1. 07 3月, 2012 2 次提交
    • I
      Merge tag 'mce-fix-for-3.3-rc6' of... · a5c2edf5
      Ingo Molnar 提交于
      Merge tag 'mce-fix-for-3.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras into x86/urgent
      
      Fix a reproducible RCU warning in the MCE code
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      a5c2edf5
    • S
      x86, mce: Fix rcu splat in drain_mce_log_buffer() · b11e3d78
      Srivatsa S. Bhat 提交于
      While booting, the following message is seen:
      
      [   21.665087] ===============================
      [   21.669439] [ INFO: suspicious RCU usage. ]
      [   21.673798] 3.2.0-0.0.0.28.36b5ec9-default #2 Not tainted
      [   21.681353] -------------------------------
      [   21.685864] arch/x86/kernel/cpu/mcheck/mce.c:194 suspicious rcu_dereference_index_check() usage!
      [   21.695013]
      [   21.695014] other info that might help us debug this:
      [   21.695016]
      [   21.703488]
      [   21.703489] rcu_scheduler_active = 1, debug_locks = 1
      [   21.710426] 3 locks held by modprobe/2139:
      [   21.714754]  #0:  (&__lockdep_no_validate__){......}, at: [<ffffffff8133afd3>] __driver_attach+0x53/0xa0
      [   21.725020]  #1:
      [   21.725323] ioatdma: Intel(R) QuickData Technology Driver 4.00
      [   21.733206]  (&__lockdep_no_validate__){......}, at: [<ffffffff8133afe1>] __driver_attach+0x61/0xa0
      [   21.743015]  #2:  (i7core_edac_lock){+.+.+.}, at: [<ffffffffa01cfa5f>] i7core_probe+0x1f/0x5c0 [i7core_edac]
      [   21.753708]
      [   21.753709] stack backtrace:
      [   21.758429] Pid: 2139, comm: modprobe Not tainted 3.2.0-0.0.0.28.36b5ec9-default #2
      [   21.768253] Call Trace:
      [   21.770838]  [<ffffffff810977cd>] lockdep_rcu_suspicious+0xcd/0x100
      [   21.777366]  [<ffffffff8101aa41>] drain_mcelog_buffer+0x191/0x1b0
      [   21.783715]  [<ffffffff8101aa78>] mce_register_decode_chain+0x18/0x20
      [   21.790430]  [<ffffffffa01cf8db>] i7core_register_mci+0x2fb/0x3e4 [i7core_edac]
      [   21.798003]  [<ffffffffa01cfb14>] i7core_probe+0xd4/0x5c0 [i7core_edac]
      [   21.804809]  [<ffffffff8129566b>] local_pci_probe+0x5b/0xe0
      [   21.810631]  [<ffffffff812957c9>] __pci_device_probe+0xd9/0xe0
      [   21.816650]  [<ffffffff813362e4>] ? get_device+0x14/0x20
      [   21.822178]  [<ffffffff81296916>] pci_device_probe+0x36/0x60
      [   21.828061]  [<ffffffff8133ac8a>] really_probe+0x7a/0x2b0
      [   21.833676]  [<ffffffff8133af23>] driver_probe_device+0x63/0xc0
      [   21.839868]  [<ffffffff8133b01b>] __driver_attach+0x9b/0xa0
      [   21.845718]  [<ffffffff8133af80>] ? driver_probe_device+0xc0/0xc0
      [   21.852027]  [<ffffffff81339168>] bus_for_each_dev+0x68/0x90
      [   21.857876]  [<ffffffff8133aa3c>] driver_attach+0x1c/0x20
      [   21.863462]  [<ffffffff8133a64d>] bus_add_driver+0x16d/0x2b0
      [   21.869377]  [<ffffffff8133b6dc>] driver_register+0x7c/0x160
      [   21.875220]  [<ffffffff81296bda>] __pci_register_driver+0x6a/0xf0
      [   21.881494]  [<ffffffffa01fe000>] ? 0xffffffffa01fdfff
      [   21.886846]  [<ffffffffa01fe047>] i7core_init+0x47/0x1000 [i7core_edac]
      [   21.893737]  [<ffffffff810001ce>] do_one_initcall+0x3e/0x180
      [   21.899670]  [<ffffffff810a9b95>] sys_init_module+0xc5/0x220
      [   21.905542]  [<ffffffff8149bc39>] system_call_fastpath+0x16/0x1b
      
      Fix this by using ACCESS_ONCE() instead of rcu_dereference_check_mce()
      over mcelog.next. Since the access to each entry is controlled by the
      ->finished field, ACCESS_ONCE() should work just fine. An rcu_dereference
      is unnecessary here.
      Signed-off-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
      Suggested-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Signed-off-by: NBorislav Petkov <borislav.petkov@amd.com>
      b11e3d78
  2. 04 3月, 2012 6 次提交
  3. 03 3月, 2012 13 次提交
  4. 02 3月, 2012 8 次提交
  5. 01 3月, 2012 11 次提交