1. 02 May, 2013 8 commits
  2. 26 Apr, 2013 1 commit
  3. 25 Apr, 2013 4 commits
  4. 24 Apr, 2013 8 commits
    • Nicolas Pitre's avatar
      ARM: mcpm: provide an interface to set the SMP ops at run time · a7eb7c6f
      Nicolas Pitre authored
      This is cleaner than exporting the mcpm_smp_ops structure.
      Signed-off-by: default avatarNicolas Pitre <nico@linaro.org>
      Acked-by: default avatarJon Medhurst <tixy@linaro.org>
      a7eb7c6f
    • Nicolas Pitre's avatar
      ARM: mcpm: generic SMP secondary bringup and hotplug support · 9ff221ba
      Nicolas Pitre authored
      Now that the cluster power API is in place, we can use it for SMP secondary
      bringup and CPU hotplug in a generic fashion.
      Signed-off-by: default avatarNicolas Pitre <nico@linaro.org>
      Reviewed-by: default avatarSantosh Shilimkar <santosh.shilimkar@ti.com>
      Reviewed-by: default avatarWill Deacon <will.deacon@arm.com>
      9ff221ba
    • Dave Martin's avatar
      ARM: mcpm_head.S: vlock-based first man election · 1ae98561
      Dave Martin authored
      Instead of requiring the first man to be elected in advance (which
      can be suboptimal in some situations), this patch uses a per-
      cluster mutex to co-ordinate selection of the first man.
      
      This should also make it more feasible to reuse this code path for
      asynchronous cluster resume (as in CPUidle scenarios).
      
      We must ensure that the vlock data doesn't share a cacheline with
      anything else, or dirty cache eviction could corrupt it.
      Signed-off-by: default avatarDave Martin <dave.martin@linaro.org>
      Signed-off-by: default avatarNicolas Pitre <nicolas.pitre@linaro.org>
      Reviewed-by: default avatarSantosh Shilimkar <santosh.shilimkar@ti.com>
      Reviewed-by: default avatarWill Deacon <will.deacon@arm.com>
      1ae98561
    • Dave Martin's avatar
      ARM: mcpm: Add baremetal voting mutexes · 9762f12d
      Dave Martin authored
      This patch adds a simple low-level voting mutex implementation
      to be used to arbitrate during first man selection when no load/store
      exclusive instructions are usable.
      
      For want of a better name, these are called "vlocks".  (I was
      tempted to call them ballot locks, but "block" is way too confusing
      an abbreviation...)
      
      There is no function to wait for the lock to be released, and no
      vlock_lock() function since we don't need these at the moment.
      These could straightforwardly be added if vlocks get used for other
      purposes.
      
      For architectural correctness even Strongly-Ordered memory accesses
      require barriers in order to guarantee that multiple CPUs have a
      coherent view of the ordering of memory accesses.  Whether or not
      this matters depends on hardware implementation details of the
      memory system.  Since the purpose of this code is to provide a clean,
      generic locking mechanism with no platform-specific dependencies the
      barriers should be present to avoid unpleasant surprises on future
      platforms.
      
      Note:
      
        * When taking the lock, we don't care about implicit background
          memory operations and other signalling which may be pending,
          because those are not part of the critical section anyway.
      
          A DMB is sufficient to ensure correctly observed ordering if
          the explicit memory accesses in vlock_trylock.
      
        * No barrier is required after checking the election result,
          because the result is determined by the store to
          VLOCK_OWNER_OFFSET and is already globally observed due to the
          barriers in voting_end.  This means that global agreement on
          the winner is guaranteed, even before the winner is known
          locally.
      Signed-off-by: default avatarDave Martin <dave.martin@linaro.org>
      Signed-off-by: default avatarNicolas Pitre <nicolas.pitre@linaro.org>
      Reviewed-by: default avatarSantosh Shilimkar <santosh.shilimkar@ti.com>
      Reviewed-by: default avatarWill Deacon <will.deacon@arm.com>
      9762f12d
    • Dave Martin's avatar
      ARM: mcpm: introduce helpers for platform coherency exit/setup · 7fe31d28
      Dave Martin authored
      This provides helper methods to coordinate between CPUs coming down
      and CPUs going up, as well as documentation on the used algorithms,
      so that cluster teardown and setup
      operations are not done for a cluster simultaneously.
      
