> I am experimenting with the kernel (CentOSv4.4 x86_64, 2.6.9-42.0.10) > and I have added a number of traces in some relatively sensitive code > in the page cache and some i/o functions. > > I am getting this odd content in the trace log (dmesg), and I cannot > figure out what it is or why it is there. > > 4296757675 pdflush(80): do_writepages: map>ops>wrtpgs ffffffffa0195ff5 > 4296757675 pdflush(80): mpage_writepages w/b index 49728 pages 256000 > <7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7> > <7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7> > <7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7> > <7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7> > <7><7><7><7><7>__bio_add_page: 2x ph 88>=128 || hw 88>=88 || 360448>max > ffffffff802525d8 generic_make_request(bio 000001017c745300) 50729472, 704 > __make_request(q 00000101b9293870, bio 000001017c745300: sdc; 50729600, 704) > ll_new_hw_segment: 70 + 29 > 88 > <7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7> > <7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7> > <7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7> > <7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7><7> > <7><7><7><7>__bio_add_page: 2x ph 88>=128 || hw 88>=88 || 360448>max > ffffffff802525d8 generic_make_request(bio 000001017c745a80) 50730176, 704 > __make_request(q 00000101b9293870, bio 000001017c745a80: sdc; 50730304, 704) > 4296757684 swapper(0): dl_mv2dsp: sdc start 50710368 secs 1408 > > (The lines with the <7>s in them are long - I wrapped them for ease of > reading and to keep the width down somewhat.) > > Any feedback that might illuminate this would be welcome. Please CC > me personally as I am not yet able to subscribe to this list > (apologies).
"<7>" is KERN_DEBUG in <include/linux/kernel.h>, used with printk. Are you using printk in the following forms? printk(KERN_DEBUG "A debug message.\n"); ...or... const char msg_debug[] = KERN_DEBUG "A debug message.\n"; printk(msg_debug); Perhaps you have something looping that's outputting KERN_DEBUG with a null message? Or one of your diagnostic printk statements includes KERN_DEBUG with no actual message? Remember, if you have a string in a variable without a KERN_* prependation, you can do this. printk(KERN_DEBUG "%s\n", debug_message); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/