1. 22 9月, 2014 2 次提交
    • P
      cpufreq: release policy->rwsem on error · 7106e02b
      Prarit Bhargava 提交于
      While debugging a cpufreq-related hardware failure on a system I saw the
      following lockdep warning:
      
       =========================
       [ BUG: held lock freed! ] 3.17.0-rc4+ #1 Tainted: G            E
       -------------------------
       insmod/2247 is freeing memory ffff88006e1b1400-ffff88006e1b17ff, with a lock still held there!
        (&policy->rwsem){+.+...}, at: [<ffffffff8156d37d>] __cpufreq_add_dev.isra.21+0x47d/0xb80
       3 locks held by insmod/2247:
        #0:  (subsys mutex#5){+.+.+.}, at: [<ffffffff81485579>] subsys_interface_register+0x69/0x120
        #1:  (cpufreq_rwsem){.+.+.+}, at: [<ffffffff8156cf73>] __cpufreq_add_dev.isra.21+0x73/0xb80
        #2:  (&policy->rwsem){+.+...}, at: [<ffffffff8156d37d>] __cpufreq_add_dev.isra.21+0x47d/0xb80
      
       stack backtrace:
       CPU: 0 PID: 2247 Comm: insmod Tainted: G            E  3.17.0-rc4+ #1
       Hardware name: HP ProLiant MicroServer Gen8, BIOS J06 08/24/2013
        0000000000000000 000000008f3063c4 ffff88006f87bb30 ffffffff8171b358
        ffff88006bcf3750 ffff88006f87bb68 ffffffff810e09e1 ffff88006e1b1400
        ffffea0001b86c00 ffffffff8156d327 ffff880073003500 0000000000000246
       Call Trace:
        [<ffffffff8171b358>] dump_stack+0x4d/0x66
        [<ffffffff810e09e1>] debug_check_no_locks_freed+0x171/0x180
        [<ffffffff8156d327>] ? __cpufreq_add_dev.isra.21+0x427/0xb80
        [<ffffffff8121412b>] kfree+0xab/0x2b0
        [<ffffffff8156d327>] __cpufreq_add_dev.isra.21+0x427/0xb80
        [<ffffffff81724cf7>] ? _raw_spin_unlock+0x27/0x40
        [<ffffffffa003517f>] ? pcc_cpufreq_do_osc+0x17f/0x17f [pcc_cpufreq]
        [<ffffffff8156da8e>] cpufreq_add_dev+0xe/0x10
        [<ffffffff814855d1>] subsys_interface_register+0xc1/0x120
        [<ffffffff8156bcf2>] cpufreq_register_driver+0x112/0x340
        [<ffffffff8121415a>] ? kfree+0xda/0x2b0
        [<ffffffffa003517f>] ? pcc_cpufreq_do_osc+0x17f/0x17f [pcc_cpufreq]
        [<ffffffffa003562e>] pcc_cpufreq_init+0x4af/0xe81 [pcc_cpufreq]
        [<ffffffffa003517f>] ? pcc_cpufreq_do_osc+0x17f/0x17f [pcc_cpufreq]
        [<ffffffff81002144>] do_one_initcall+0xd4/0x210
        [<ffffffff811f7472>] ? __vunmap+0xd2/0x120
        [<ffffffff81127155>] load_module+0x1315/0x1b70
        [<ffffffff811222a0>] ? store_uevent+0x70/0x70
        [<ffffffff811229d9>] ? copy_module_from_fd.isra.44+0x129/0x180
        [<ffffffff81127b86>] SyS_finit_module+0xa6/0xd0
        [<ffffffff81725b69>] system_call_fastpath+0x16/0x1b
       cpufreq: __cpufreq_add_dev: ->get() failed
      insmod: ERROR: could not insert module pcc-cpufreq.ko: No such device
      
      The warning occurs in the __cpufreq_add_dev() code which does
      
              down_write(&policy->rwsem);
      	...
              if (cpufreq_driver->get && !cpufreq_driver->setpolicy) {
                      policy->cur = cpufreq_driver->get(policy->cpu);
                      if (!policy->cur) {
                              pr_err("%s: ->get() failed\n", __func__);
                              goto err_get_freq;
                      }
      
      If cpufreq_driver->get(policy->cpu) returns an error we execute the
      code at err_get_freq, which does not up the policy->rwsem.  This causes
      the lockdep warning.
      
      Trivial patch to up the policy->rwsem in the error path.
      
      After the patch has been applied, and an error occurs in the
      cpufreq_driver->get(policy->cpu) call we will now see
      
      cpufreq: __cpufreq_add_dev: ->get() failed
      cpufreq: __cpufreq_add_dev: ->get() failed
      modprobe: ERROR: could not insert 'pcc_cpufreq': No such device
      
      Fixes: 4e97b631 (cpufreq: Initialize governor for a new policy under policy->rwsem)
      Signed-off-by: NPrarit Bhargava <prarit@redhat.com>
      Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
      Cc: 3.14+ <stable@vger.kernel.org> # 3.14+
      Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
      7106e02b
    • L
      cpufreq: fix cpufreq suspend/resume for intel_pstate · 8e30444e
      Lan Tianyu 提交于
      Cpufreq core introduces cpufreq_suspended flag to let cpufreq sysfs nodes
      across S2RAM/S2DISK. But the flag is only set in the cpufreq_suspend()
      for cpufreq drivers which have target or target_index callback. This
      skips intel_pstate driver. This patch is to set the flag before checking
      target or target_index callback.
      
      Fixes: 2f0aea93 (cpufreq: suspend governors on system suspend/hibernate)
      Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
      Cc: 3.15+ <stable@vger.kernel.org> # 3.15+
      [rjw: Subject]
      Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
      8e30444e
  2. 20 9月, 2014 8 次提交
  3. 19 9月, 2014 12 次提交
  4. 18 9月, 2014 5 次提交
  5. 17 9月, 2014 4 次提交
  6. 16 9月, 2014 6 次提交
  7. 15 9月, 2014 3 次提交