[BUG report] lockdep deadlock warning in shutdown

[BUG report] lockdep deadlock warning in shutdown

[Shaohua Li]

running 3.0-rc1, shutting down my system triggers a lockdep deadlock
warning.

The deadlock warning is triggered when executing
acpi_hw_clear_acpi_status, stack trace is something like:
...
__lock_acquire
?acpi_os_acquire_lock
lock_acquire
?acpi_os_acquire_lock
?_raw_spin_lock_irqsave
?acpi_hw_enable_runtime_gpe_block
_raw_spin_lock_irqsave
?acpi_os_acquire_lock
?acpi-hw_write
acpi_os_acquire_lock
acpi_ev_walk_gpe_list
acpi_hw_clear_acpi_status
acpi_enter_sleep_state
...
I wrote it down by hand since this is shutdown, no way to get the log.
also since the screen scrolls fast, I didn't catch another code path the
locks are taken which lockdep prints out.

Thanks,
Shaohua

RE: [BUG report] lockdep deadlock warning in shutdown

[Moore, Robert]

Adding Rafael.


>-----Original Message-----
>From: Li, Shaohua
>Sent: Thursday, June 02, 2011 8:25 PM
>To: Moore, Robert; Lin, Ming M
>Cc: linux acpi
>Subject: [BUG report] lockdep deadlock warning in shutdown
>
>running 3.0-rc1, shutting down my system triggers a lockdep deadlock
>warning.
>
>The deadlock warning is triggered when executing
>acpi_hw_clear_acpi_status, stack trace is something like:
>...
>__lock_acquire
>?acpi_os_acquire_lock
>lock_acquire
>?acpi_os_acquire_lock
>?_raw_spin_lock_irqsave
>?acpi_hw_enable_runtime_gpe_block
>_raw_spin_lock_irqsave
>?acpi_os_acquire_lock
>?acpi-hw_write
>acpi_os_acquire_lock
>acpi_ev_walk_gpe_list
>acpi_hw_clear_acpi_status
>acpi_enter_sleep_state
>...
>I wrote it down by hand since this is shutdown, no way to get the log.
>also since the screen scrolls fast, I didn't catch another code path the
>locks are taken which lockdep prints out.
>
>Thanks,
>Shaohua