1. 07 3月, 2012 1 次提交
    • 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. 23 2月, 2012 2 次提交
  3. 17 1月, 2012 1 次提交
  4. 14 1月, 2012 1 次提交
  5. 04 1月, 2012 4 次提交
    • T
      x86/mce: Handle "action required" errors · a8c321fb
      Tony Luck 提交于
      All non-urgent actions (reporting low severity errors and handling
      "action-optional" errors) are now handled by a work queue. This
      means that TIF_MCE_NOTIFY can be used to block execution for a
      thread experiencing an "action-required" fault until we get all
      cpus out of the machine check handler (and the thread that hit
      the fault into mce_notify_process().
      
      We use the new mce_{save,find,clear}_info() API to get information
      from do_machine_check() to mce_notify_process(), and then use the
      newly improved memory_failure(..., MF_ACTION_REQUIRED) to handle
      the error (possibly signalling the process).
      
      Update some comments to make the new code flows clearer.
      Signed-off-by: NTony Luck <tony.luck@intel.com>
      a8c321fb
    • T
      x86/mce: Add mechanism to safely save information in MCE handler · af104e39
      Tony Luck 提交于
      Machine checks on Intel cpus interrupt execution on all cpus, regardless
      of interrupt masking.  We have a need to save some data about the cause
      of the machine check (physical address) in the machine check handler that
      can be retrieved later to attempt recovery in a more flexible execution
      state.
      Signed-off-by: NTony Luck <tony.luck@intel.com>
      af104e39
    • T
      x86/mce: Create helper function to save addr/misc when needed · 85f92694
      Tony Luck 提交于
      The MCI_STATUS_MISCV and MCI_STATUS_ADDRV bits in the bank status
      registers define whether the MISC and ADDR registers respectively
      contain valid data - provide a helper function to check these bits
      and read the registers when needed.
      
      In addition, processors that support software error recovery (as
      indicated by the MCG_SER_P bit in the MCG_CAP register) may include
      some undefined bits in the ADDR register - mask these out.
      Acked-by: NBorislav Petkov <bp@amd64.org>
      Signed-off-by: NTony Luck <tony.luck@intel.com>
      85f92694
    • T
      HWPOISON: Clean up memory_failure() vs. __memory_failure() · cd42f4a3
      Tony Luck 提交于
      There is only one caller of memory_failure(), all other users call
      __memory_failure() and pass in the flags argument explicitly. The
      lone user of memory_failure() will soon need to pass flags too.
      
      Add flags argument to the callsite in mce.c. Delete the old memory_failure()
      function, and then rename __memory_failure() without the leading "__".
      
      Provide clearer message when action optional memory errors are ignored.
      Acked-by: NBorislav Petkov <bp@amd64.org>
      Signed-off-by: NTony Luck <tony.luck@intel.com>
      cd42f4a3
  6. 22 12月, 2011 1 次提交
    • K
      cpu: convert 'cpu' and 'machinecheck' sysdev_class to a regular subsystem · 8a25a2fd
      Kay Sievers 提交于
      This moves the 'cpu sysdev_class' over to a regular 'cpu' subsystem
      and converts the devices to regular devices. The sysdev drivers are
      implemented as subsystem interfaces now.
      
      After all sysdev classes are ported to regular driver core entities, the
      sysdev implementation will be entirely removed from the kernel.
      
      Userspace relies on events and generic sysfs subsystem infrastructure
      from sysdev devices, which are made available with this conversion.
      
      Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
      Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Chris Metcalf <cmetcalf@tilera.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Borislav Petkov <bp@amd64.org>
      Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
      Cc: Len Brown <lenb@kernel.org>
      Cc: Zhang Rui <rui.zhang@intel.com>
      Cc: Dave Jones <davej@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Russell King <rmk+kernel@arm.linux.org.uk>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Arjan van de Ven <arjan@linux.intel.com>
      Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
      Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
      Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      8a25a2fd
  7. 21 12月, 2011 1 次提交
  8. 14 12月, 2011 2 次提交
  9. 08 11月, 2011 1 次提交
  10. 01 11月, 2011 3 次提交
  11. 19 10月, 2011 1 次提交
  12. 14 10月, 2011 1 次提交
  13. 10 10月, 2011 1 次提交
  14. 14 9月, 2011 1 次提交
    • H
      x86, mce: Do not call del_timer_sync() in IRQ context · 9aaef96f
      Hidetoshi Seto 提交于
      del_timer_sync() can cause a deadlock when called in interrupt context.
      It is used with on_each_cpu() in some parts for sysfs files like bank*,
      check_interval, cmci_disabled and ignore_ce.
      
