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From: John Ogness <john.ogness@linutronix.de>
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To: paulmck@kernel.org, Tejun Heo <tj@kernel.org>, Lai Jiangshan
 <jiangshanlai@gmail.com>, Petr Mladek <pmladek@suse.com>, Steven Rostedt
 <rostedt@goodmis.org>, Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>, linux-kernel@vger.kernel.org,
 rcu@vger.kernel.org
Subject: Re: [BUG] workqueues and printk not playing nice since next-20240130
In-Reply-To: <410d6a87-bf34-457e-b714-1e6149d48532@paulmck-laptop>
References: <410d6a87-bf34-457e-b714-1e6149d48532@paulmck-laptop>
Date: Fri, 02 Feb 2024 15:18:48 +0106
Message-ID: <87le83ara7.fsf@jogness.linutronix.de>
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On 2024-02-02, "Paul E. McKenney" <paulmck@kernel.org> wrote:
> So the system really did boot and is running just fine.  It is just that
> there is no console output.  Details, details!
>
> Is there anything I can do to some combination of workqueues and printk
> to help debug this?

The printk ringbuffer contents would certainly be interesting.

If you build the GDB scripts (CONFIG_GDB_SCRIPTS) then you will have:

(gdb) lx-dmesg

As an alternative, you could copy the contents of
Documentation/admin-guide/kdump/gdbmacros.txt into your .gdbinit and
then will have:

(gdb) dmesg

There may be some hints in the kernel log as to why there is no console
output.

John