rtm_newroute+0x129/0x220
          [<00000000fcdfc00a>] rtnetlink_rcv_msg+0x397/0xa20
          [<00000000cb85801a>] netlink_rcv_skb+0x132/0x380
          [<00000000ebc991d2>] netlink_unicast+0x4c0/0x690
          [<0000000014f62875>] netlink_sendmsg+0x929/0xe10
          [<00000000bac9d967>] sock_sendmsg+0xc8/0x110
          [<00000000223e6485>] ___sys_sendmsg+0x77a/0x8f0
          [<000000002e94f880>] __sys_sendmsg+0xf7/0x250
          [<00000000ccb1fa72>] do_syscall_64+0x14d/0x610
          [<00000000ffbe3dae>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
          [<000000003a8b605b>] 0xffffffffffffffff
      unreferenced object 0xffff888061621c88 (size 48):
        comm "ip", pid 1206, jiffies 4294786063 (age 26.235s)
        hex dump (first 32 bytes):
          6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
          6b 6b 6b 6b 6b 6b 6b 6b d8 8e 26 5f 80 88 ff ff  kkkkkkkk..&_....
        backtrace:
          [<00000000733609e3>] fib_table_insert+0x978/0x1500
          [<00000000856ed27d>] inet_rtm_newroute+0x129/0x220
          [<00000000fcdfc00a>] rtnetlink_rcv_msg+0x397/0xa20
          [<00000000cb85801a>] netlink_rcv_skb+0x132/0x380
          [<00000000ebc991d2>] netlink_unicast+0x4c0/0x690
          [<0000000014f62875>] netlink_sendmsg+0x929/0xe10
          [<00000000bac9d967>] sock_sendmsg+0xc8/0x110
          [<00000000223e6485>] ___sys_sendmsg+0x77a/0x8f0
          [<000000002e94f880>] __sys_sendmsg+0xf7/0x250
          [<00000000ccb1fa72>] do_syscall_64+0x14d/0x610
          [<00000000ffbe3dae>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
          [<000000003a8b605b>] 0xffffffffffffffff
      
      Fixes: 8cced9ef ("[NETNS]: Enable routing configuration in non-initial namespace.")
      Signed-off-by: default avatarIdo Schimmel <idosch@mellanox.com>
      Reviewed-by: default avatarDavid Ahern <dsahern@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      bff74329
    • Jason Wang's avatar
      vhost: log dirty page correctly · b35efeb6
      Jason Wang authored
      [ Upstream commit cc5e7107 ]
      
      Vhost dirty page logging API is designed to sync through GPA. But we
      try to log GIOVA when device IOTLB is enabled. This is wrong and may
      lead to missing data after migration.
      
      To solve this issue, when logging with device IOTLB enabled, we will:
      
      1) reuse the device IOTLB translation result of GIOVA->HVA mapping to
         get HVA, for writable descriptor, get HVA through iovec. For used
         ring update, translate its GIOVA to HVA
      2) traverse the GPA->HVA mapping to get the possible GPA and log
         through GPA. Pay attention this reverse mapping is not guaranteed
         to be unique, so we should log each possible GPA in this case.
      
      This fix the failure of scp to guest during migration. In -next, we
      will probably support passing GIOVA->GPA instead of GIOVA->HVA.
      
      Fixes: 6b1e6cc7 ("vhost: new device IOTLB API")
      Reported-by: default avatarJintack Lim <jintack@cs.columbia.edu>
      Cc: Jintack Lim <jintack@cs.columbia.edu>
      Signed-off-by: default avatarJason Wang <jasowang@redhat.com>
      Acked-by: default avatarMichael S. Tsirkin <mst@redhat.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b35efeb6
    • Ross Lagerwall's avatar
      openvswitch: Avoid OOB read when parsing flow nlattrs · 4b9245f2
      Ross Lagerwall authored
      [ Upstream commit 04a4af33 ]
      
      For nested and variable attributes, the expected length of an attribute
      is not known and marked by a negative number.  This results in an OOB
      read when the expected length is later used to check if the attribute is
      all zeros. Fix this by using the actual length of the attribute rather
      than the expected length.
      Signed-off-by: default avatarRoss Lagerwall <ross.lagerwall@citrix.com>
      Acked-by: default avatarPravin B Shelar <pshelar@ovn.org>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      4b9245f2
    • Ross Lagerwall's avatar
      net: Fix usage of pskb_trim_rcsum · 04663e84
      Ross Lagerwall authored
      [ Upstream commit 6c57f045 ]
      
      In certain cases, pskb_trim_rcsum() may change skb pointers.
      Reinitialize header pointers afterwards to avoid potential
      use-after-frees. Add a note in the documentation of
      pskb_trim_rcsum(). Found by KASAN.
      Signed-off-by: default avatarRoss Lagerwall <ross.lagerwall@citrix.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      04663e84
    • Yunjian Wang's avatar
      net: bridge: Fix ethernet header pointer before check skb forwardable · 0ae4bffc
      Yunjian Wang authored
      [ Upstream commit 28c1382f ]
      
      The skb header should be set to ethernet header before using
      is_skb_forwardable. Because the ethernet header length has been
      considered in is_skb_forwardable(including dev->hard_header_len
      length).
      
      To reproduce the issue:
      1, add 2 ports on linux bridge br using following commands:
      $ brctl addbr br
      $ brctl addif br eth0
      $ brctl addif br eth1
      2, the MTU of eth0 and eth1 is 1500
      3, send a packet(Data 1480, UDP 8, IP 20, Ethernet 14, VLAN 4)
      from eth0 to eth1
      
      So the expect result is packet larger than 1500 cannot pass through
      eth0 and eth1. But currently, the packet passes through success, it
      means eth1's MTU limit doesn't take effect.
      
      Fixes: f6367b46 ("bridge: use is_skb_forwardable in forward path")
      Cc: bridge@lists.linux-foundation.org
      Cc: Nkolay Aleksandrov <nikolay@cumulusnetworks.com>
      Cc: Roopa Prabhu <roopa@cumulusnetworks.com>
      Cc: Stephen Hemminger <stephen@networkplumber.org>
      Signed-off-by: default avatarYunjian Wang <wangyunjian@huawei.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      0ae4bffc
  2. 26 Jan, 2019 17 commits
    • Greg Kroah-Hartman's avatar
      Linux 4.9.153 · 189b75ad
      Greg Kroah-Hartman authored
      189b75ad
    • Dave Airlie's avatar
      locking/qspinlock: Pull in asm/byteorder.h to ensure correct endianness · 4b527f25
      Dave Airlie authored
      This commit is not required upstream, but is required for the 4.9.y
      stable series.
      
      Upstream commit 101110f6 ("Kbuild: always define endianess in
      kconfig.h") ensures that either __LITTLE_ENDIAN or __BIG_ENDIAN is
      defined to reflect the endianness of the target CPU architecture
      regardless of whether or not <asm/byteorder.h> has been #included. The
      upstream definition of 'struct qspinlock' relies on this property.
      
      Unfortunately, the 4.9.y stable series does not provide this guarantee,
      so the 'spin_unlock()' routine can erroneously treat the underlying
      lockword as big-endian on little-endian architectures using native
      qspinlock (i.e. x86_64 without PV) if the caller has not included
      <asm/byteorder.h>. This can lead to hangs such as the one in
      'i915_gem_request()' reported via bugzilla:
      
        https://bugzilla.kernel.org/show_bug.cgi?id=202063
      
      Fix the issue by ensuring that <asm/byteorder.h> is #included in
      <asm/qspinlock_types.h>, where 'struct qspinlock' is defined.
      