      However, use of on_each_cpu() results in calling the function passed
      as the argument in interrupt context. This causes a flood of nested
      warnings from del_timer_sync() (it runs on each CPU) caused even by a
      simple file access like:
      
      $ echo 300 > /sys/devices/system/machinecheck/machinecheck0/check_interval
      
      Fortunately, these MCE-specific files are rarely used and AFAIK only few
      MCE geeks experience this warning.
      
      To remove the warning, move timer deletion outside of the interrupt
      context.
      Signed-off-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
      Signed-off-by: NBorislav Petkov <borislav.petkov@amd.com>
      9aaef96f
  15. 16 6月, 2011 8 次提交
  16. 21 4月, 2011 1 次提交
  17. 20 4月, 2011 1 次提交
  18. 01 4月, 2011 1 次提交
  19. 24 3月, 2011 1 次提交
    • R
      x86: Use syscore_ops instead of sysdev classes and sysdevs · f3c6ea1b
      Rafael J. Wysocki 提交于
      Some subsystems in the x86 tree need to carry out suspend/resume and
      shutdown operations with one CPU on-line and interrupts disabled and
      they define sysdev classes and sysdevs or sysdev drivers for this
      purpose.  This leads to unnecessarily complicated code and excessive
      memory usage, so switch them to using struct syscore_ops objects for
      this purpose instead.
      
      Generally, there are three categories of subsystems that use
      sysdevs for implementing PM operations: (1) subsystems whose
      suspend/resume callbacks ignore their arguments entirely (the
      majority), (2) subsystems whose suspend/resume callbacks use their
      struct sys_device argument, but don't really need to do that,
      because they can be implemented differently in an arguably simpler
      way (io_apic.c), and (3) subsystems whose suspend/resume callbacks
      use their struct sys_device argument, but the value of that argument
      is always the same and could be ignored (microcode_core.c).  In all
      of these cases the subsystems in question may be readily converted to
      using struct syscore_ops objects for power management and shutdown.
      Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
      Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
      Acked-by: NIngo Molnar <mingo@elte.hu>
      f3c6ea1b
  20. 18 3月, 2011 1 次提交
  21. 30 12月, 2010 2 次提交
  22. 15 10月, 2010 1 次提交
    • A
      llseek: automatically add .llseek fop · 6038f373
      Arnd Bergmann 提交于
      All file_operations should get a .llseek operation so we can make
      nonseekable_open the default for future file operations without a
      .llseek pointer.
      
      The three cases that we can automatically detect are no_llseek, seq_lseek
      and default_llseek. For cases where we can we can automatically prove that
      the file offset is always ignored, we use noop_llseek, which maintains
      the current behavior of not returning an error from a seek.
      
      New drivers should normally not use noop_llseek but instead use no_llseek
      and call nonseekable_open at open time.  Existing drivers can be converted
      to do the same when the maintainer knows for certain that no user code
      relies on calling seek on the device file.
      
      The generated code is often incorrectly indented and right now contains
      comments that clarify for each added line why a specific variant was
      chosen. In the version that gets submitted upstream, the comments will
      be gone and I will manually fix the indentation, because there does not
      seem to be a way to do that using coccinelle.
      
      Some amount of new code is currently sitting in linux-next that should get
      the same modifications, which I will do at the end of the merge window.
      
      Many thanks to Julia Lawall for helping me learn to write a semantic
      patch that does all this.
      
      ===== begin semantic patch =====
      // This adds an llseek= method to all file operations,
      // as a preparation for making no_llseek the default.
      //
      // The rules are
      // - use no_llseek explicitly if we do nonseekable_open
      // - use seq_lseek for sequential files
      // - use default_llseek if we know we access f_pos
      // - use noop_llseek if we know we don't access f_pos,
      //   but we still want to allow users to call lseek
      //
      @ open1 exists @
      identifier nested_open;
      @@
      nested_open(...)
      {
      <+...
      nonseekable_open(...)
      ...+>
      }
      
      @ open exists@
      identifier open_f;
      identifier i, f;
      identifier open1.nested_open;
      @@
      int open_f(struct inode *i, struct file *f)
      {
      <+...
      (
      nonseekable_open(...)
      |
      nested_open(...)
      )
      ...+>
      }
      
      @ read disable optional_qualifier exists @
      identifier read_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      expression E;
      identifier func;
      @@
      ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
      {
      <+...
      (
         *off = E
      |
         *off += E
      |
         func(..., off, ...)
      |
         E = *off
      )
      ...+>
      }
      
      @ read_no_fpos disable optional_qualifier exists @
      identifier read_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      @@
      ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
      {
      ... when != off
      }
      
