Skip to content
  1. Jun 12, 2012
  2. Jun 09, 2012
  3. Jun 07, 2012
  4. Jun 06, 2012
  5. Jun 05, 2012
    • Vinicius Costa Gomes's avatar
      Bluetooth: Fix checking the wrong flag when accepting a socket · ddcd0f41
      Vinicius Costa Gomes authored
      
      
      Most probably a typo, the check should have been for BT_SK_DEFER_SETUP
      instead of BT_DEFER_SETUP (which right now only represents a socket
      option).
      
      Signed-off-by: default avatarVinicius Costa Gomes <vinicius.gomes@openbossa.org>
      Acked-by: default avatarAndrei Emeltchenko <andrei.emeltchenko@intel.com>
      Signed-off-by: default avatarGustavo Padovan <gustavo.padovan@collabora.co.uk>
      ddcd0f41
    • Johannes Berg's avatar
      iwlwifi: disable WoWLAN if !CONFIG_PM_SLEEP · fcb6ff5e
      Johannes Berg authored
      
      
      If CONFIG_PM_SLEEP is disabled, then iwlwifi doesn't
      support suspend/resume handlers and thus mac80211
      (correctly) refuses advertising WoWLAN. Disable
      WoWLAN in the driver in this case.
      
      Cc: stable@kernel.org
      Reported-by: default avatarSebastian Kemper <sebastian_ml@gmx.net>
      Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      fcb6ff5e
    • Arik Nemtsov's avatar
      mac80211: fix non RCU-safe sta_list manipulation · 794454ce
      Arik Nemtsov authored
      
      
      sta_info_cleanup locks the sta_list using rcu_read_lock however
      the delete operation isn't rcu safe. A race between sta_info_cleanup
      timer being called and a STA being removed can occur which leads
      to a panic while traversing sta_list. Fix this by switching to the
      RCU-safe versions.
      
      Cc: stable@vger.kernel.org
      Reported-by: default avatarEyal Shapira <eyal@wizery.com>
      Signed-off-by: default avatarArik Nemtsov <arik@wizery.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      794454ce
    • Seth Forshee's avatar
      bcma: add ext PA workaround for BCM4331 and BCM43431 · 69aaedd3
      Seth Forshee authored
      
      
      MacBook Pro models with BCM4331 wireless have been found to have the ext
      PA lines disabled after resuming from S3 without external power attach.
      This causes them to be unable to transmit. Add a workaround to ensure
      that the ext PA lines are enabled on BCM4331. Also extend all handling
      of ext PA line muxing to BCM43431 as is done in the Broadcom SDK.
      
      BugLink: http://bugs.launchpad.net/bugs/925577
      Cc: Arend van Spriel <arend@broadcom.com>
      Cc: Hauke Mehrtens <hauke@hauke-m.de>
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarSeth Forshee <seth.forshee@canonical.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      69aaedd3
    • Stanislaw Gruszka's avatar
      rt2x00: use atomic variable for seqno · e5851dac
      Stanislaw Gruszka authored
      
      
      Remove spinlock as atomic_t can be used instead. Note we use only 16
      lower bits, upper bits are changed but we impilcilty cast to u16.
      
      This fix possible deadlock on IBSS mode reproted by lockdep:
      
