Hi, What about ftrace ? Documentation/trace/ftrace.txt Thanks Lucas On Tue, Nov 26, 2019 at 8:08 PM aleave <aleave@xxxxxxxxxxxxxx> wrote: > > Hi everyone, > > I'm modifying kernel code and running into system dead-lock issues. I have printk statements to try to retrieve info about the freeze after I do a hard shutdown, but printk is asynchronous so /var/log/kern.log only shows NULL character gibberish instead (^@^@^@^@). Is there a way to make printk synchronous? I have looked at people using printk_sync and printk.synchronous variables as recently as 2017, but I don't see any reference to these anymore in the kernel version I have (5.4). > > Thanks for the help. > > > _______________________________________________ > Kernelnewbies mailing list > Kernelnewbies@xxxxxxxxxxxxxxxxx > https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies