Received-SPF: pass (google.com: domain of linux-kernel+bounces-13183-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45e3:2400::1 as permitted sender) client-ip=2604:1380:45e3:2400::1;
Date: Fri, 29 Dec 2023 11:28:23 -0600
From: "Theodore Ts'o" <tytso@mit.edu>
To: Chris Rankin <rankincj@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>, LKML <linux-kernel@vger.kernel.org>,
        netdev@vger.kernel.org
Subject: Re: Does Linux still support UP?
Message-ID: <20231229172823.GC148343@mit.edu>
References: <CAK2bqVKCdaD6-PZi6gXhf=9CiKGhxQM_UHyKV_onzDPnhbAmvw@mail.gmail.com>
 <ZY7omD5OBLUg6pyx@duo.ucw.cz>
 <CAK2bqVLBZvU2fVfY4bkFrU=4X+W4O3f5pbTdeQjMW=W2sGWpeQ@mail.gmail.com>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAK2bqVLBZvU2fVfY4bkFrU=4X+W4O3f5pbTdeQjMW=W2sGWpeQ@mail.gmail.com>

On Fri, Dec 29, 2023 at 04:03:56PM +0000, Chris Rankin wrote:
> 
> I have already attached as much information as I am *ever* likely to
> be able to extract about this problem to the Bugzilla ticket.

In addition to doing a bisection, something else you might want to
try, since in the bugzilla you have hypothesized that it might be a
bug in the e100 driver, is to try building a kernel without the driver
configured, and see if that makes the kernel not hang.  If it does,
then it's likely that the problem is either in the e100 driver, or
maybe somewhere in the networking stack --- although in that case it's
more likely someone else would have noticed.

Something else you might try is to connect up a serial console, so you
can get the full output from sysrq output.  The other advantage of
using a serial console is people are much more likely to scan a text
file with the consoles, as opposed to downloading and trying to make
sense of the screen snapshots.  (BTW, was the flash enabled on your
cell phone?  The bright white spot in the middle of the screen makes
it very hard to read.)

I'd also try sysrq-l (show backtrace for all active CPU's), so you can
see where the kernel is actually hanging.

For better or for worse, support for old hardware is a volunteer
effort, so owners of the said old hardware need to do a bunch of the
leg work.  Or if you can have a paid support contract, maybe you can
pay someone to gather the detail, but when you say "is feature X
supported" in an open source project, that has a different meaning
from a commercial software product.

						- Ted