Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1741706

Re: [PATCH 3/4] pci aer: fix deadlock in do_recovery

Show all headers | View raw

On 9/27/2017 5:42 PM, Govindarajulu Varadarajan wrote:
> CPU0					CPU1
> ---------------------------------------------------------------------
> __driver_attach()
> device_lock(&dev->mutex) <--- device mutex lock here
> driver_probe_device()
> pci_enable_sriov()
> pci_iov_add_virtfn()
> pci_device_add()
> 					aer_isr()		<--- pci aer error
> 					do_recovery()
> 					broadcast_error_message()
> 					pci_walk_bus()
> 					down_read(&pci_bus_sem) <--- rd sem

How about releasing the device_lock here on CPU0? or in other words keep
device_lock as short as possible?

> down_write(&pci_bus_sem) <-- stuck on wr sem
> 					report_error_detected()
> 					device_lock(&dev->mutex)<--- DEAD LOCK


-- 
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH 0/4] pci aer: fix deadlock in do_recovery Govindarajulu Varadarajan <gvaradar@cisco.com> - 2017-09-28 00:00 +0200
  [PATCH 1/4] pci: introduce __pci_walk_bus for caller with pci_bus_sem held Govindarajulu Varadarajan <gvaradar@cisco.com> - 2017-09-28 00:00 +0200
    Re: [PATCH 1/4] pci: introduce __pci_walk_bus for caller with  pci_bus_sem held Sinan Kaya <okaya@codeaurora.org> - 2017-09-28 18:20 +0200
      Re: [PATCH 1/4] pci: introduce __pci_walk_bus for caller with  pci_bus_sem held Govindarajulu Varadarajan <gvaradar@cisco.com> - 2017-09-29 02:00 +0200
  [PATCH 3/4] pci aer: fix deadlock in do_recovery Govindarajulu Varadarajan <gvaradar@cisco.com> - 2017-09-28 00:00 +0200
    Re: [PATCH 3/4] pci aer: fix deadlock in do_recovery Sinan Kaya <okaya@codeaurora.org> - 2017-09-28 18:50 +0200
      Re: [PATCH 3/4] pci aer: fix deadlock in do_recovery Govindarajulu Varadarajan <gvaradar@cisco.com> - 2017-09-29 01:50 +0200
        Re: [PATCH 3/4] pci aer: fix deadlock in do_recovery Sinan Kaya <okaya@codeaurora.org> - 2017-09-29 15:40 +0200
          Re: [PATCH 3/4] pci aer: fix deadlock in do_recovery Govindarajulu Varadarajan <gvaradar@cisco.com> - 2017-09-30 08:10 +0200
  [PATCH 4/4] lockdep: make MAX_LOCK_DEPTH configurable from Kconfig Govindarajulu Varadarajan <gvaradar@cisco.com> - 2017-09-28 00:00 +0200
    Re: [PATCH 4/4] lockdep: make MAX_LOCK_DEPTH configurable from  Kconfig Peter Zijlstra <peterz@infradead.org> - 2017-09-28 11:30 +0200
      Re: [PATCH 4/4] lockdep: make MAX_LOCK_DEPTH configurable from  Kconfig Govindarajulu Varadarajan <gvaradar@cisco.com> - 2017-09-29 02:00 +0200
        Re: [PATCH 4/4] lockdep: make MAX_LOCK_DEPTH configurable from  Kconfig Bjorn Helgaas <helgaas@kernel.org> - 2017-09-29 18:30 +0200
          Re: [PATCH 4/4] lockdep: make MAX_LOCK_DEPTH configurable from  Kconfig Govindarajulu Varadarajan <gvaradar@cisco.com> - 2017-09-30 08:10 +0200
  [PATCH 2/4] pci: code refactor pci_bus_lock/unlock/trylock Govindarajulu Varadarajan <gvaradar@cisco.com> - 2017-09-28 00:00 +0200

csiph-web