      Cc: <stable@vger.kernel.org> # 4.9
      Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
      [will: wrote commit message]
      Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      4b527f25
    • Corey Minyard's avatar
      ipmi:ssif: Fix handling of multi-part return messages · cac2590d
      Corey Minyard authored
      commit 7d6380cd upstream.
      
      The block number was not being compared right, it was off by one
      when checking the response.
      
      Some statistics wouldn't be incremented properly in some cases.
      
      Check to see if that middle-part messages always have 31 bytes of
      data.
      Signed-off-by: default avatarCorey Minyard <cminyard@mvista.com>
      Cc: stable@vger.kernel.org # 4.4
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      cac2590d
    • Michal Hocko's avatar
      mm, proc: be more verbose about unstable VMA flags in /proc/<pid>/smaps · 28aeb4c9
      Michal Hocko authored
      [ Upstream commit 7550c607 ]
      
      Patch series "THP eligibility reporting via proc".
      
      This series of three patches aims at making THP eligibility reporting much
      more robust and long term sustainable.  The trigger for the change is a
      regression report [2] and the long follow up discussion.  In short the
      specific application didn't have good API to query whether a particular
      mapping can be backed by THP so it has used VMA flags to workaround that.
      These flags represent a deep internal state of VMAs and as such they
      should be used by userspace with a great deal of caution.
      
      A similar has happened for [3] when users complained that VM_MIXEDMAP is
      no longer set on DAX mappings.  Again a lack of a proper API led to an
      abuse.
      
      The first patch in the series tries to emphasise that that the semantic of
      flags might change and any application consuming those should be really
      careful.
      
      The remaining two patches provide a more suitable interface to address [2]
      and provide a consistent API to query the THP status both for each VMA and
      process wide as well.  [1]
      
      http://lkml.kernel.org/r/20181120103515.25280-1-mhocko@kernel.org [2]
      http://lkml.kernel.org/r/http://lkml.kernel.org/r/alpine.DEB.2.21.1809241054050.224429@chino.kir.corp.google.com
      [3] http://lkml.kernel.org/r/20181002100531.GC4135@quack2.suse.cz
      
      This patch (of 3):
      
      Even though vma flags exported via /proc/<pid>/smaps are explicitly
      documented to be not guaranteed for future compatibility the warning
      doesn't go far enough because it doesn't mention semantic changes to those
      flags.  And they are important as well because these flags are a deep
      implementation internal to the MM code and the semantic might change at
      any time.
      
      Let's consider two recent examples:
      http://lkml.kernel.org/r/20181002100531.GC4135@quack2.suse.cz
      : commit e1fb4a08 "dax: remove VM_MIXEDMAP for fsdax and device dax" has
      : removed VM_MIXEDMAP flag from DAX VMAs. Now our testing shows that in the
      : mean time certain customer of ours started poking into /proc/<pid>/smaps
      : and looks at VMA flags there and if VM_MIXEDMAP is missing among the VMA
      : flags, the application just fails to start complaining that DAX support is
      : missing in the kernel.
      
      http://lkml.kernel.org/r/alpine.DEB.2.21.1809241054050.224429@chino.kir.corp.google.com
      : Commit 18600332 ("mm: make PR_SET_THP_DISABLE immediately active")
      : introduced a regression in that userspace cannot always determine the set
      : of vmas where thp is ineligible.
      : Userspace relies on the "nh" flag being emitted as part of /proc/pid/smaps
      : to determine if a vma is eligible to be backed by hugepages.
      : Previous to this commit, prctl(PR_SET_THP_DISABLE, 1) would cause thp to
      : be disabled and emit "nh" as a flag for the corresponding vmas as part of
      : /proc/pid/smaps.  After the commit, thp is disabled by means of an mm
      : flag and "nh" is not emitted.
      : This causes smaps parsing libraries to assume a vma is eligible for thp
      : and ends up puzzling the user on why its memory is not backed by thp.
      
      In both cases userspace was relying on a semantic of a specific VMA flag.
      The primary reason why that happened is a lack of a proper interface.
      While this has been worked on and it will be fixed properly, it seems that
      our wording could see some refinement and be more vocal about semantic
      aspect of these flags as well.
      
      Link: http://lkml.kernel.org/r/20181211143641.3503-2-mhocko@kernel.orgSigned-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Acked-by: default avatarJan Kara <jack@suse.cz>
      Acked-by: default avatarDan Williams <dan.j.williams@intel.com>
      Acked-by: default avatarDavid Rientjes <rientjes@google.com>
      Acked-by: default avatarMike Rapoport <rppt@linux.ibm.com>
      Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Paul Oppenheimer <bepvte@gmail.com>
      Cc: William Kucharski <william.kucharski@oracle.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      28aeb4c9
    • Brian Foster's avatar
      mm/page-writeback.c: don't break integrity writeback on ->writepage() error · c6e4be62
      Brian Foster authored
      [ Upstream commit 3fa750dc ]
      
      write_cache_pages() is used in both background and integrity writeback
      scenarios by various filesystems.  Background writeback is mostly
      concerned with cleaning a certain number of dirty pages based on various
      mm heuristics.  It may not write the full set of dirty pages or wait for
      I/O to complete.  Integrity writeback is responsible for persisting a set
      of dirty pages before the writeback job completes.  For example, an
      fsync() call must perform integrity writeback to ensure data is on disk
      before the call returns.
      
      write_cache_pages() unconditionally breaks out of its processing loop in
      the event of a ->writepage() error.  This is fine for background
      writeback, which had no strict requirements and will eventually come
      around again.  This can cause problems for integrity writeback on
      filesystems that might need to clean up state associated with failed page
      writeouts.  For example, XFS performs internal delayed allocation
      accounting before returning a ->writepage() error, where applicable.  If
      the current writeback happens to be associated with an unmount and
      write_cache_pages() completes the writeback prematurely due to error, the
      filesystem is unmounted in an inconsistent state if dirty+delalloc pages
      still exist.
      
      To handle this problem, update write_cache_pages() to always process the
      full set of pages for integrity writeback regardless of ->writepage()
      errors.  Save the first encountered error and return it to the caller once
      complete.  This facilitates XFS (or any other fs that expects integrity
      writeback to process the entire set of dirty pages) to clean up its
      internal state completely in the event of persistent mapping errors.
      Background writeback continues to exit on the first error encountered.
      
      [akpm@linux-foundation.org: fix typo in comment]
      Link: http://lkml.kernel.org/r/20181116134304.32440-1-bfoster@redhat.comSigned-off-by: default avatarBrian Foster <bfoster@redhat.com>
      Reviewed-by: default avatarJan Kara <jack@suse.cz>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      c6e4be62
    • Junxiao Bi's avatar
      ocfs2: fix panic due to unrecovered local alloc · 3cc44695
      Junxiao Bi authored
      [ Upstream commit 532e1e54 ]
      
      mount.ocfs2 ignore the inconsistent error that journal is clean but
      local alloc is unrecovered.  After mount, local alloc not empty, then
      reserver cluster didn't alloc a new local alloc window, reserveration
      map is empty(ocfs2_reservation_map.m_bitmap_len = 0), that triggered the
      following panic.
      