      For use in the power_down() implementation:
        * __mcpm_cpu_going_down(unsigned int cluster, unsigned int cpu)
        * __mcpm_outbound_enter_critical(unsigned int cluster)
        * __mcpm_outbound_leave_critical(unsigned int cluster)
        * __mcpm_cpu_down(unsigned int cluster, unsigned int cpu)
      
      The power_up_setup() helper should do platform-specific setup in
      preparation for turning the CPU on, such as invalidating local caches
      or entering coherency.  It must be assembler for now, since it must
      run before the MMU can be switched on.  It is passed the affinity level
      for which initialization should be performed.
      
      Because the mcpm_sync_struct content is looked-up and modified
      with the cache enabled or disabled depending on the code path, it is
      crucial to always ensure proper cache maintenance to update main memory
      right away.  The sync_cache_*() helpers are used to that end.
      
      Also, in order to prevent a cached writer from interfering with an
      adjacent non-cached writer, we ensure each state variable is located to
      a separate cache line.
      
      Thanks to Nicolas Pitre and Achin Gupta for the help with this
      patch.
      Signed-off-by: default avatarDave Martin <dave.martin@linaro.org>
      Signed-off-by: default avatarNicolas Pitre <nico@linaro.org>
      Reviewed-by: default avatarWill Deacon <will.deacon@arm.com>
      7fe31d28
    • Nicolas Pitre's avatar
      ARM: mcpm: introduce the CPU/cluster power API · 7c2b8605
      Nicolas Pitre authored
      This is the basic API used to handle the powering up/down of individual
      CPUs in a (multi-)cluster system.  The platform specific backend
      implementation has the responsibility to also handle the cluster level
      power as well when the first/last CPU in a cluster is brought up/down.
      Signed-off-by: default avatarNicolas Pitre <nico@linaro.org>
      Reviewed-by: default avatarSantosh Shilimkar <santosh.shilimkar@ti.com>
      Reviewed-by: default avatarWill Deacon <will.deacon@arm.com>
      7c2b8605
    • Nicolas Pitre's avatar
      ARM: multi-cluster PM: secondary kernel entry code · e8db288e
      Nicolas Pitre authored
      CPUs in cluster based systems, such as big.LITTLE, have special needs
      when entering the kernel due to a hotplug event, or when resuming from
      a deep sleep mode.
      
      This is vectorized so multiple CPUs can enter the kernel in parallel
      without serialization.
      
      The mcpm prefix stands for "multi cluster power management", however
      this is usable on single cluster systems as well.  Only the basic
      structure is introduced here.  This will be extended with later patches.
      
      In order not to complexify things more than they currently have to,
      the planned work to make runtime adjusted MPIDR based indexing and
      dynamic memory allocation for cluster states is postponed to a later
      cycle. The MAX_NR_CLUSTERS and MAX_CPUS_PER_CLUSTER static definitions
      should be sufficient for those systems expected to be available in the
      near future.
      Signed-off-by: default avatarNicolas Pitre <nico@linaro.org>
      Reviewed-by: default avatarSantosh Shilimkar <santosh.shilimkar@ti.com>
      Reviewed-by: default avatarWill Deacon <will.deacon@arm.com>
      e8db288e
    • Nicolas Pitre's avatar
      ARM: cacheflush: add synchronization helpers for mixed cache state accesses · 0c91e7e0
      Nicolas Pitre authored
      Algorithms used by the MCPM layer rely on state variables which are
      accessed while the cache is either active or inactive, depending
      on the code path and the active state.
      
