NetBSD Problem Report #55694
From www@netbsd.org Sun Oct 4 19:16:00 2020
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for <gnats-bugs@gnats.NetBSD.org>; Sun, 4 Oct 2020 19:16:00 +0000 (UTC)
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Date: Sun, 4 Oct 2020 19:15:59 +0000 (UTC)
From: nia@pkgsrc.org
Reply-To: nia@pkgsrc.org
To: gnats-bugs@NetBSD.org
Subject: "TSC time went backwards" spam on resume on amd64 (regression in -current)
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>Number: 55694
>Category: port-amd64
>Synopsis: "TSC time went backwards" spam on resume on amd64 (regression in -current)
>Confidential: no
>Severity: non-critical
>Priority: medium
>Responsible: port-amd64-maintainer
>State: closed
>Class: sw-bug
>Submitter-Id: net
>Arrival-Date: Sun Oct 04 19:20:00 +0000 2020
>Closed-Date: Fri Sep 20 09:06:22 +0000 2024
>Last-Modified: Fri Sep 20 09:06:22 +0000 2024
>Originator: nia
>Release: NetBSD -current
>Organization:
>Environment:
NetBSD r 9.99.73 NetBSD 9.99.73 (GENERIC) #15: Sun Oct 4 20:17:57 CEST 2020 nia@r:/home/nia/src/sys/arch/amd64/compile/obj/GENERIC amd64
>Description:
After suspending, for several seconds after resume, the console gets spammed with "TSC time went backwards" on amd64. This is very agitating, clutters the console, and doesn't happen on netbsd-9. As a user, I have no idea what to do with this information other than tell the kernel to avoid using TSC.
I can observe this on several different amd64 laptops running -current.
https://i.imgur.com/adpeVld.jpg
>How-To-Repeat:
sysctl -w hw.acpi.sleep.state=3. Wake up. Watch for several seconds as the console is filled with TSC messages.
>Fix:
We should probably not be relying on TSC on anything that is capable of modern power management, since it's unreliable in this case.
Otherwise, the message should only be printed once.
>Release-Note:
>Audit-Trail:
State-Changed-From-To: open->feedback
State-Changed-By: riastradh@NetBSD.org
State-Changed-When: Mon, 08 Jul 2024 17:31:20 +0000
State-Changed-Why:
Probably fixed in:
https://mail-index.netbsd.org/source-changes/2021/06/01/msg129933.html
Can you confirm?
State-Changed-From-To: feedback->closed
State-Changed-By: nia@NetBSD.org
State-Changed-When: Fri, 20 Sep 2024 09:06:22 +0000
State-Changed-Why:
fixed
>Unformatted:
(Contact us)
$NetBSD: query-full-pr,v 1.51 2026/08/10 02:28:17 riastradh Exp $
$NetBSD: gnats_config.sh,v 1.10 2026/05/13 22:00:09 riastradh Exp $
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