Messages in this thread | | | From | Sergey Senozhatsky <> | Date | Fri, 7 Sep 2018 23:52:21 +0900 | Subject | Re: [PATCH] printk/tracing: Do not trace printk_nmi_enter() |
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On (09/07/18 16:03), Peter Zijlstra wrote: > > > > I would even argue that placing printk_nmi_enter() between > > lockdep_off() and ftrace_nmi_enter() is wrong because if in the future > > printk_nmi_enter() were to do any ftrace tracing, it wont be caught, as > > it was by having it before lockdep_off(). > > > > printk_nmi_enter() should not muck with IRQ state, nor should it do any > > ftrace tracing. Since ftrace mucks with IRQ state when it gets enabled > > or disabled, it will screw up lockdep, and lockdep will complain. That > > way we can use lockdep not being off to catch this bug. > > The very bestest solution is to rm -rf printk ;-)
Talented, capable and tremendously clever people had spent decades on making printk what it is today. I feel responsible for respecting that effort and, thus, my vote would be to keep printk around for a while. ... we also support !CONFIG_PRINTK builds ;)
-ss
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