      =================================
      [ INFO: inconsistent lock state ]
      3.4.0-wl+ #4 Not tainted
      ---------------------------------
      inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
      kworker/u:2/30374 [HC0[0]:SC0[0]:HE1:SE1] takes:
       (&(&intf->seqlock)->rlock){+.?...}, at: [<f9979a20>] rt2x00queue_create_tx_descriptor+0x380/0x490 [rt2x00lib]
      {IN-SOFTIRQ-W} state was registered at:
        [<c04978ab>] __lock_acquire+0x47b/0x1050
        [<c0498504>] lock_acquire+0x84/0xf0
        [<c0835733>] _raw_spin_lock+0x33/0x40
        [<f9979a20>] rt2x00queue_create_tx_descriptor+0x380/0x490 [rt2x00lib]
        [<f9979f2a>] rt2x00queue_write_tx_frame+0x1a/0x300 [rt2x00lib]
        [<f997834f>] rt2x00mac_tx+0x7f/0x380 [rt2x00lib]
        [<f98fe363>] __ieee80211_tx+0x1b3/0x300 [mac80211]
        [<f98ffdf5>] ieee80211_tx+0x105/0x130 [mac80211]
        [<f99000dd>] ieee80211_xmit+0xad/0x100 [mac80211]
        [<f9900519>] ieee80211_subif_start_xmit+0x2d9/0x930 [mac80211]
        [<c0782e87>] dev_hard_start_xmit+0x307/0x660
        [<c079bb71>] sch_direct_xmit+0xa1/0x1e0
        [<c0784bb3>] dev_queue_xmit+0x183/0x730
        [<c078c27a>] neigh_resolve_output+0xfa/0x1e0
        [<c07b436a>] ip_finish_output+0x24a/0x460
        [<c07b4897>] ip_output+0xb7/0x100
        [<c07b2d60>] ip_local_out+0x20/0x60
        [<c07e01ff>] igmpv3_sendpack+0x4f/0x60
        [<c07e108f>] igmp_ifc_timer_expire+0x29f/0x330
        [<c04520fc>] run_timer_softirq+0x15c/0x2f0
        [<c0449e3e>] __do_softirq+0xae/0x1e0
      irq event stamp: 18380437
      hardirqs last  enabled at (18380437): [<c0526027>] __slab_alloc.clone.3+0x67/0x5f0
      hardirqs last disabled at (18380436): [<c0525ff3>] __slab_alloc.clone.3+0x33/0x5f0
      softirqs last  enabled at (18377616): [<c0449eb3>] __do_softirq+0x123/0x1e0
      softirqs last disabled at (18377611): [<c041278d>] do_softirq+0x9d/0xe0
      
      other info that might help us debug this:
       Possible unsafe locking scenario:
      
             CPU0
             ----
        lock(&(&intf->seqlock)->rlock);
        <Interrupt>
          lock(&(&intf->seqlock)->rlock);
      
       *** DEADLOCK ***
      
      4 locks held by kworker/u:2/30374:
       #0:  (wiphy_name(local->hw.wiphy)){++++.+}, at: [<c045cf99>] process_one_work+0x109/0x3f0
       #1:  ((&sdata->work)){+.+.+.}, at: [<c045cf99>] process_one_work+0x109/0x3f0
       #2:  (&ifibss->mtx){+.+.+.}, at: [<f98f005b>] ieee80211_ibss_work+0x1b/0x470 [mac80211]
       #3:  (&intf->beacon_skb_mutex){+.+...}, at: [<f997a644>] rt2x00queue_update_beacon+0x24/0x50 [rt2x00lib]
      