      This patch introduces generic cache maintenance helpers to provide the
      necessary cache synchronization for such state variables to always hit
      main memory in an ordered way.
      Signed-off-by: default avatarNicolas Pitre <nico@linaro.org>
      Acked-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
      Acked-by: default avatarDave Martin <dave.martin@linaro.org>
      0c91e7e0
  5. 21 Apr, 2013 8 commits
    • Linus Torvalds's avatar
      Linux 3.9-rc8 · 60d509fa
      Linus Torvalds authored
      60d509fa
    • Linus Torvalds's avatar
      Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 31259294
      Linus Torvalds authored
      Pull perf fixes from Ingo Molnar:
       "Misc fixes"
      
      * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        perf/x86: Fix offcore_rsp valid mask for SNB/IVB
        perf: Treat attr.config as u64 in perf_swevent_init()
      31259294
    • Linus Torvalds's avatar
      Merge branch 'vm_ioremap_memory-examples' · 12c71c4b
      Linus Torvalds authored
      I'm going to do an -rc8, so I'm just going to do this rather than delay
      it any further. They are arguably stable material anyway.
      
      * vm_ioremap_memory-examples:
        mtdchar: remove no-longer-used vma helpers
        vm: convert snd_pcm_lib_mmap_iomem() to vm_iomap_memory() helper
        vm: convert fb_mmap to vm_iomap_memory() helper
        vm: convert mtdchar mmap to vm_iomap_memory() helper
        vm: convert HPET mmap to vm_iomap_memory() helper
      12c71c4b
    • Linus Torvalds's avatar
      Merge branch 'x86-kdump-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 830ac852
      Linus Torvalds authored
      Pull kdump fixes from Peter Anvin:
       "The kexec/kdump people have found several problems with the support
        for loading over 4 GiB that was introduced in this merge cycle.  This
        is partly due to a number of design problems inherent in the way the
        various pieces of kdump fit together (it is pretty horrifically manual
        in many places.)
      
        After a *lot* of iterations this is the patchset that was agreed upon,
        but of course it is now very late in the cycle.  However, because it
        changes both the syntax and semantics of the crashkernel option, it
        would be desirable to avoid a stable release with the broken
        interfaces."
      
      I'm not happy with the timing, since originally the plan was to release
      the final 3.9 tomorrow.  But apparently I'm doing an -rc8 instead...
      
      * 'x86-kdump-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        kexec: use Crash kernel for Crash kernel low
        x86, kdump: Change crashkernel_high/low= to crashkernel=,high/low
        x86, kdump: Retore crashkernel= to allocate under 896M
        x86, kdump: Set crashkernel_low automatically
      830ac852
    • Linus Torvalds's avatar
      Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · db93f8b4
      Linus Torvalds authored
      Pull x86 fixes from Peter Anvin:
       "Three groups of fixes:
      
         1. Make sure we don't execute the early microcode patching if family
            < 6, since it would touch MSRs which don't exist on those
            families, causing crashes.
      
         2. The Xen partial emulation of HyperV can be dealt with more
            gracefully than just disabling the driver.
      
         3. More EFI variable space magic.  In particular, variables hidden
            from runtime code need to be taken into account too."
      
      * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        x86, microcode: Verify the family before dispatching microcode patching
        x86, hyperv: Handle Xen emulation of Hyper-V more gracefully
        x86,efi: Implement efi_no_storage_paranoia parameter
        efi: Export efi_query_variable_store() for efivars.ko
        x86/Kconfig: Make EFI select UCS2_STRING
        efi: Distinguish between "remaining space" and actually used space
        efi: Pass boot services variable info to runtime code
        Move utf16 functions to kernel core and rename
        x86,efi: Check max_size only if it is non-zero.
        x86, efivars: firmware bug workarounds should be in platform code
      db93f8b4
    • Linus Torvalds's avatar
      Merge branch 'fixes' of git://git.linaro.org/people/rmk/linux-arm · 8c3a13c8
      Linus Torvalds authored
      Pull ARM fixes from Russell King:
       "A set of fixes from various people - Will Deacon gets a prize for
        removing code this time around.  The biggest fix in this lot is
        sorting out the ARM740T mess.  The rest are relatively small fixes."
      
