Whatever resets the ttyS0 every hour isn't calling serial_core.o uart_open(). So, where should I add dump_stack() so that I am *certain* to see what PID is resetting the baud rate? Where is the "closest to the hardware" function call that sets baud? Thx, Rick On Wed, 2008-10-08 at 15:44 -0400, Rick Bolen wrote: > I've looked for cron jobs and logins, but no joy. In fact, I've > reinstalled Debian to EtchnHalf (2.6.24) and built a custom kernel > (supporting VIA C7 proc and removing SMP). > > So now I want to instrument serial_core.c to dump_stack() at every > uart_open(), and see what the stack looks like at the top-of-the-hour. > > At times, this issue has appeared on the first port of a MOXA card > (ttyMI0), but currently is presenting on ttyS0. Will modifying > uart_open() in serial_core.c catch *all* open calls on *all* serial > ports (including mxser_new, i.e. moxa driver)? > > Any recommendations or words of caution? > > Also, under Debian, is there a way for me to recompile just > serial_core.c without having to build an entire kernel? > > Thanks, > > Rick > > On Thu, 2008-09-18 at 14:59 +0200, Tosoni wrote: > > Look for 'cron' jobs > > Look for a login process in /etc/inittab > > Best regards > > > > > -----Original Message----- > > > From: linux-serial-owner@xxxxxxxxxxxxxxx > > > [mailto:linux-serial-owner@xxxxxxxxxxxxxxx]On Behalf Of Rick Bolen > > > Sent: Thursday, September 18, 2008 2:14 PM > > > To: linux-serial@xxxxxxxxxxxxxxx > > > Subject: serial port being reset at top of every hour? > > > > > > > > > Hello all, > > > > > > I've been trying to chase down an issue for about one month now. > > > > > > Config: > > > Debian Etch (4.04a) w/xfce, kernel 2.6.18-6-686, VIA PC2500E > > > mobo, Moxa > > > Smartio C168H/PCI (rev 01) > > > > > > Symptoms: > > > I run a Perl based home automation software package, > > > Misterhouse (been > > > running it on various versions of Debian since ~'98). It > > > interfaces to > > > numerous serial devices through the mobo's ttyS0 and the Moxa ttyMx > > > ports. It uses the SerialPort.pm PERL module (POSIX) for initializing > > > and utilizing ports. > > > > > > At the top of the hour, some [other] process resets either ttyM0 or > > > ttyS0 (randomly determined at boot?) which causes the home automation > > > software to lose communication to the device. > > > > > > Question: > > > How can I determine what process is resetting the port? Is there any > > > logging available to list PIDs that access a port? ...or a > > > way to attach > > > a debugger to "the system" so I can identify the process? > > > > > > I used strace on the home automation process to verify that it wasn't > > > clobbering itself, but I have no idea what other processes may be > > > "candidates", so I need to watch this from the system level. > > > > > > Thank you, > > > > > > Rick Bolen > > > > > > > > > -- > > > To unsubscribe from this list: send the line "unsubscribe > > > linux-serial" in > > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