      stack backtrace:
      Pid: 30374, comm: kworker/u:2 Not tainted 3.4.0-wl+ #4
      Call Trace:
       [<c04962a6>] print_usage_bug+0x1f6/0x220
       [<c0496a12>] mark_lock+0x2c2/0x300
       [<c0495ff0>] ? check_usage_forwards+0xc0/0xc0
       [<c04978ec>] __lock_acquire+0x4bc/0x1050
       [<c0527890>] ? __kmalloc_track_caller+0x1c0/0x1d0
       [<c0777fb6>] ? copy_skb_header+0x26/0x90
       [<c0498504>] lock_acquire+0x84/0xf0
       [<f9979a20>] ? rt2x00queue_create_tx_descriptor+0x380/0x490 [rt2x00lib]
       [<c0835733>] _raw_spin_lock+0x33/0x40
       [<f9979a20>] ? rt2x00queue_create_tx_descriptor+0x380/0x490 [rt2x00lib]
       [<f9979a20>] rt2x00queue_create_tx_descriptor+0x380/0x490 [rt2x00lib]
       [<f997a5cf>] rt2x00queue_update_beacon_locked+0x5f/0xb0 [rt2x00lib]
       [<f997a64d>] rt2x00queue_update_beacon+0x2d/0x50 [rt2x00lib]
       [<f9977e3a>] rt2x00mac_bss_info_changed+0x1ca/0x200 [rt2x00lib]
       [<f9977c70>] ? rt2x00mac_remove_interface+0x70/0x70 [rt2x00lib]
       [<f98e4dd0>] ieee80211_bss_info_change_notify+0xe0/0x1d0 [mac80211]
       [<f98ef7b8>] __ieee80211_sta_join_ibss+0x3b8/0x610 [mac80211]
       [<c0496ab4>] ? mark_held_locks+0x64/0xc0
       [<c0440012>] ? virt_efi_query_capsule_caps+0x12/0x50
       [<f98efb09>] ieee80211_sta_join_ibss+0xf9/0x140 [mac80211]
       [<f98f0456>] ieee80211_ibss_work+0x416/0x470 [mac80211]
       [<c0496d8b>] ? trace_hardirqs_on+0xb/0x10
       [<c077683b>] ? skb_dequeue+0x4b/0x70
       [<f98f207f>] ieee80211_iface_work+0x13f/0x230 [mac80211]
       [<c045cf99>] ? process_one_work+0x109/0x3f0
       [<c045d015>] process_one_work+0x185/0x3f0
       [<c045cf99>] ? process_one_work+0x109/0x3f0
       [<f98f1f40>] ? ieee80211_teardown_sdata+0xa0/0xa0 [mac80211]
       [<c045ed86>] worker_thread+0x116/0x270
       [<c045ec70>] ? manage_workers+0x1e0/0x1e0
       [<c0462f64>] kthread+0x84/0x90
       [<c0462ee0>] ? __init_kthread_worker+0x60/0x60
       [<c083d382>] kernel_thread_helper+0x6/0x10
      
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarStanislaw Gruszka <sgruszka@redhat.com>
      Acked-by: default avatarHelmut Schaa <helmut.schaa@googlemail.com>
      Acked-by: default avatarGertjan van Wingerde <gwingerde@gmail.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      e5851dac
    • Joe Perches's avatar
      brcmfmac: Fix likely misuse of | for & · f304a993
      Joe Perches authored
      
      
      Using | with a constant is always true.
      Likely this should have be &.
      
      Signed-off-by: default avatarJoe Perches <joe@perches.com>
      Acked-by: default avatarArend van Spriel <arend@broadcom.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      f304a993
    • Joe Perches's avatar
      mac80211: Fix likely misuse of | for & · 5204267d
      Joe Perches authored
      
      
      Using | with a constant is always true.
      Likely this should have be &.
      
      cc: Ben Greear <greearb@candelatech.com>
      Signed-off-by: default avatarJoe Perches <joe@perches.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      5204267d
    • Felix Fietkau's avatar
      mac80211: add missing rcu_read_lock/unlock in agg-rx session timer · d8c7aae6
      Felix Fietkau authored
      
      
      Fixes a lockdep warning:
      
      ===================================================
      [ INFO: suspicious rcu_dereference_check() usage. ]
      ---------------------------------------------------
      net/mac80211/agg-rx.c:148 invoked rcu_dereference_check() without protection!
      
      other info that might help us debug this:
      
      rcu_scheduler_active = 1, debug_locks = 1
      1 lock held by arecord/11226:
       #0:  (&tid_agg_rx->session_timer){+.-...}, at: [<ffffffff81066bb0>] call_timer_fn+0x0/0x360
      
