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    Subject[RT] Race condition on bug output.
    Hi Ingo,

    I found a race condition in my kernel which can also be found in yours.
    When I trigger the printk in check_periodic_interval, interrupts are
    turned on in release_console_sem. Unfortunately, this can have an
    interrupt go off there (since they are turned back on there) and the
    write_lock system_time_lock will be taken again, thus producing a

    I'm not sure if this is the best solution, but this was the easiest.

    Maybe the CONFIG_PARANOID_GENERIC_TIME should be added in the warnings
    in init/main.c too?

    Since interrupts are kept off in the ktimer (hrtimer, whatever) in
    printk, this does not affect those patches. This is a PREEMPT_RT only

    -- Steve

    Index: linux-2.6.14-rt22/kernel/printk.c
    --- linux-2.6.14-rt22.orig/kernel/printk.c 2005-12-06 21:44:53.000000000 -0500
    +++ linux-2.6.14-rt22/kernel/printk.c 2005-12-06 21:52:11.000000000 -0500
    @@ -757,7 +757,8 @@
    * on PREEMPT_RT, call console drivers with
    * interrupts enabled (unless we are debugging):
    -#if defined(CONFIG_PREEMPT_RT) && !defined(CONFIG_PRINTK_IGNORE_LOGLEVEL) && !defined(CONFIG_PPC)
    +#if defined(CONFIG_PREEMPT_RT) && !defined(CONFIG_PRINTK_IGNORE_LOGLEVEL) && !defined(CONFIG_PPC) \

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      Last update: 2005-12-07 04:37    [W:0.022 / U:7.812 seconds]
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