signal_pending() set without a signal?

lee_merrill_at_yahoo.com
Date: 09/15/05

  • Next message: Kasper Dupont: "Re: Ever seen OOM killer pick a process while it is core dumping to tmpfs?" 
    Date: 15 Sep 2005 14:02:21 -0700

    Hi everyone,
        It looks like I am getting signal_pending() true sometimes, when a
    signal is not set (checking via dequeue_signal() returns no signal).
    Yet code is being called in the kernel which does a
    set_tsk_thread_flag(... TIF_SIGPENDING):

        recalc_sigpending_tsk line 229
        do_sigaction+0x184/0x210
        sys_rt_sigaction+0x88/0x100
        smp_apic_timer_interrupt+0xea/0x160

    Apparently (t->signal->group_stop_count > 0 ||
                PENDING(&t->pending, &t->blocked) ||
                PENDING(&t->signal->shared_pending, &t->blocked))
    is true.

    Yet checking for an active signal in recalc_sigpending_tsk doesn't turn
    up an active signal, and when the driver sees signal_pending(), no
    active signal is present then, either. So this causes my driver to
    think it should stop and return an error, when apparently it shouldn't,
    because there doesn't seem to be a signal set, also, the application
    calling the driver doesn't use signals, and shouldn't be getting them.

    So any suggestions on this would be appreciated...

    Thanks,
    Lee

  • Next message: Kasper Dupont: "Re: Ever seen OOM killer pick a process while it is core dumping to tmpfs?"

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