      stack backtrace:
      Pid: 11226, comm: arecord Not tainted 3.1.0-kml #16
      Call Trace:
       <IRQ>  [<ffffffff81093454>] lockdep_rcu_dereference+0xa4/0xc0
       [<ffffffffa02778c9>] sta_rx_agg_session_timer_expired+0xc9/0x110 [mac80211]
       [<ffffffffa0277800>] ? ieee80211_process_addba_resp+0x220/0x220 [mac80211]
       [<ffffffff81066c3a>] call_timer_fn+0x8a/0x360
       [<ffffffff81066bb0>] ? init_timer_deferrable_key+0x30/0x30
       [<ffffffff81477bb0>] ? _raw_spin_unlock_irq+0x30/0x70
       [<ffffffff81067049>] run_timer_softirq+0x139/0x310
       [<ffffffff81091d5e>] ? put_lock_stats.isra.25+0xe/0x40
       [<ffffffff810922ac>] ? lock_release_holdtime.part.26+0xdc/0x160
       [<ffffffffa0277800>] ? ieee80211_process_addba_resp+0x220/0x220 [mac80211]
       [<ffffffff8105cb78>] __do_softirq+0xc8/0x3c0
       [<ffffffff8108f088>] ? tick_dev_program_event+0x48/0x110
       [<ffffffff8108f16f>] ? tick_program_event+0x1f/0x30
       [<ffffffff81153b15>] ? putname+0x35/0x50
       [<ffffffff8147a43c>] call_softirq+0x1c/0x30
       [<ffffffff81004c55>] do_softirq+0xa5/0xe0
       [<ffffffff8105d1ee>] irq_exit+0xae/0xe0
       [<ffffffff8147ac6b>] smp_apic_timer_interrupt+0x6b/0x98
       [<ffffffff81479ab3>] apic_timer_interrupt+0x73/0x80
       <EOI>  [<ffffffff8146aac6>] ? free_debug_processing+0x1a1/0x1d5
       [<ffffffff81153b15>] ? putname+0x35/0x50
       [<ffffffff8146ab2b>] __slab_free+0x31/0x2ca
       [<ffffffff81477c3a>] ? _raw_spin_unlock_irqrestore+0x4a/0x90
       [<ffffffff81253b8f>] ? __debug_check_no_obj_freed+0x15f/0x210
       [<ffffffff81097054>] ? lock_release_nested+0x84/0xc0
       [<ffffffff8113ec55>] ? kmem_cache_free+0x105/0x250
       [<ffffffff81153b15>] ? putname+0x35/0x50
       [<ffffffff81153b15>] ? putname+0x35/0x50
       [<ffffffff8113ed8f>] kmem_cache_free+0x23f/0x250
       [<ffffffff81153b15>] putname+0x35/0x50
       [<ffffffff81146d8d>] do_sys_open+0x16d/0x1d0
       [<ffffffff81146e10>] sys_open+0x20/0x30
       [<ffffffff81478f42>] system_call_fastpath+0x16/0x1b
      
      Reported-by: default avatarJohannes Berg <johannes.berg@intel.com>
      Signed-off-by: default avatarFelix Fietkau <nbd@openwrt.org>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      d8c7aae6
    • Johannes Berg's avatar
      mac80211: clean up remain-on-channel on interface stop · 71ecfa18
      Johannes Berg authored
      
      
      When any interface goes down, it could be the one that we
      were doing a remain-on-channel with. We therefore need to
      cancel the remain-on-channel and flush the related work
      structs so they don't run after the interface has been
      removed or even destroyed.
      
      It's also possible in this case that an off-channel SKB
      was never transmitted, so free it if this is the case.
      Note that this can also happen if the driver finishes
      the off-channel period without ever starting it.
      
      Cc: stable@kernel.org
      Reported-by: default avatarNirav Shah <nirav.j2.shah@intel.com>
      Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      71ecfa18
    • Johannes Berg's avatar
      mac80211_hwsim: advertise interface combinations · 1ae2fc25
      Johannes Berg authored
      
      
      Enforcing interface combinations broke uses of hwsim
      with multiple virtual interfaces. Advertise that all
      combinations are possible to fix this.
      
      Reported-by: default avatarNirav Shah <nirav.j2.shah@intel.com>
      Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      1ae2fc25
    • Meenakshi Venkataraman's avatar
      mac80211: fix error in station state transitions during reconfig · bd34ab62
      Meenakshi Venkataraman authored
      
      
      As part of hardware reconfig mac80211 tries
      to restore the station state to its values
      before the hardware reconfig, but it only
      goes to the last-state - 1. Fix this
      off-by-one error.
      
