Re: [BUG] Threaded printk breaks early debugging

[Peter Geis]

On Sat, Jun 11, 2022 at 10:57 PM Sergey Senozhatsky
<senozhatsky@xxxxxxxxxxxx> wrote:
>
> On (22/06/10 11:34), Peter Geis wrote:
> > > On 2022-06-10, Peter Geis <pgwipeout@xxxxxxxxx> wrote:
> > > > However I've run into an issue debugging early boot issues. Anything
> > > > that causes the kernel threading system to die (for example here, a
> > > > NPE) causes the boot console to halt before it outputs the error.
> > >
> > > A null pointer exception should trigger a panic, which will cause printk
> > > to enter direct mode for the oops. It should be just as effective as
> > > before introducing the printing kthreads.
> >
> > This might be a side effect of the fact that this is on a low powered
> > arm64 board. I noticed with threading enabled during large bursts the
> > console drops an excessive amount of messages. It's especially
> > apparent during the handover from earlycon to the normal console.
>
> How many CPUs does it have?

Four and all are online when the error occurs.