From: Andrew Cooper <andrew.cooper3@citrix.com>
To: xen-devel <xen-devel@lists.xenproject.org>
Cc: "Jan Beulich" <jbeulich@suse.com>,
"Roger Pau Monné" <roger.pau@citrix.com>,
"Denis Mukhin" <dmkhn@proton.me>
Subject: lost serial characters on boot
Date: Fri, 17 Oct 2025 18:09:54 +0100 [thread overview]
Message-ID: <bdead1be-cd8f-4cca-ae70-e9744ae8b556@citrix.com> (raw)
Hi,
I think we've got a bug with the serial console. I'm reliably loosing a
small part of the boot message. e.g.:
(XEN) Latest ChangeSet: Fri Oct 17 17:24:59 2025 git:5e79cfcd2100
(XEN) build-id: d1536ff6698b3e3ba307d551abf
Family 25 (0x19 Stepping 1 (raw 00a00f11)
(XEN) BSP microcode revision: 0x0a001137
whereas from xl dmesg after the system boots, we see things correctly:
(XEN) Latest ChangeSet: Fri Oct 17 17:24:59 2025 git:5e79cfcd2100
(XEN) build-id: d1536ff6698b3b8968e883fc39e3ba307d551abf
(XEN) CPU Vendor: AMD, Family 25 (0x19), Model 1 (0x1), Stepping 1 (raw
00a00f11)
(XEN) BSP microcode revision: 0x0a001137
The lost bit of text differs even when rebooting the same Xen binary,
but it's always around this area, very early on boot.
I've been seeing this for a little while, but one of my common dev
machines is showing it fairly reliably at the moment.
Checking a transcript of the terminal, we're missing characters, rather
than having additional control characters causing the corruption.
I suppose I need to stare at console_init_preirq() some more, but if
anyone has ideas, I'm all ears.
~Andrew
next reply other threads:[~2025-10-17 17:10 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-10-17 17:09 Andrew Cooper [this message]
2025-10-18 9:35 ` lost serial characters on boot Frediano Ziglio
2025-10-18 18:42 ` Frediano Ziglio
2025-10-20 6:26 ` Frediano Ziglio
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