      Cc: stable@kernel.org [3.4]
      Signed-off-by: default avatarMeenakshi Venkataraman <meenakshi.venkataraman@intel.com>
      Reviewed-by: default avatarEmmanuel Grumbach <emmanuel.grumbach@intel.com>
      Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      bd34ab62
    • Johannes Berg's avatar
      iwlwifi: fix TX power antenna access · a5fdde28
      Johannes Berg authored
      
      
      Since my commit
        iwlwifi: use valid TX/RX antenna from hw_params
      the config values are pure overrides, not the
      real values for all hardware. Therefore, the
      EEPROM TX power reading code checks the wrong
      values, it should check the hw_params values.
      
      Cc: stable@kernel.org [3.4]
      Reviewed-by: default avatarEmmanuel Grumbach <emmanuel.grumbach@intel.com>
      Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      a5fdde28
    • Chun-Yeow Yeoh's avatar
      mac80211: Fix Unreachable Mesh Station Problem when joining to another MBSS · b8bacc18
      Chun-Yeow Yeoh authored
      
      
      Mesh station that joins an MBSS is reachable using mesh portal with 6
      address frame by mesh stations from another MBSS if these two different
      MBSSes are bridged. However, if the mesh station later moves into the
      same MBSS of those mesh stations, it is unreachable by mesh stations
      in the MBSS due to the mpp_paths table is not deleted. A quick fix
      is to perform mesh_path_lookup, if it is available for the target
      destination, mpp_path_lookup is not performed. When the mesh station
      moves back to its original MBSS, the mesh_paths will be deleted once
      expired. So, it will be reachable using mpp_path_lookup again.
      
      Signed-off-by: default avatarChun-Yeow Yeoh <yeohchunyeow@gmail.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      b8bacc18
    • Amitkumar Karwar's avatar
      cfg80211: use sme_state in ibss start/join path · 28f33366
      Amitkumar Karwar authored
      
      
      CFG80211_DEV_WARN_ON() at "net/wireless/ibss.c line 63"
      is unnecessarily triggered even after successful connection,
      when cfg80211_ibss_joined() is called by driver inside
      .join_ibss handler.
      
      This patch fixes the problem by changing 'sme_state' in ibss path
      and having WARN_ON() check for 'sme_state' similar to infra
      association.
      
      Signed-off-by: default avatarAmitkumar Karwar <akarwar@marvell.com>
      Signed-off-by: default avatarBing Zhao <bzhao@marvell.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      28f33366
    • Avinash Patil's avatar
      mwifiex: support NL80211_HIDDEN_SSID_ZERO_LEN for uAP · 7a1c9934
      Avinash Patil authored
      
      
      mwifiex uAP supports NL80211_HIDDEN_SSID_ZERO_LEN type of hidden
      SSID only. NL80211_HIDDEN_SSID_ZERO_CONTENTS is not supported.
      
      Signed-off-by: default avatarAvinash Patil <patila@marvell.com>
      Signed-off-by: default avatarKiran Divekar <dkiran@marvell.com>
      Signed-off-by: default avatarBing Zhao <bzhao@marvell.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      7a1c9934
    • Avinash Patil's avatar
      mwifiex: invalidate bss config before setting channel for uAP · f0e3bd23
      Avinash Patil authored
      
      
      Mark bss_config parameters as invalid before setting AP channel.
      This prevents from setting invalid parameters while setting AP
      channel to FW.
      
      Signed-off-by: default avatarAvinash Patil <patila@marvell.com>
      Signed-off-by: default avatarKiran Divekar <dkiran@marvell.com>
      Signed-off-by: default avatarBing Zhao <bzhao@marvell.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      f0e3bd23
    • Stanislaw Gruszka's avatar
      mac80211: run scan after finish connection monitoring · 925e64c3
      Stanislaw Gruszka authored
      commit 133d40f9
      
      
      Author: Stanislaw Gruszka <sgruszka@redhat.com>
      Date:   Wed Mar 28 16:01:19 2012 +0200
      
          mac80211: do not scan and monitor connection in parallel
      
      add bug, which make possible to start a scan and never finish it, so
      make every new scanning request finish with -EBUSY error. This can
      happen on code paths where we finish connection monitoring and clear
      IEEE80211_STA_*_POLL flags, but do not check if scan was deferred.
      This patch fixes those code paths.
      
