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Reverting this on top of -next fixes the issue. Previously with >> V5 I did not see a boot issue only an issue in suspend. So far I have not >> had chance to dig any further. > > Interesting. > > Another clue, mentioned in the v9 thread [1], is that the boot > regression does not happen with v11 when "keep_bootcon" option > is used. > > The "keep_bootcon" option causes that the boot console driver stays > registered even when the full featured driver gets registered > later. > > The most important effect is that the printk kthreads can't > be used as long as any boot console driver is registered. > All drivers need to be called in the legacy loop in this case. > There are two reasons for this: > > 1. Boot console drivers are synchronized only by > the legacy console_lock (console_sem). port->lock > is available only for the full featured driver. > > 2. There is no easy way to match boot console and > full featured console drivers working on the same > HW. > > So, the regression seems to happen when the printk kthreads > start being used. > > Jon, could you please share the full log when "keep_bootcon" > is used? Yes absolutely. You can find the boot log here [0]. So far nothing really stands out to me but let me know if you see anything. Jon [0] https://pastebin.com/FhQVSqfy -- nvpublic