Hello, Steven. On Tue, Jan 23, 2018 at 04:00:54PM -0500, Steven Rostedt wrote: > On Tue, 23 Jan 2018 12:57:06 -0800 > Tejun Heo <[email protected]> wrote: > > > Yeah, it's ridiculous how often printk ends up escalating otherwise > > recoverable situations into system crashes. I don't know what the > > right answer is. For spurious NMI hardlockups, maybe auditing debug > > paths and adding touch_nmi_watchdog() would be enough but that also is > > a pretty leaky approach. > > What about if every printk were to touch NMI watchdog? > > NMI watchdog is really there for when the system locks up. If the > system is locked up doing printk, at least we see what is happening, > and not a total freeze.
Yeah, that would definitely be a solution. The downside is that when the system completely locks up from printk storm while holding critical locks (say, tasklist_lock), the watchdog won't be able to reset the system. I guess the judgement would depend on what one expects of the NMI watchdog, but I personally would be happier with printk touching NMI automatically. Thanks. -- tejun