      Signed-off-by: default avatarStanislaw Gruszka <sgruszka@redhat.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      925e64c3
  6. Jun 03, 2012
    • Linus Torvalds's avatar
      Linux 3.5-rc1 · f8f5701b
      Linus Torvalds authored
      v3.5-rc1
      f8f5701b
    • Linus Torvalds's avatar
      Merge tag 'dm-3.5-changes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm · 912afc36
      Linus Torvalds authored
      Pull device-mapper updates from Alasdair G Kergon:
       "Improve multipath's retrying mechanism in some defined circumstances
        and provide a simple reserve/release mechanism for userspace tools to
        access thin provisioning metadata while the pool is in use."
      
      * tag 'dm-3.5-changes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm:
        dm thin: provide userspace access to pool metadata
        dm thin: use slab mempools
        dm mpath: allow ioctls to trigger pg init
        dm mpath: delay retry of bypassed pg
        dm mpath: reduce size of struct multipath
      912afc36
    • Joe Thornber's avatar
      dm thin: provide userspace access to pool metadata · cc8394d8
      Joe Thornber authored
      
      
      This patch implements two new messages that can be sent to the thin
      pool target allowing it to take a snapshot of the _metadata_.  This,
      read-only snapshot can be accessed by userland, concurrently with the
      live target.
      
      Only one metadata snapshot can be held at a time.  The pool's status
      line will give the block location for the current msnap.
      
      Since version 0.1.5 of the userland thin provisioning tools, the
      thin_dump program displays the msnap as follows:
      
          thin_dump -m <msnap root> <metadata dev>
      
      Available here: https://github.com/jthornber/thin-provisioning-tools
      
      Now that userland can access the metadata we can do various things
      that have traditionally been kernel side tasks:
      
           i) Incremental backups.
      
           By using metadata snapshots we can work out what blocks have
           changed over time.  Combined with data snapshots we can ensure
           the data doesn't change while we back it up.
      
           A short proof of concept script can be found here:
      
           https://github.com/jthornber/thinp-test-suite/blob/master/incremental_backup_example.rb
      
           ii) Migration of thin devices from one pool to another.
      
           iii) Merging snapshots back into an external origin.
      
           iv) Asyncronous replication.
      
      Signed-off-by: default avatarJoe Thornber <ejt@redhat.com>
      Signed-off-by: default avatarAlasdair G Kergon <agk@redhat.com>
      cc8394d8
    • Mike Snitzer's avatar
      dm thin: use slab mempools · a24c2569
      Mike Snitzer authored
      
      
      Use dedicated caches prefixed with a "dm_" name rather than relying on
      kmalloc mempools backed by generic slab caches so the memory usage of
      thin provisioning (and any leaks) can be accounted for independently.
      
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Signed-off-by: default avatarAlasdair G Kergon <agk@redhat.com>
      a24c2569
    • Mikulas Patocka's avatar
      dm mpath: allow ioctls to trigger pg init · 35991652
      Mikulas Patocka authored
      
      
      After the failure of a group of paths, any alternative paths that
      need initialising do not become available until further I/O is sent to
      the device.  Until this has happened, ioctls return -EAGAIN.
      
      With this patch, new paths are made available in response to an ioctl
      too.  The processing of the ioctl gets delayed until this has happened.
      
      Instead of returning an error, we submit a work item to kmultipathd
      (that will potentially activate the new path) and retry in ten
      milliseconds.
      
      Note that the patch doesn't retry an ioctl if the ioctl itself fails due
      to a path failure.  Such retries should be handled intelligently by the
      code that generated the ioctl in the first place, noting that some SCSI
      commands should not be retried because they are not idempotent (XOR write
      commands).  For commands that could be retried, there is a danger that
      if the device rejected the SCSI command, the path could be errorneously
      marked as failed, and the request would be retried on another path which
      might fail too.  It can be determined if the failure happens on the
      device or on the SCSI controller, but there is no guarantee that all
      SCSI drivers set these flags correctly.
      
      Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
      Signed-off-by: default avatarAlasdair G Kergon <agk@redhat.com>
      35991652