      This issue was reported at
      
        https://oss.oracle.com/pipermail/ocfs2-devel/2015-May/010854.html
      
      and was advised to fixed during mount.  But this is a very unusual
      inconsistent state, usually journal dirty flag should be cleared at the
      last stage of umount until every other things go right.  We may need do
      further debug to check that.  Any way to avoid possible futher
      corruption, mount should be abort and fsck should be run.
      
        (mount.ocfs2,1765,1):ocfs2_load_local_alloc:353 ERROR: Local alloc hasn't been recovered!
        found = 6518, set = 6518, taken = 8192, off = 15912372
        ocfs2: Mounting device (202,64) on (node 0, slot 3) with ordered data mode.
        o2dlm: Joining domain 89CEAC63CC4F4D03AC185B44E0EE0F3F ( 0 1 2 3 4 5 6 8 ) 8 nodes
        ocfs2: Mounting device (202,80) on (node 0, slot 3) with ordered data mode.
        o2hb: Region 89CEAC63CC4F4D03AC185B44E0EE0F3F (xvdf) is now a quorum device
        o2net: Accepted connection from node yvwsoa17p (num 7) at 172.22.77.88:7777
        o2dlm: Node 7 joins domain 64FE421C8C984E6D96ED12C55FEE2435 ( 0 1 2 3 4 5 6 7 8 ) 9 nodes
        o2dlm: Node 7 joins domain 89CEAC63CC4F4D03AC185B44E0EE0F3F ( 0 1 2 3 4 5 6 7 8 ) 9 nodes
        ------------[ cut here ]------------
        kernel BUG at fs/ocfs2/reservations.c:507!
        invalid opcode: 0000 [#1] SMP
        Modules linked in: ocfs2 rpcsec_gss_krb5 auth_rpcgss nfsv4 nfs fscache lockd grace ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs sunrpc ipt_REJECT nf_reject_ipv4 nf_conntrack_ipv4 nf_defrag_ipv4 iptable_filter ip_tables ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm ib_sa ib_mad ib_core ib_addr ipv6 ovmapi ppdev parport_pc parport xen_netfront fb_sys_fops sysimgblt sysfillrect syscopyarea acpi_cpufreq pcspkr i2c_piix4 i2c_core sg ext4 jbd2 mbcache2 sr_mod cdrom xen_blkfront pata_acpi ata_generic ata_piix floppy dm_mirror dm_region_hash dm_log dm_mod
        CPU: 0 PID: 4349 Comm: startWebLogic.s Not tainted 4.1.12-124.19.2.el6uek.x86_64 #2
        Hardware name: Xen HVM domU, BIOS 4.4.4OVM 09/06/2018
        task: ffff8803fb04e200 ti: ffff8800ea4d8000 task.ti: ffff8800ea4d8000
        RIP: 0010:[<ffffffffa05e96a8>]  [<ffffffffa05e96a8>] __ocfs2_resv_find_window+0x498/0x760 [ocfs2]
        Call Trace:
          ocfs2_resmap_resv_bits+0x10d/0x400 [ocfs2]
          ocfs2_claim_local_alloc_bits+0xd0/0x640 [ocfs2]
          __ocfs2_claim_clusters+0x178/0x360 [ocfs2]
          ocfs2_claim_clusters+0x1f/0x30 [ocfs2]
          ocfs2_convert_inline_data_to_extents+0x634/0xa60 [ocfs2]
          ocfs2_write_begin_nolock+0x1c6/0x1da0 [ocfs2]
          ocfs2_write_begin+0x13e/0x230 [ocfs2]
          generic_perform_write+0xbf/0x1c0
          __generic_file_write_iter+0x19c/0x1d0
          ocfs2_file_write_iter+0x589/0x1360 [ocfs2]
          __vfs_write+0xb8/0x110
          vfs_write+0xa9/0x1b0
          SyS_write+0x46/0xb0
          system_call_fastpath+0x18/0xd7
        Code: ff ff 8b 75 b8 39 75 b0 8b 45 c8 89 45 98 0f 84 e5 fe ff ff 45 8b 74 24 18 41 8b 54 24 1c e9 56 fc ff ff 85 c0 0f 85 48 ff ff ff <0f> 0b 48 8b 05 cf c3 de ff 48 ba 00 00 00 00 00 00 00 10 48 85
        RIP   __ocfs2_resv_find_window+0x498/0x760 [ocfs2]
         RSP <ffff8800ea4db668>
        ---[ end trace 566f07529f2edf3c ]---
        Kernel panic - not syncing: Fatal exception
        Kernel Offset: disabled
      
      Link: http://lkml.kernel.org/r/20181121020023.3034-2-junxiao.bi@oracle.comSigned-off-by: default avatarJunxiao Bi <junxiao.bi@oracle.com>
      Reviewed-by: default avatarYiwen Jiang <jiangyiwen@huawei.com>
      Acked-by: default avatarJoseph Qi <jiangqi903@gmail.com>
      Cc: Jun Piao <piaojun@huawei.com>
      Cc: Mark Fasheh <mfasheh@versity.com>
      Cc: Joel Becker <jlbec@evilplan.org>
      Cc: Changwei Ge <ge.changwei@h3c.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      3cc44695
    • Qian Cai's avatar
      scsi: megaraid: fix out-of-bound array accesses · 7e4c9c47
      Qian Cai authored
      [ Upstream commit c7a082e4 ]
      
      UBSAN reported those with MegaRAID SAS-3 3108,
      
      [   77.467308] UBSAN: Undefined behaviour in drivers/scsi/megaraid/megaraid_sas_fp.c:117:32
      [   77.475402] index 255 is out of range for type 'MR_LD_SPAN_MAP [1]'
      [   77.481677] CPU: 16 PID: 333 Comm: kworker/16:1 Not tainted 4.20.0-rc5+ #1
      [   77.488556] Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.50 06/01/2018
      [   77.495791] Workqueue: events work_for_cpu_fn
      [   77.500154] Call trace:
      [   77.502610]  dump_backtrace+0x0/0x2c8
      [   77.506279]  show_stack+0x24/0x30
      [   77.509604]  dump_stack+0x118/0x19c
      [   77.513098]  ubsan_epilogue+0x14/0x60
      [   77.516765]  __ubsan_handle_out_of_bounds+0xfc/0x13c
      [   77.521767]  mr_update_load_balance_params+0x150/0x158 [megaraid_sas]
      [   77.528230]  MR_ValidateMapInfo+0x2cc/0x10d0 [megaraid_sas]
      [   77.533825]  megasas_get_map_info+0x244/0x2f0 [megaraid_sas]
      [   77.539505]  megasas_init_adapter_fusion+0x9b0/0xf48 [megaraid_sas]
      [   77.545794]  megasas_init_fw+0x1ab4/0x3518 [megaraid_sas]
      [   77.551212]  megasas_probe_one+0x2c4/0xbe0 [megaraid_sas]
      [   77.556614]  local_pci_probe+0x7c/0xf0
      [   77.560365]  work_for_cpu_fn+0x34/0x50
      [   77.564118]  process_one_work+0x61c/0xf08
      [   77.568129]  worker_thread+0x534/0xa70
      [   77.571882]  kthread+0x1c8/0x1d0
      [   77.575114]  ret_from_fork+0x10/0x1c
      