      @ write @
      identifier write_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      expression E;
      identifier func;
      @@
      ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
      {
      <+...
      (
        *off = E
      |
        *off += E
      |
        func(..., off, ...)
      |
        E = *off
      )
      ...+>
      }
      
      @ write_no_fpos @
      identifier write_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      @@
      ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
      {
      ... when != off
      }
      
      @ fops0 @
      identifier fops;
      @@
      struct file_operations fops = {
       ...
      };
      
      @ has_llseek depends on fops0 @
      identifier fops0.fops;
      identifier llseek_f;
      @@
      struct file_operations fops = {
      ...
       .llseek = llseek_f,
      ...
      };
      
      @ has_read depends on fops0 @
      identifier fops0.fops;
      identifier read_f;
      @@
      struct file_operations fops = {
      ...
       .read = read_f,
      ...
      };
      
      @ has_write depends on fops0 @
      identifier fops0.fops;
      identifier write_f;
      @@
      struct file_operations fops = {
      ...
       .write = write_f,
      ...
      };
      
      @ has_open depends on fops0 @
      identifier fops0.fops;
      identifier open_f;
      @@
      struct file_operations fops = {
      ...
       .open = open_f,
      ...
      };
      
      // use no_llseek if we call nonseekable_open
      ////////////////////////////////////////////
      @ nonseekable1 depends on !has_llseek && has_open @
      identifier fops0.fops;
      identifier nso ~= "nonseekable_open";
      @@
      struct file_operations fops = {
      ...  .open = nso, ...
      +.llseek = no_llseek, /* nonseekable */
      };
      
      @ nonseekable2 depends on !has_llseek @
      identifier fops0.fops;
      identifier open.open_f;
      @@
      struct file_operations fops = {
      ...  .open = open_f, ...
      +.llseek = no_llseek, /* open uses nonseekable */
      };
      
      // use seq_lseek for sequential files
      /////////////////////////////////////
      @ seq depends on !has_llseek @
      identifier fops0.fops;
      identifier sr ~= "seq_read";
      @@
      struct file_operations fops = {
      ...  .read = sr, ...
      +.llseek = seq_lseek, /* we have seq_read */
      };
      
      // use default_llseek if there is a readdir
      ///////////////////////////////////////////
      @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier readdir_e;
      @@
      // any other fop is used that changes pos
      struct file_operations fops = {
      ... .readdir = readdir_e, ...
      +.llseek = default_llseek, /* readdir is present */
      };
      
      // use default_llseek if at least one of read/write touches f_pos
      /////////////////////////////////////////////////////////////////
      @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier read.read_f;
      @@
      // read fops use offset
      struct file_operations fops = {
      ... .read = read_f, ...
      +.llseek = default_llseek, /* read accesses f_pos */
      };
      
      @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier write.write_f;
      @@
      // write fops use offset
      struct file_operations fops = {
      ... .write = write_f, ...
      +	.llseek = default_llseek, /* write accesses f_pos */
      };
      
      // Use noop_llseek if neither read nor write accesses f_pos
      ///////////////////////////////////////////////////////////
      
      @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier read_no_fpos.read_f;
      identifier write_no_fpos.write_f;
      @@
      // write fops use offset
      struct file_operations fops = {
      ...
       .write = write_f,
       .read = read_f,
      ...
      +.llseek = noop_llseek, /* read and write both use no f_pos */
      };
      
      @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier write_no_fpos.write_f;
      @@
      struct file_operations fops = {
      ... .write = write_f, ...
      +.llseek = noop_llseek, /* write uses no f_pos */
      };
      
      @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier read_no_fpos.read_f;
      @@
      struct file_operations fops = {
      ... .read = read_f, ...
      +.llseek = noop_llseek, /* read uses no f_pos */
      };
      
      @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      @@
      struct file_operations fops = {
      ...
      +.llseek = noop_llseek, /* no read or write fn */
      };
      ===== End semantic patch =====
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Cc: Julia Lawall <julia@diku.dk>
      Cc: Christoph Hellwig <hch@infradead.org>
      6038f373
  23. 03 8月, 2010 1 次提交
  24. 15 6月, 2010 1 次提交
    • P
      mce: convert to rcu_dereference_index_check() · ec8c27e0
      Paul E. McKenney 提交于
      The mce processing applies rcu_dereference_check() to integers used as
      array indices.  This patch therefore moves mce to the new RCU API
      rcu_dereference_index_check() that avoids the sparse processing that
      would otherwise result in compiler errors.
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      ec8c27e0
  25. 11 6月, 2010 1 次提交