1. 22 9月, 2020 38 次提交
  2. 18 9月, 2020 2 次提交
    • L
      uio: free uio id after uio file node is freed · 8fd0e2a6
      Lang Dai 提交于
      uio_register_device() do two things.
      1) get an uio id from a global pool, e.g. the id is <A>
      2) create file nodes like /sys/class/uio/uio<A>
      
      uio_unregister_device() do two things.
      1) free the uio id <A> and return it to the global pool
      2) free the file node /sys/class/uio/uio<A>
      
      There is a situation is that one worker is calling uio_unregister_device(),
      and another worker is calling uio_register_device().
      If the two workers are X and Y, they go as below sequence,
      1) X free the uio id <AAA>
      2) Y get an uio id <AAA>
      3) Y create file node /sys/class/uio/uio<AAA>
      4) X free the file note /sys/class/uio/uio<AAA>
      Then it will failed at the 3rd step and cause the phenomenon we saw as it
      is creating a duplicated file node.
      
      Failure reports as follows:
      sysfs: cannot create duplicate filename '/class/uio/uio10'
      Call Trace:
         sysfs_do_create_link_sd.isra.2+0x9e/0xb0
         sysfs_create_link+0x25/0x40
         device_add+0x2c4/0x640
         __uio_register_device+0x1c5/0x576 [uio]
         adf_uio_init_bundle_dev+0x231/0x280 [intel_qat]
         adf_uio_register+0x1c0/0x340 [intel_qat]
         adf_dev_start+0x202/0x370 [intel_qat]
         adf_dev_start_async+0x40/0xa0 [intel_qat]
         process_one_work+0x14d/0x410
         worker_thread+0x4b/0x460
         kthread+0x105/0x140
       ? process_one_work+0x410/0x410
       ? kthread_bind+0x40/0x40
       ret_from_fork+0x1f/0x40
       Code: 85 c0 48 89 c3 74 12 b9 00 10 00 00 48 89 c2 31 f6 4c 89 ef
       e8 ec c4 ff ff 4c 89 e2 48 89 de 48 c7 c7 e8 b4 ee b4 e8 6a d4 d7
       ff <0f> 0b 48 89 df e8 20 fa f3 ff 5b 41 5c 41 5d 5d c3 66 0f 1f 84
      ---[ end trace a7531c1ed5269e84 ]---
       c6xxvf b002:00:00.0: Failed to register UIO devices
       c6xxvf b002:00:00.0: Failed to register UIO devices
      Signed-off-by: NLang Dai <lang.dai@intel.com>
      
      Link: https://lore.kernel.org/r/1600054002-17722-1-git-send-email-lang.dai@intel.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      8fd0e2a6
    • V
      nvmem: core: fix missing of_node_put() in of_nvmem_device_get() · b1c194dc
      Vadym Kochan 提交于
      of_parse_phandle() returns device_node with incremented ref count
      which needs to be decremented by of_node_put() when device_node
      is not used.
      
      Fixes: e2a5402e ("nvmem: Add nvmem_device based consumer apis.")
      Signed-off-by: NVadym Kochan <vadym.kochan@plvision.eu>
      Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@linaro.org>
      Link: https://lore.kernel.org/r/20200917134437.16637-5-srinivas.kandagatla@linaro.orgSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b1c194dc