      [   89.240332] UBSAN: Undefined behaviour in drivers/scsi/megaraid/megaraid_sas_fp.c:117:32
      [   89.248426] index 255 is out of range for type 'MR_LD_SPAN_MAP [1]'
      [   89.254700] CPU: 16 PID: 95 Comm: kworker/u130:0 Not tainted 4.20.0-rc5+ #1
      [   89.261665] Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.50 06/01/2018
      [   89.268903] Workqueue: events_unbound async_run_entry_fn
      [   89.274222] Call trace:
      [   89.276680]  dump_backtrace+0x0/0x2c8
      [   89.280348]  show_stack+0x24/0x30
      [   89.283671]  dump_stack+0x118/0x19c
      [   89.287167]  ubsan_epilogue+0x14/0x60
      [   89.290835]  __ubsan_handle_out_of_bounds+0xfc/0x13c
      [   89.295828]  MR_LdRaidGet+0x50/0x58 [megaraid_sas]
      [   89.300638]  megasas_build_io_fusion+0xbb8/0xd90 [megaraid_sas]
      [   89.306576]  megasas_build_and_issue_cmd_fusion+0x138/0x460 [megaraid_sas]
      [   89.313468]  megasas_queue_command+0x398/0x3d0 [megaraid_sas]
      [   89.319222]  scsi_dispatch_cmd+0x1dc/0x8a8
      [   89.323321]  scsi_request_fn+0x8e8/0xdd0
      [   89.327249]  __blk_run_queue+0xc4/0x158
      [   89.331090]  blk_execute_rq_nowait+0xf4/0x158
      [   89.335449]  blk_execute_rq+0xdc/0x158
      [   89.339202]  __scsi_execute+0x130/0x258
      [   89.343041]  scsi_probe_and_add_lun+0x2fc/0x1488
      [   89.347661]  __scsi_scan_target+0x1cc/0x8c8
      [   89.351848]  scsi_scan_channel.part.3+0x8c/0xc0
      [   89.356382]  scsi_scan_host_selected+0x130/0x1f0
      [   89.361002]  do_scsi_scan_host+0xd8/0xf0
      [   89.364927]  do_scan_async+0x9c/0x320
      [   89.368594]  async_run_entry_fn+0x138/0x420
      [   89.372780]  process_one_work+0x61c/0xf08
      [   89.376793]  worker_thread+0x13c/0xa70
      [   89.380546]  kthread+0x1c8/0x1d0
      [   89.383778]  ret_from_fork+0x10/0x1c
      
      This is because when populating Driver Map using firmware raid map, all
      non-existing VDs set their ldTgtIdToLd to 0xff, so it can be skipped later.
      
      From drivers/scsi/megaraid/megaraid_sas_base.c ,
      memset(instance->ld_ids, 0xff, MEGASAS_MAX_LD_IDS);
      
      From drivers/scsi/megaraid/megaraid_sas_fp.c ,
      /* For non existing VDs, iterate to next VD*/
      if (ld >= (MAX_LOGICAL_DRIVES_EXT - 1))
      	continue;
      
      However, there are a few places that failed to skip those non-existing VDs
      due to off-by-one errors. Then, those 0xff leaked into MR_LdRaidGet(0xff,
      map) and triggered the out-of-bound accesses.
      
      Fixes: 51087a86 ("megaraid_sas : Extended VD support")
      Signed-off-by: default avatarQian Cai <cai@lca.pw>
      Acked-by: default avatarSumit Saxena <sumit.saxena@broadcom.com>
      Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      7e4c9c47
    • Kevin Barnett's avatar
      scsi: smartpqi: correct lun reset issues · 1da52f24
      Kevin Barnett authored
      [ Upstream commit 2ba55c98 ]
      
      Problem:
      The Linux kernel takes a logical volume offline after a LUN reset.  This is
      generally accompanied by this message in the dmesg output:
      
      Device offlined - not ready after error recovery
      
      Root Cause:
      The root cause is a "quirk" in the timeout handling in the Linux SCSI
      layer. The Linux kernel places a 30-second timeout on most media access
      commands (reads and writes) that it send to device drivers.  When a media
      access command times out, the Linux kernel goes into error recovery mode
      for the LUN that was the target of the command that timed out. Every
      command that timed out is kept on a list inside of the Linux kernel to be
      retried later. The kernel attempts to recover the command(s) that timed out
      by issuing a LUN reset followed by a TEST UNIT READY. If the LUN reset and
      TEST UNIT READY commands are successful, the kernel retries the command(s)
      that timed out.
      
      Each SCSI command issued by the kernel has a result field associated with
      it. This field indicates the final result of the command (success or
      error). When a command times out, the kernel places a value in this result
      field indicating that the command timed out.
      
      The "quirk" is that after the LUN reset and TEST UNIT READY commands are
      completed, the kernel checks each command on the timed-out command list
      before retrying it. If the result field is still "timed out", the kernel
      treats that command as not having been successfully recovered for a
      retry. If the number of commands that are in this state are greater than
      two, the kernel takes the LUN offline.
      
      Fix:
      When our RAIDStack receives a LUN reset, it simply waits until all
      outstanding commands complete. Generally, all of these outstanding commands
      complete successfully. Therefore, the fix in the smartpqi driver is to
      always set the command result field to indicate success when a request
      completes successfully. This normally isn’t necessary because the result
      field is always initialized to success when the command is submitted to the
      driver. So when the command completes successfully, the result field is
      left untouched. But in this case, the kernel changes the result field
      behind the driver’s back and then expects the field to be changed by the
      driver as the commands that timed-out complete.
      Reviewed-by: default avatarDave Carroll <david.carroll@microsemi.com>
      Reviewed-by: default avatarScott Teel <scott.teel@microsemi.com>
      Signed-off-by: default avatarKevin Barnett <kevin.barnett@microsemi.com>
      Signed-off-by: default avatarDon Brace <don.brace@microsemi.com>
      Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      1da52f24
    • Daniel Vetter's avatar
      sysfs: Disable lockdep for driver bind/unbind files · 54e6f64e
      Daniel Vetter authored
      [ Upstream commit 4f4b3743 ]
      
      This is the much more correct fix for my earlier attempt at:
      
      https://lkml.org/lkml/2018/12/10/118
      
      Short recap:
      
      - There's not actually a locking issue, it's just lockdep being a bit
        too eager to complain about a possible deadlock.
      
      - Contrary to what I claimed the real problem is recursion on
        kn->count. Greg pointed me at sysfs_break_active_protection(), used
        by the scsi subsystem to allow a sysfs file to unbind itself. That
        would be a real deadlock, which isn't what's happening here. Also,
        breaking the active protection means we'd need to manually handle
        all the lifetime fun.
      
      - With Rafael we discussed the task_work approach, which kinda works,
        but has two downsides: It's a functional change for a lockdep
        annotation issue, and it won't work for the bind file (which needs
        to get the errno from the driver load function back to userspace).
      
      - Greg also asked why this never showed up: To hit this you need to
        unregister a 2nd driver from the unload code of your first driver. I
        guess only gpus do that. The bug has always been there, but only
        with a recent patch series did we add more locks so that lockdep
        built a chain from unbinding the snd-hda driver to the
        acpi_video_unregister call.
      
