On 2020/05/13 19:49, Michal Hocko wrote: > On Wed 13-05-20 12:04:13, Petr Mladek wrote: >> What is so special about OOM dump task so that it would deserve such >> complications? > > Nothing really. Except for the potential amount of the output.
"echo t > /proc/sysrq-trigger" from userspace program is another example. > But as > you've said there are two ways around that. Disable this output if you > do not need it or make it a lower loglevel. Disable this output for syslog is not acceptable for me, but disable this output for consoles is preferable for me. > I simply cannot tell whether somebody considers > dump_tasks an important information to be printed on consoles. I don't think dump_tasks() is important information to be printed on consoles. But since somebody might think dump_tasks() is important information to be printed on consoles, I suggest switching KERN_NO_CONSOLES using e.g. sysctl. > > If there is any need to control which messages should be routed to which > backend then the proper solution would be to filter messages per log > level per backend. Possible backends will be "zero or more than zero" consoles + "zero or one" syslog, and KERN_NO_CONSOLES is a method for force selecting "zero" console backend. > But I have no idea how feasible this is for the > existing infrastructure - or maybe it already exists... There is per-console loglevel proposal (which allows selecting "some" console backends). But it is based on KERN_$LOGLEVEL which is too rough-grained.