      * 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
        ARM: 7699/1: sched_clock: Add more notrace to prevent recursion
        ARM: 7698/1: perf: fix group validation when using enable_on_exec
        ARM: 7697/1: hw_breakpoint: do not use __cpuinitdata for dbg_cpu_pm_nb
        ARM: 7696/1: Fix kexec by setting outer_cache.inv_all for Feroceon
        ARM: 7694/1: ARM, TCM: initialize TCM in paging_init(), instead of setup_arch()
        ARM: 7692/1: iop3xx: move IOP3XX_PERIPHERAL_VIRT_BASE
        ARM: modules: don't export cpu_set_pte_ext when !MMU
        ARM: mm: remove broken condition check for v4 flushing
        ARM: mm: fix numerous hideous errors in proc-arm740.S
        ARM: cache: remove ARMv3 support code
        ARM: tlbflush: remove ARMv3 support
      8c3a13c8
    • Linus Torvalds's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc · 851b3f32
      Linus Torvalds authored
      Pull sparc fixes from David Miller:
      
       1) Fix race in sparc64 TLB shootdowns, we have to synchronize with the
          sibling cpus completing if we are passing them a reference via
          pointer to a data structure.
      
       2) Fix cleaning of bitmaps in sparc32, from Akinobu Mita.
      
       3) Fix various sparc header mistakes, some of which resulted in
          userland build breakage.  From Sam Ravnborg.
      
       4) Kill ghost declarations and defines missed when several bits of code
          got deleted recently.
      
      * git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
        sparc64: Fix race in TLB batch processing.
        sparc: use asm-generic version of types.h
        bbc_i2c: fix section mismatch warning
        sparc: use generic headers
        sparc:cleanup unused code in smp_32.h
        sparc/iommu: fix typo s/265KB/256KB/
        sparc/srmmu: clear trailing edge of bitmap properly
        sparc:remove unused declaration smp_boot_cpus()
      851b3f32
    • Linus Torvalds's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net · c437d888
      Linus Torvalds authored
      Pull networking updates from David Miller:
      
       1) ax88796 does 64-bit divides which causes link errors on ARM, fix
          from Arnd Bergmann.
      
       2) Once an improper offload setting is detected on an SKB we don't rate
          limit the log message so we can very easily live lock.  From Ben
          Greear.
      
       3) Openvswitch cannot report vport configuration changes reliably
          because it didn't preallocate the netlink notification message
          before changing state.  From Jesse Gross.
      
       4) The effective UID/GID SCM credentials fix, from Linus.
      
       5) When a user explicitly asks for wireless authentication, cfg80211
          isn't told about the AP detachment leaving inconsistent state.  Fix
          from Johannes Berg.
      
       6) Fix self-MAC checks in batman-adv on multi-mesh nodes, from Antonio
          Quartulli.
      
       7) Revert build_skb() change sin IGB driver, can result in memory
          corruption.  From Alexander Duyck.
      
       8) Fix setting VLANs on virtual functions in IXGBE, from Greg Rose.
      
       9) Fix TSO races in qlcnic driver, from Sritej Velaga.
      
      10) In bnx2x the kernel driver and UNDI firmware can try to program the
          chip at the same time, resulting in corruption.  Add proper
          synchronization.  From Dmitry Kravkov.
      
      11) Fix corruption of status block in firmware ram in bxn2x, from Ariel
          Elior.
      
      12) Fix load balancing hash regression of bonding driver in forwarding
          configurations, from Eric Dumazet.
      
      13) Fix TS ECR regression in TCP by calling tcp_replace_ts_recent() in
          all the right spots, from Eric Dumazet.
      
      14) Fix several bonding bugs having to do with address manintainence,
          including not removing address when configuration operations
          encounter errors, missed locking on the address lists, missing
          refcounting on VLAN objects, etc.  All from Nikolay Aleksandrov.
      
      15) Add workarounds for firmware bugs in LTE qmi_wwan devices, wherein
          the devices fail to add a proper ethernet header while on LTE
          networks but otherwise properly do so on 2G and 3G ones.  From Bjørn
          Mork.
      
      * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (38 commits)
        net: fix incorrect credentials passing
        net: rate-limit warn-bad-offload splats.
        net: ax88796: avoid 64 bit arithmetic
        qlge: Update version to 1.00.00.32.
        qlge: Fix ethtool autoneg advertising.
        qlge: Fix receive path to drop error frames
        net: qmi_wwan: prevent duplicate mac address on link (firmware bug workaround)
        net: qmi_wwan: fixup destination address (firmware bug workaround)
        net: qmi_wwan: fixup missing ethernet header (firmware bug workaround)
        bonding: in bond_mc_swap() bond's mc addr list is walked without lock
        bonding: disable netpoll on enslave failure
        bonding: primary_slave & curr_active_slave are not cleaned on enslave failure
        bonding: vlans don't get deleted on enslave failure
        bonding: mc addresses don't get deleted on enslave failure
        pkt_sched: fix error return code in fw_change_attrs()
        irda: small read past the end of array in debug code
        tcp: call tcp_replace_ts_recent() from tcp_ack()
        netfilter: xt_rpfilter: skip locally generated broadcast/multicast, too
        netfilter: ipset: bitmap:ip,mac: fix listing with timeout
        bonding: fix l23 and l34 load balancing in forwarding path
        ...
      c437d888
  6. 20 Apr, 2013 2 commits
  7. 19 Apr, 2013 9 commits
    • H. Peter Anvin's avatar
      x86, microcode: Verify the family before dispatching microcode patching · 74c3e3fc
      H. Peter Anvin authored
      For each CPU vendor that implements CPU microcode patching, there will
      be a minimum family for which this is implemented.  Verify this
      minimum level of support.
      
      This can be done in the dispatch function or early in the application
      functions.  Doing the latter turned out to be somewhat awkward because
      of the ineviable split between the BSP and the AP paths, and rather
      than pushing deep into the application functions, do this in
      the dispatch function.
      Reported-by: default avatar"Bryan O'Donoghue" <bryan.odonoghue.lkml@nexus-software.ie>
      Suggested-by: default avatarBorislav Petkov <bp@alien8.de>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Link: http://lkml.kernel.org/r/1366392183-4149-1-git-send-email-bryan.odonoghue.lkml@nexus-software.ie
      74c3e3fc
    • Ben Greear's avatar
      net: rate-limit warn-bad-offload splats. · c846ad9b
      Ben Greear authored
      If one does do something unfortunate and allow a
      bad offload bug into the kernel, this the
      skb_warn_bad_offload can effectively live-lock the
      system, filling the logs with the same error over
      and over.
      
      Add rate limitation to this so that box remains otherwise
      functional in this case.
      Signed-off-by: default avatarBen Greear <greearb@candelatech.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      c846ad9b
    • Arnd Bergmann's avatar
      net: ax88796: avoid 64 bit arithmetic · b261c20f
      Arnd Bergmann authored
      When building ax88796 on an ARM platform with 64-bit resource_size_t,
      we currently get
      
      drivers/net/ethernet/8390/ax88796.c:875: undefined reference to `__aeabi_uldivmod'
      
      because we do a division on the length of the MMIO resource.
      Since we know that this resource is very short, using an
      "unsigned long" instead of "resource_size_t" is entirely
      sufficient, and avoids this link-time error.
      
      Cc: Ben Dooks <ben-linux@fluff.org>
      Cc: netdev@vger.kernel.org
      Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b261c20f
    • Jitendra Kalsaria's avatar
    • Jitendra Kalsaria's avatar
      qlge: Fix ethtool autoneg advertising. · c5e991af
      Jitendra Kalsaria authored
      Autoneg is supported on specific port types only. Fix the driver to advertise
      autoneg based on the port type.
      Signed-off-by: default avatarJitendra Kalsaria <jitendra.kalsaria@qlogic.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      c5e991af
    • Sritej Velaga's avatar
      qlge: Fix receive path to drop error frames · ae721f3a
      Sritej Velaga authored
      o Fix the driver to drop error frames in the receive path
      o Update error counter which was not getting incremented
      Signed-off-by: default avatarSritej Velaga <sritej.velaga@qlogic.com>
      Signed-off-by: default avatarJitendra Kalsaria <jitendra.kalsaria@qlogic.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      ae721f3a
    • David S. Miller's avatar
      Merge branch 'qmi_wwan' · b79d4a8d
      David S. Miller authored
      Bjørn Mork says:
      
      ====================
      This series adds workarounds for 3 different firmware bugs, each
      preventing the affected devices from working at all. I therefore
      humbly request that these fixes go to stable-3.8 (if still
      maintained) and 3.9 (either via net if still possible, or via
      stable if not).
      
      All 3 workarounds are applied to all devices supported by the driver.
      Adding quirks for specific devices was considered as an alternative,
      but was rejected because we have too little information about the
      exact distribution of the buggy firmwares. All we know is that the
      same bug shows up in devices from at least 3 different, and presumably
      independent, vendors.
      
      The workarounds have instead been designed to automatically apply
      when necessary, and to have as little impact as possible on unaffected
      devices.  The series has been tested on a number of devices both with
      and without these bugs.
      
      The series should apply cleanly to net/master, net-next/master and
      stable/linux-3.8.y
      ====================
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b79d4a8d
    • Bjørn Mork's avatar
      net: qmi_wwan: prevent duplicate mac address on link (firmware bug workaround) · cc6ba5fd
      Bjørn Mork authored
      We normally trust and use the CDC functional descriptors provided by a
      number of devices.  But some of these will erroneously list the address
      reserved for the device end of the link.  Attempting to use this on
      both the device and host side will naturally not work.
      
      Work around this bug by ignoring the functional descriptor and assign a
      random address instead in this case.
      Signed-off-by: default avatarBjørn Mork <bjorn@mork.no>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      cc6ba5fd
    • Bjørn Mork's avatar
      net: qmi_wwan: fixup destination address (firmware bug workaround) · 6483bdc9
      Bjørn Mork authored
      Received packets are sometimes addressed to 00:a0:c6:00:00:00
      instead of the address the device firmware should have learned
      from the host:
      
      321.224126 77.16.85.204 -> 148.122.171.134 ICMP 98 Echo (ping) request  id=0x4025, seq=64/16384, ttl=64
      
      0000  82 c0 82 c9 f1 67 82 c0 82 c9 f1 67 08 00 45 00   .....g.....g..E.
      0010  00 54 00 00 40 00 40 01 57 cc 4d 10 55 cc 94 7a   .T..@.@.W.M.U..z
      0020  ab 86 08 00 62 fc 40 25 00 40 b2 bc 6e 51 00 00   ....b.@%.@..nQ..
      0030  00 00 6b bd 09 00 00 00 00 00 10 11 12 13 14 15   ..k.............
      0040  16 17 18 19 1a 1b 1c 1d 1e 1f 20 21 22 23 24 25   .......... !"#$%
      0050  26 27 28 29 2a 2b 2c 2d 2e 2f 30 31 32 33 34 35   &'()*+,-./012345
      0060  36 37                                             67
      
      321.240607 148.122.171.134 -> 77.16.85.204 ICMP 98 Echo (ping) reply    id=0x4025, seq=64/16384, ttl=55
      
      0000  00 a0 c6 00 00 00 02 50 f3 00 00 00 08 00 45 00   .......P......E.
      0010  00 54 00 56 00 00 37 01 a0 76 94 7a ab 86 4d 10   .T.V..7..v.z..M.
      0020  55 cc 00 00 6a fc 40 25 00 40 b2 bc 6e 51 00 00   U...j.@%.@..nQ..
      0030  00 00 6b bd 09 00 00 00 00 00 10 11 12 13 14 15   ..k.............
      0040  16 17 18 19 1a 1b 1c 1d 1e 1f 20 21 22 23 24 25   .......... !"#$%
      0050  26 27 28 29 2a 2b 2c 2d 2e 2f 30 31 32 33 34 35   &'()*+,-./012345
      0060  36 37                                             67
      
      The bogus address is always the same, and matches the address
      suggested by many devices as a default address.  It is likely a
      hardcoded firmware default.
      
      The circumstances where this bug has been observed indicates that
      the trigger is related to timing or some other factor the host
      cannot control. Repeating the exact same configuration sequence
      that caused it to trigger once, will not necessarily cause it to
      trigger the next time. Reproducing the bug is therefore difficult.
      This opens up a possibility that the bug is more common than we can
      confirm, because affected devices often will work properly again
      after a reset.  A procedure most users are likely to try out before
      reporting a bug.
      
      Unconditionally rewriting the destination address if the first digit
      of the received packet is 0, is considered an acceptable compromise
      since we already have to inspect this digit.  The simplification will
      cause unnecessary rewrites if the real address starts with 0, but this
      is still better than adding additional tests for this particular case.
      Signed-off-by: default avatarBjørn Mork <bjorn@mork.no>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      6483bdc9