      Full lockdep splat:
      
      [12301.898799] ============================================
      [12301.898805] WARNING: possible recursive locking detected
      [12301.898811] 4.20.0-rc7+ #84 Not tainted
      [12301.898815] --------------------------------------------
      [12301.898821] bash/5297 is trying to acquire lock:
      [12301.898826] 00000000f61c6093 (kn->count#39){++++}, at: kernfs_remove_by_name_ns+0x3b/0x80
      [12301.898841] but task is already holding lock:
      [12301.898847] 000000005f634021 (kn->count#39){++++}, at: kernfs_fop_write+0xdc/0x190
      [12301.898856] other info that might help us debug this:
      [12301.898862]  Possible unsafe locking scenario:
      [12301.898867]        CPU0
      [12301.898870]        ----
      [12301.898874]   lock(kn->count#39);
      [12301.898879]   lock(kn->count#39);
      [12301.898883] *** DEADLOCK ***
      [12301.898891]  May be due to missing lock nesting notation
      [12301.898899] 5 locks held by bash/5297:
      [12301.898903]  #0: 00000000cd800e54 (sb_writers#4){.+.+}, at: vfs_write+0x17f/0x1b0
      [12301.898915]  #1: 000000000465e7c2 (&of->mutex){+.+.}, at: kernfs_fop_write+0xd3/0x190
      [12301.898925]  #2: 000000005f634021 (kn->count#39){++++}, at: kernfs_fop_write+0xdc/0x190
      [12301.898936]  #3: 00000000414ef7ac (&dev->mutex){....}, at: device_release_driver_internal+0x34/0x240
      [12301.898950]  #4: 000000003218fbdf (register_count_mutex){+.+.}, at: acpi_video_unregister+0xe/0x40
      [12301.898960] stack backtrace:
      [12301.898968] CPU: 1 PID: 5297 Comm: bash Not tainted 4.20.0-rc7+ #84
      [12301.898974] Hardware name: Hewlett-Packard HP EliteBook 8460p/161C, BIOS 68SCF Ver. F.01 03/11/2011
      [12301.898982] Call Trace:
      [12301.898989]  dump_stack+0x67/0x9b
      [12301.898997]  __lock_acquire+0x6ad/0x1410
      [12301.899003]  ? kernfs_remove_by_name_ns+0x3b/0x80
      [12301.899010]  ? find_held_lock+0x2d/0x90
      [12301.899017]  ? mutex_spin_on_owner+0xe4/0x150
      [12301.899023]  ? find_held_lock+0x2d/0x90
      [12301.899030]  ? lock_acquire+0x90/0x180
      [12301.899036]  lock_acquire+0x90/0x180
      [12301.899042]  ? kernfs_remove_by_name_ns+0x3b/0x80
      [12301.899049]  __kernfs_remove+0x296/0x310
      [12301.899055]  ? kernfs_remove_by_name_ns+0x3b/0x80
      [12301.899060]  ? kernfs_name_hash+0xd/0x80
      [12301.899066]  ? kernfs_find_ns+0x6c/0x100
      [12301.899073]  kernfs_remove_by_name_ns+0x3b/0x80
      [12301.899080]  bus_remove_driver+0x92/0xa0
      [12301.899085]  acpi_video_unregister+0x24/0x40
      [12301.899127]  i915_driver_unload+0x42/0x130 [i915]
      [12301.899160]  i915_pci_remove+0x19/0x30 [i915]
      [12301.899169]  pci_device_remove+0x36/0xb0
      [12301.899176]  device_release_driver_internal+0x185/0x240
      [12301.899183]  unbind_store+0xaf/0x180
      [12301.899189]  kernfs_fop_write+0x104/0x190
      [12301.899195]  __vfs_write+0x31/0x180
      [12301.899203]  ? rcu_read_lock_sched_held+0x6f/0x80
      [12301.899209]  ? rcu_sync_lockdep_assert+0x29/0x50
      [12301.899216]  ? __sb_start_write+0x13c/0x1a0
      [12301.899221]  ? vfs_write+0x17f/0x1b0
      [12301.899227]  vfs_write+0xb9/0x1b0
      [12301.899233]  ksys_write+0x50/0xc0
      [12301.899239]  do_syscall_64+0x4b/0x180
      [12301.899247]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
      [12301.899253] RIP: 0033:0x7f452ac7f7a4
      [12301.899259] Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 80 00 00 00 00 8b 05 aa f0 2c 00 48 63 ff 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 f3 c3 66 90 55 53 48 89 d5 48 89 f3 48 83
      [12301.899273] RSP: 002b:00007ffceafa6918 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
      [12301.899282] RAX: ffffffffffffffda RBX: 000000000000000d RCX: 00007f452ac7f7a4
      [12301.899288] RDX: 000000000000000d RSI: 00005612a1abf7c0 RDI: 0000000000000001
      [12301.899295] RBP: 00005612a1abf7c0 R08: 000000000000000a R09: 00005612a1c46730
      [12301.899301] R10: 000000000000000a R11: 0000000000000246 R12: 000000000000000d
      [12301.899308] R13: 0000000000000001 R14: 00007f452af4a740 R15: 000000000000000d
      
      Looking around I've noticed that usb and i2c already handle similar
      recursion problems, where a sysfs file can unbind the same type of
      sysfs somewhere else in the hierarchy. Relevant commits are:
      
      commit 356c05d5
      Author: Alan Stern <stern@rowland.harvard.edu>
      Date:   Mon May 14 13:30:03 2012 -0400
      
          sysfs: get rid of some lockdep false positives
      
      commit e9b526fe
      Author: Alexander Sverdlin <alexander.sverdlin@nsn.com>
      Date:   Fri May 17 14:56:35 2013 +0200
      
          i2c: suppress lockdep warning on delete_device
      
      Implement the same trick for driver bind/unbind.
      
      v2: Put the macro into bus.c (Greg).
      Reviewed-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      Cc: Ramalingam C <ramalingam.c@intel.com>
      Cc: Arend van Spriel <aspriel@gmail.com>
      Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
      Cc: Geert Uytterhoeven <geert+renesas@glider.be>
      Cc: Bartosz Golaszewski <brgl@bgdev.pl>
      Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
      Cc: Vivek Gautam <vivek.gautam@codeaurora.org>
      Cc: Joe Perches <joe@perches.com>
      Signed-off-by: default avatarDaniel Vetter <daniel.vetter@intel.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      54e6f64e
    • Takashi Sakamoto's avatar
      ALSA: bebob: fix model-id of unit for Apogee Ensemble · d9c8a99f
      Takashi Sakamoto authored
      [ Upstream commit 644b2e97 ]
      
      This commit fixes hard-coded model-id for an unit of Apogee Ensemble with
      a correct value. This unit uses DM1500 ASIC produced ArchWave AG (formerly
      known as BridgeCo AG).
      
      I note that this model supports three modes in the number of data channels
      in tx/rx streams; 8 ch pairs, 10 ch pairs, 18 ch pairs. The mode is
      switched by Vendor-dependent AV/C command, like:
      
      $ cd linux-firewire-utils
      $ ./firewire-request /dev/fw1 fcp 0x00ff000003dbeb0600000000 (8ch pairs)
      $ ./firewire-request /dev/fw1 fcp 0x00ff000003dbeb0601000000 (10ch pairs)
      $ ./firewire-request /dev/fw1 fcp 0x00ff000003dbeb0602000000 (18ch pairs)
      
      When switching between different mode, the unit disappears from IEEE 1394
      bus, then appears on the bus with different combination of stream formats.
      In a mode of 18 ch pairs, available sampling rate is up to 96.0 kHz, else
      up to 192.0 kHz.
      
