Re: [BUG] workqueues and printk not playing nice since next-20240130

From: Paul E. McKenney
Date: Fri Feb 02 2024 - 10:58:15 EST


On Fri, Feb 02, 2024 at 03:18:48PM +0106, John Ogness wrote:
> On 2024-02-02, "Paul E. McKenney" <paulmck@xxxxxxxxxx> 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

This says no such command even though I do have CONFIG_GDB_SCRIPTS=y
in my .config.

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

This one hangs.

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

On the other hand, next-20240202 doesn't show the problem. No idea
what might have changed. :-/

Thanx, Paul