Hi people!
I have a kernel module working on kernel 2.2.14(RedHat 6.2)...
When interrupt occurs, special signal sends to the user process in the bottom-half of the interrupt handler.
And i have a corruption of signal information when signal come to the user handler
Signal sending:
...
struct XXX_cbd
{
unsigned long signature;
void (*isr)(void);
struct sigaction sa;
sigset_t mask;
};
...
struct siginfo info;
info.si_signo = dev->callback[channel].signo;
info.si_errno = channel;
info.si_code = SI_MESGQ; // must be < 0 for info.si_ptr
info.si_pid = 0; /* sending from kernel */
info.si_uid = 0;
info.si_ptr = dev->callback[channel].context; /* XXX_cbd struct */
send_sig_info(info.si_signo, &info, dev->callback[channel].process);
...
In user process in signal handler this signal is catched:
...
static void XXX_signal_handler(int signo, siginfo_t * siginfo, void * arg)
{
if(signo == SIGUSR2 && siginfo->si_signo == SIGUSR2 &&
siginfo->si_code == SI_MESGQ && siginfo->si_pid == 0 && siginfo->si_uid == 0)
{
struct XXX_cbd * cptr = (struct DM6420HR_cbd *)siginfo->si_ptr;
if(cptr->signature == magic_signature && cptr->isr != NULL)
(*cptr->isr)();
}
}
...
But there is strange things:
siginfo->si_code is 0 instead of SI_MESGQ
siginfo->si_uid not equal 0
and siginfo->si_ptr is 0 instead of valid pointer.
What a problem here?
PS.
In RedHat 7.3 ( kernel 2.4.18) all works fine.
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