      $ ./hinawa-config-rom-printer /dev/fw1
      { 'bus-info': { 'adj': False,
                      'bmc': True,
                      'chip_ID': 21474898341,
                      'cmc': True,
                      'cyc_clk_acc': 100,
                      'generation': 2,
                      'imc': True,
                      'isc': True,
                      'link_spd': 2,
                      'max_ROM': 1,
                      'max_rec': 512,
                      'name': '1394',
                      'node_vendor_ID': 987,
                      'pmc': False},
        'root-directory': [ ['HARDWARE_VERSION', 19],
                            [ 'NODE_CAPABILITIES',
                              { 'addressing': {'64': True, 'fix': True, 'prv': False},
                                'misc': {'int': False, 'ms': False, 'spt': True},
                                'state': { 'atn': False,
                                           'ded': False,
                                           'drq': True,
                                           'elo': False,
                                           'init': False,
                                           'lst': True,
                                           'off': False},
                                'testing': {'bas': False, 'ext': False}}],
                            ['VENDOR', 987],
                            ['DESCRIPTOR', 'Apogee Electronics'],
                            ['MODEL', 126702],
                            ['DESCRIPTOR', 'Ensemble'],
                            ['VERSION', 5297],
                            [ 'UNIT',
                              [ ['SPECIFIER_ID', 41005],
                                ['VERSION', 65537],
                                ['MODEL', 126702],
                                ['DESCRIPTOR', 'Ensemble']]],
                            [ 'DEPENDENT_INFO',
                              [ ['SPECIFIER_ID', 2037],
                                ['VERSION', 1],
                                [(58, 'IMMEDIATE'), 16777159],
                                [(59, 'IMMEDIATE'), 1048576],
                                [(60, 'IMMEDIATE'), 16777159],
                                [(61, 'IMMEDIATE'), 6291456]]]]}
      Signed-off-by: default avatarTakashi Sakamoto <o-takashi@sakamocchi.jp>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      d9c8a99f
    • Nikos Tsironis's avatar
      dm snapshot: Fix excessive memory usage and workqueue stalls · 69855b55
      Nikos Tsironis authored
      [ Upstream commit 721b1d98 ]
      
      kcopyd has no upper limit to the number of jobs one can allocate and
      issue. Under certain workloads this can lead to excessive memory usage
      and workqueue stalls. For example, when creating multiple dm-snapshot
      targets with a 4K chunk size and then writing to the origin through the
      page cache. Syncing the page cache causes a large number of BIOs to be
      issued to the dm-snapshot origin target, which itself issues an even
      larger (because of the BIO splitting taking place) number of kcopyd
      jobs.
      
      Running the following test, from the device mapper test suite [1],
      
        dmtest run --suite snapshot -n many_snapshots_of_same_volume_N
      
      , with 8 active snapshots, results in the kcopyd job slab cache growing
      to 10G. Depending on the available system RAM this can lead to the OOM
      killer killing user processes:
      
      [463.492878] kthreadd invoked oom-killer: gfp_mask=0x6040c0(GFP_KERNEL|__GFP_COMP),
                    nodemask=(null), order=1, oom_score_adj=0
      [463.492894] kthreadd cpuset=/ mems_allowed=0
      [463.492948] CPU: 7 PID: 2 Comm: kthreadd Not tainted 4.19.0-rc7 #3
      [463.492950] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
      [463.492952] Call Trace:
      [463.492964]  dump_stack+0x7d/0xbb
      [463.492973]  dump_header+0x6b/0x2fc
      [463.492987]  ? lockdep_hardirqs_on+0xee/0x190
      [463.493012]  oom_kill_process+0x302/0x370
      [463.493021]  out_of_memory+0x113/0x560
      [463.493030]  __alloc_pages_slowpath+0xf40/0x1020
      [463.493055]  __alloc_pages_nodemask+0x348/0x3c0
      [463.493067]  cache_grow_begin+0x81/0x8b0
      [463.493072]  ? cache_grow_begin+0x874/0x8b0
      [463.493078]  fallback_alloc+0x1e4/0x280
      [463.493092]  kmem_cache_alloc_node+0xd6/0x370
      [463.493098]  ? copy_process.part.31+0x1c5/0x20d0
      [463.493105]  copy_process.part.31+0x1c5/0x20d0
      [463.493115]  ? __lock_acquire+0x3cc/0x1550
      [463.493121]  ? __switch_to_asm+0x34/0x70
      [463.493129]  ? kthread_create_worker_on_cpu+0x70/0x70
      [463.493135]  ? finish_task_switch+0x90/0x280
      [463.493165]  _do_fork+0xe0/0x6d0
      [463.493191]  ? kthreadd+0x19f/0x220
      [463.493233]  kernel_thread+0x25/0x30
      [463.493235]  kthreadd+0x1bf/0x220
      [463.493242]  ? kthread_create_on_cpu+0x90/0x90
      [463.493248]  ret_from_fork+0x3a/0x50
      [463.493279] Mem-Info:
      [463.493285] active_anon:20631 inactive_anon:4831 isolated_anon:0
      [463.493285]  active_file:80216 inactive_file:80107 isolated_file:435
      [463.493285]  unevictable:0 dirty:51266 writeback:109372 unstable:0
      [463.493285]  slab_reclaimable:31191 slab_unreclaimable:3483521
      [463.493285]  mapped:526 shmem:4903 pagetables:1759 bounce:0
      [463.493285]  free:33623 free_pcp:2392 free_cma:0
      ...
      [463.493489] Unreclaimable slab info:
      [463.493513] Name                      Used          Total
      [463.493522] bio-6                   1028KB       1028KB
      [463.493525] bio-5                   1028KB       1028KB
      [463.493528] dm_snap_pending_exception     236783KB     243789KB
      [463.493531] dm_exception              41KB         42KB
      [463.493534] bio-4                   1216KB       1216KB
      [463.493537] bio-3                 439396KB     439396KB
      [463.493539] kcopyd_job           6973427KB    6973427KB
      ...
      [463.494340] Out of memory: Kill process 1298 (ruby2.3) score 1 or sacrifice child
      [463.494673] Killed process 1298 (ruby2.3) total-vm:435740kB, anon-rss:20180kB, file-rss:4kB, shmem-rss:0kB
      [463.506437] oom_reaper: reaped process 1298 (ruby2.3), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB
      
      Moreover, issuing a large number of kcopyd jobs results in kcopyd
      hogging the CPU, while processing them. As a result, processing of work
      items, queued for execution on the same CPU as the currently running
      kcopyd thread, is stalled for long periods of time, hurting performance.
      Running the aforementioned test we get, in dmesg, messages like the
      following:
      
