IMO, I believe if you module is using/hanging all processors it's impossible to kernel use any to print stuffs. What about try Sysrq [1] ? I used it once in a power system plus xmon, but I'll be honest not sure how it works on x86. https://www.kernel.org/doc/Documentation/sysrq.txt On Fri, Aug 21, 2015 at 8:06 AM, Salam Farhat <salalimo@xxxxxxxxx> wrote: > Hi, > > I am not sure if this is the place to ask, if so please let me know where to > do so. > > I am using a kernel module that I modified slightly to work on my current > kernel version. It is running on a virtual machine and on a heavy load it > goes into an infinite loop and freezes the system. I can tell that the > virtual machine is using 100% of its assigned cpu. There are print > statements almost everywhere in the module, but after a few seconds none get > printed. > > > > The kernel has the following options already enabled: > CONFIG_DETECT_SOFTLOCKUP and > > CONFIG_DETECT_HUNG_TASK. To my understanding the kernel is supposed to print > the stack trace when a hung task is detected, however, nothing gets printed > in kern.log. I am not sure if this is the place where the kernel would dump > the stack or if the print process is affected by the hang since the print > statements in the module are not being printed as well. > > > > I would like to know how to debug this issue. Any help is appreciated. > > > > Thank you. > > > > > > > _______________________________________________ > Kernelnewbies mailing list > Kernelnewbies@xxxxxxxxxxxxxxxxx > http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies > -- ---------------------------------------------- Leônidas S. Barbosa (Kirotawa) blog: corecode.wordpress.com _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