      [67501.194592] BUG: workqueue lockup - pool cpus=4 node=0 flags=0x0 nice=0 stuck for 27s!
      [67501.195586] Showing busy workqueues and worker pools:
      [67501.195591] workqueue events: flags=0x0
      [67501.195597]   pwq 8: cpus=4 node=0 flags=0x0 nice=0 active=1/256
      [67501.195611]     pending: cache_reap
      [67501.195641] workqueue mm_percpu_wq: flags=0x8
      [67501.195645]   pwq 8: cpus=4 node=0 flags=0x0 nice=0 active=1/256
      [67501.195656]     pending: vmstat_update
      [67501.195682] workqueue kblockd: flags=0x18
      [67501.195687]   pwq 5: cpus=2 node=0 flags=0x0 nice=-20 active=1/256
      [67501.195698]     pending: blk_timeout_work
      [67501.195753] workqueue kcopyd: flags=0x8
      [67501.195757]   pwq 8: cpus=4 node=0 flags=0x0 nice=0 active=1/256
      [67501.195768]     pending: do_work [dm_mod]
      [67501.195802] workqueue kcopyd: flags=0x8
      [67501.195806]   pwq 8: cpus=4 node=0 flags=0x0 nice=0 active=1/256
      [67501.195817]     pending: do_work [dm_mod]
      [67501.195834] workqueue kcopyd: flags=0x8
      [67501.195838]   pwq 8: cpus=4 node=0 flags=0x0 nice=0 active=1/256
      [67501.195848]     pending: do_work [dm_mod]
      [67501.195881] workqueue kcopyd: flags=0x8
      [67501.195885]   pwq 8: cpus=4 node=0 flags=0x0 nice=0 active=1/256
      [67501.195896]     pending: do_work [dm_mod]
      [67501.195920] workqueue kcopyd: flags=0x8
      [67501.195924]   pwq 8: cpus=4 node=0 flags=0x0 nice=0 active=2/256
      [67501.195935]     in-flight: 67:do_work [dm_mod]
      [67501.195945]     pending: do_work [dm_mod]
      [67501.195961] pool 8: cpus=4 node=0 flags=0x0 nice=0 hung=27s workers=3 idle: 129 23765
      
      The root cause for these issues is the way dm-snapshot uses kcopyd. In
      particular, the lack of an explicit or implicit limit to the maximum
      number of in-flight COW jobs. The merging path is not affected because
      it implicitly limits the in-flight kcopyd jobs to one.
      
      Fix these issues by using a semaphore to limit the maximum number of
      in-flight kcopyd jobs. We grab the semaphore before allocating a new
      kcopyd job in start_copy() and start_full_bio() and release it after the
      job finishes in copy_callback().
      
      The initial semaphore value is configurable through a module parameter,
      to allow fine tuning the maximum number of in-flight COW jobs. Setting
      this parameter to zero initializes the semaphore to INT_MAX.
      
      A default value of 2048 maximum in-flight kcopyd jobs was chosen. This
      value was decided experimentally as a trade-off between memory
      consumption, stalling the kernel's workqueues and maintaining a high
      enough throughput.
      
      Re-running the aforementioned test:
      
        * Workqueue stalls are eliminated
        * kcopyd's job slab cache uses a maximum of 130MB
        * The time taken by the test to write to the snapshot-origin target is
          reduced from 05m20.48s to 03m26.38s
      
      [1] https://github.com/jthornber/device-mapper-test-suiteSigned-off-by: default avatarNikos Tsironis <ntsironis@arrikto.com>
      Signed-off-by: default avatarIlias Tsitsimpis <iliastsi@arrikto.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      69855b55
    • Arnaldo Carvalho de Melo's avatar
      tools lib subcmd: Don't add the kernel sources to the include path · 7a6da629
      Arnaldo Carvalho de Melo authored
      [ Upstream commit ece98049 ]
      
      At some point we decided not to directly include kernel sources files
      when building tools/perf/, but when tools/lib/subcmd/ was forked from
      tools/perf it somehow ended up adding it via these two lines in its
      Makefile:
      
        CFLAGS += -I$(srctree)/include/uapi
        CFLAGS += -I$(srctree)/include
      
      As $(srctree) points to the kernel sources.
      
      Removing those lines and keeping just:
      
        CFLAGS += -I$(srctree)/tools/include/
      
      Is enough to build tools/perf and tools/objtool.
      
      This fixes the build when building from the sources in environments such
      as the Android NDK crossbuilding from a fedora:26 system:
      
        subcmd-util.h:11:15: error: expected ',' or ';' before 'void'
         static inline void report(const char *prefix, const char *err, va_list params)
                       ^
        In file included from /git/perf/include/uapi/linux/stddef.h:2:0,
                         from /git/perf/include/uapi/linux/posix_types.h:5,
                         from /opt/android-ndk-r12b/platforms/android-24/arch-arm/usr/include/sys/types.h:36,
                         from /opt/android-ndk-r12b/platforms/android-24/arch-arm/usr/include/unistd.h:33,
                         from run-command.c:2:
        subcmd-util.h:18:17: error: '__no_instrument_function__' attribute applies only to functions
      
      The /opt/android-ndk-r12b/platforms/android-24/arch-arm/usr/include/sys/types.h
      file that includes linux/posix_types.h ends up getting the one in the kernel
      sources causing the breakage. Fix it.
      
      Test built tools/objtool/ too.
      Reported-by: default avatarJiri Olsa <jolsa@kernel.org>
      Tested-by: default avatarJiri Olsa <jolsa@kernel.org>
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Fixes: 4b6ab94e ("perf subcmd: Create subcmd library")
      Link: https://lkml.kernel.org/n/tip-5lhaoecrj12t0bqwvpiu14sm@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      7a6da629
    • Nikos Tsironis's avatar
      dm kcopyd: Fix bug causing workqueue stalls · e9566e99
      Nikos Tsironis authored
      [ Upstream commit d7e6b8df ]
      
      When using kcopyd to run callbacks through dm_kcopyd_do_callback() or
      submitting copy jobs with a source size of 0, the jobs are pushed
      directly to the complete_jobs list, which could be under processing by
      the kcopyd thread. As a result, the kcopyd thread can continue running
      completed jobs indefinitely, without releasing the CPU, as long as
      someone keeps submitting new completed jobs through the aforementioned
      paths. Processing of work items, queued for execution on the same CPU as
      the currently running kcopyd thread, is thus stalled for excessive
      amounts of time, hurting performance.
      
      Running the following test, from the device mapper test suite [1],
      
        dmtest run --suite snapshot -n parallel_io_to_many_snaps_N
      
      , with 8 active snapshots, we get, in dmesg, messages like the
      following:
      
      [68899.948523] BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=0 stuck for 95s!
      [68899.949282] Showing busy workqueues and worker pools:
      [68899.949288] workqueue events: flags=0x0
      [68899.949295]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=2/256
      [68899.949306]     pending: vmstat_shepherd, cache_reap
      [68899.949331] workqueue mm_percpu_wq: flags=0x8
      [68899.949337]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256
      [68899.949345]     pending: vmstat_update
      [68899.949387] workqueue dm_bufio_cache: flags=0x8
      [68899.949392]   pwq 4: cpus=2 node=0 flags=0x0 nice=0 active=1/256
      [68899.949400]     pending: work_fn [dm_bufio]
      [68899.949423] workqueue kcopyd: flags=0x8
      [68899.949429]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256
      [68899.949437]     pending: do_work [dm_mod]
      [68899.949452] workqueue kcopyd: flags=0x8
      [68899.949458]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=2/256
      [68899.949466]     in-flight: 13:do_work [dm_mod]
      [68899.949474]     pending: do_work [dm_mod]
      [68899.949487] workqueue kcopyd: flags=0x8
      [68899.949493]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256
      [68899.949501]     pending: do_work [dm_mod]
      [68899.949515] workqueue kcopyd: flags=0x8
      [68899.949521]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256
      [68899.949529]     pending: do_work [dm_mod]
      [68899.949541] workqueue kcopyd: flags=0x8
      [68899.949547]   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256
      [68899.949555]     pending: do_work [dm_mod]
      [68899.949568] pool 0: cpus=0 node=0 flags=0x0 nice=0 hung=95s workers=4 idle: 27130 27223 1084
      
      Fix this by splitting the complete_jobs list into two parts: A user
      facing part, named callback_jobs, and one used internally by kcopyd,
      retaining the name complete_jobs. dm_kcopyd_do_callback() and
      dispatch_job() now push their jobs to the callback_jobs list, which is
      spliced to the complete_jobs list once, every time the kcopyd thread
      wakes up. This prevents kcopyd from hogging the CPU indefinitely and
      causing workqueue stalls.
      
      Re-running the aforementioned test:
      
        * Workqueue stalls are eliminated
        * The maximum writing time among all targets is reduced from 09m37.10s
          to 06m04.85s and the total run time of the test is reduced from
          10m43.591s to 7m19.199s
      
      [1] https://github.com/jthornber/device-mapper-test-suiteSigned-off-by: default avatarNikos Tsironis <ntsironis@arrikto.com>
      Signed-off-by: default avatarIlias Tsitsimpis <iliastsi@arrikto.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      e9566e99
    • Arnaldo Carvalho de Melo's avatar
      perf parse-events: Fix unchecked usage of strncpy() · 8691aa52
      Arnaldo Carvalho de Melo authored
      [ Upstream commit bd8d57fb ]
      
      The strncpy() function may leave the destination string buffer
      unterminated, better use strlcpy() that we have a __weak fallback
      implementation for systems without it.
      
      This fixes this warning on an Alpine Linux Edge system with gcc 8.2:
      
        util/parse-events.c: In function 'print_symbol_events':
        util/parse-events.c:2465:4: error: 'strncpy' specified bound 100 equals destination size [-Werror=stringop-truncation]
            strncpy(name, syms->symbol, MAX_NAME_LEN);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        In function 'print_symbol_events.constprop',
            inlined from 'print_events' at util/parse-events.c:2508:2:
        util/parse-events.c:2465:4: error: 'strncpy' specified bound 100 equals destination size [-Werror=stringop-truncation]
            strncpy(name, syms->symbol, MAX_NAME_LEN);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        In function 'print_symbol_events.constprop',
            inlined from 'print_events' at util/parse-events.c:2511:2:
        util/parse-events.c:2465:4: error: 'strncpy' specified bound 100 equals destination size [-Werror=stringop-truncation]
            strncpy(name, syms->symbol, MAX_NAME_LEN);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        cc1: all warnings being treated as errors
      
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Fixes: 947b4ad1 ("perf list: Fix max event string size")
      Link: https://lkml.kernel.org/n/tip-b663e33bm6x8hrkie4uxh7u2@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      8691aa52
    • Arnaldo Carvalho de Melo's avatar
      perf svghelper: Fix unchecked usage of strncpy() · f9e281df
      Arnaldo Carvalho de Melo authored
      [ Upstream commit 2f530253 ]
      
      The strncpy() function may leave the destination string buffer
      unterminated, better use strlcpy() that we have a __weak fallback
      implementation for systems without it.
      
      In this specific case this would only happen if fgets() was buggy, as
      its man page states that it should read one less byte than the size of
      the destination buffer, so that it can put the nul byte at the end of
      it, so it would never copy 255 non-nul chars, as fgets reads into the
      orig buffer at most 254 non-nul chars and terminates it. But lets just
      switch to strlcpy to keep the original intent and silence the gcc 8.2
      warning.
      
      This fixes this warning on an Alpine Linux Edge system with gcc 8.2:
      
        In function 'cpu_model',
            inlined from 'svg_cpu_box' at util/svghelper.c:378:2:
        util/svghelper.c:337:5: error: 'strncpy' output may be truncated copying 255 bytes from a string of length 255 [-Werror=stringop-truncation]
             strncpy(cpu_m, &buf[13], 255);
             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Arjan van de Ven <arjan@linux.intel.com>
      Fixes: f48d55ce ("perf: Add a SVG helper library file")
      Link: https://lkml.kernel.org/n/tip-xzkoo0gyr56gej39ltivuh9g@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      f9e281df
    • Adrian Hunter's avatar
      perf intel-pt: Fix error with config term "pt=0" · 9da7dfdb
      Adrian Hunter authored
      [ Upstream commit 1c6f709b ]
      
      Users should never use 'pt=0', but if they do it may give a meaningless
      error:
      
      	$ perf record -e intel_pt/pt=0/u uname
      	Error:
      	The sys_perf_event_open() syscall returned with 22 (Invalid argument) for
      	event (intel_pt/pt=0/u).
      
      Fix that by forcing 'pt=1'.
      
      Committer testing:
      
        # perf record -e intel_pt/pt=0/u uname
        Error:
        The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (intel_pt/pt=0/u).
        /bin/dmesg | grep -i perf may provide additional information.
      
        # perf record -e intel_pt/pt=0/u uname
        pt=0 doesn't make sense, forcing pt=1
        Linux
        [ perf record: Woken up 1 times to write data ]
        [ perf record: Captured and wrote 0.020 MB perf.data ]
        #
      Signed-off-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
      Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Link: http://lkml.kernel.org/r/b7c5b4e5-9497-10e5-fd43-5f3e4a0fe51d@intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      9da7dfdb
    • Sergey Senozhatsky's avatar
      tty/serial: do not free trasnmit buffer page under port lock · 80c8e528
      Sergey Senozhatsky authored
      [ Upstream commit d7240214 ]
      
      LKP has hit yet another circular locking dependency between uart
      console drivers and debugobjects [1]:
      
           CPU0                                    CPU1
      
                                                  rhltable_init()
                                                   __init_work()
                                                    debug_object_init
           uart_shutdown()                          /* db->lock */
            /* uart_port->lock */                    debug_print_object()
             free_page()                              printk()
                                                       call_console_drivers()
              debug_check_no_obj_freed()                /* uart_port->lock */
               /* db->lock */
                debug_print_object()
      
      So there are two dependency chains:
      	uart_port->lock -> db->lock
      And
      	db->lock -> uart_port->lock
      
      This particular circular locking dependency can be addressed in several
      ways:
      
      a) One way would be to move debug_print_object() out of db->lock scope
         and, thus, break the db->lock -> uart_port->lock chain.
      b) Another one would be to free() transmit buffer page out of db->lock
         in UART code; which is what this patch does.
      
      It makes sense to apply a) and b) independently: there are too many things
      going on behind free(), none of which depend on uart_port->lock.
      
      The patch fixes transmit buffer page free() in uart_shutdown() and,
      additionally, in uart_port_startup() (as was suggested by Dmitry Safonov).
      
      [1] https://lore.kernel.org/lkml/20181211091154.GL23332@shao2-debian/T/#uSigned-off-by: default avatarSergey Senozhatsky <sergey.senozhatsky@gmail.com>
      Reviewed-by: default avatarPetr Mladek <pmladek@suse.com>
      Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Jiri Slaby <jslaby@suse.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Waiman Long <longman@redhat.com>
      Cc: Dmitry Safonov <dima@arista.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
      80c8e528