From: Ondrej Zary <linux@rainbow-software.org>
To: Len Brown <lenb@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>,
Stephen Rothwell <sfr@canb.auug.org.au>,
x86@kernel.org, linux-pm@lists.linux-foundation.org,
linux-kernel@vger.kernel.org,
Linus Torvalds <torvalds@linux-foundation.org>,
Thomas Gleixner <tglx@linutronix.de>,
"H. Peter Anvin" <hpa@zytor.com>,
Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] x86 APM: delete Linux kernel APM support
Date: Sun, 27 Mar 2011 23:40:31 +0200 [thread overview]
Message-ID: <201103272340.42748.linux@rainbow-software.org> (raw)
In-Reply-To: <alpine.LFD.2.02.1103260036300.28928@x980>
On Saturday 26 March 2011 06:01:38 Len Brown wrote:
> > Regardless of removal, i'd suggest a "this code is not supported" kind of
> > WARN() message to the APM code today, into .39 - to see whether it pops
> > up anywhere - and mark it for -stable as well.
>
> Okay, can do.
>
> > .42 removal might be too fast, considering the typical release schedule
> > of Linux distributions. And i'm still doubting the removal itself: we are
> > adding lots of special-purpose subarch drivers to arch/x86/ as we speak
> > (the embedded mess coming to x86) - which drivers will be tomorrow's APM
> > code. On what grounds do we treat APM support differently?
> >
> > Our general compatibility with old hardware is an *asset* that we should
> > value.
>
> My guess is that the customers have died off,
> and so the code is no longer an asset, but a maintenance liability.
>
> If there is a buzzing community of people running 2011
> linux kernels on their ancient laptops in APM mode,
> then the APM maintainer would probably know about them.
>
> Personally, my oldest usable laptop is a T23 from March 2002.
> It supports APM and ACPI (it shipped with Win2K).
> Linux works well on it in ACPI mode, but doesn't even boot in APM mode.
> If anybody was really using the latest kernel in APM mode,
> I suspect this laptop would boot...
>
> Is there somebody on LKML that has a older laptop than me
> and is able to get it to boot in APM mode? I'd be astonished
> if there was not. Are they willing to regularly test changes
> to the upstream kernel to make sure that APM still works?
> If yes, where have they been for the last 5 years?
I just tested 2.6.38-rc4 on a desktop board and it works (power off at least).
If using Grub2, linux16 command must be used instead of linux in grub.cfg
(otherwise loading apm module will fail with "apm: BIOS not found").
I also have some working laptops with APM but haven't tried recent kernels
yet.
> I suspect when there is nobody using the latest kernel on mrst,
> then the latest kernel can delete support for mrst, and nobody will care.
> Like APM, it will probably undergo "maintenance without testing",
> aka bit rot, for a period before that happens.
--
Ondrej Zary
next prev parent reply other threads:[~2011-03-27 21:40 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <alpine.LFD.2.02.1103232321070.3848@x980>
[not found] ` <20110324154505.934a56a0.sfr@canb.auug.org.au>
2011-03-24 7:39 ` [PATCH] APM: delete APM in Linux-2.6.40 Len Brown
2011-03-24 8:16 ` [PATCH] x86 APM: delete Linux kernel APM support Len Brown
2011-03-24 8:31 ` [PATCH] x86 APM: delete Linux kernel APM support (v2) Len Brown
2011-03-24 16:01 ` Andi Kleen
2011-03-24 8:39 ` [PATCH] x86 APM: delete Linux kernel APM support Ingo Molnar
2011-03-24 23:49 ` Len Brown
2011-03-25 11:30 ` Ingo Molnar
2011-03-25 12:38 ` Ingo Molnar
2011-03-25 12:41 ` Ingo Molnar
2011-03-25 22:33 ` Rafael J. Wysocki
2011-03-26 4:35 ` Len Brown
2011-04-08 6:25 ` Pavel Machek
2011-04-08 20:55 ` H. Peter Anvin
2011-04-11 13:05 ` Pavel Machek
2011-04-11 18:19 ` H. Peter Anvin
2011-04-13 13:30 ` Pavel Machek
2011-03-26 5:01 ` Len Brown
2011-03-26 9:31 ` Ingo Molnar
2011-03-27 21:40 ` Ondrej Zary [this message]
2011-03-28 4:51 ` Ingo Molnar
2011-03-28 5:43 ` H. Peter Anvin
2011-03-28 12:57 ` H. Peter Anvin
2011-03-28 5:18 ` Ingo Molnar
2011-03-25 15:41 ` Calvin Walton
2011-03-24 8:18 ` [PATCH] APM: delete APM in Linux-2.6.40 Stephen Rothwell
2011-03-24 8:38 ` Alexander Stein
2011-03-24 10:21 ` Henrique de Moraes Holschuh
2011-03-24 23:05 ` Len Brown
2011-03-25 1:07 ` Henrique de Moraes Holschuh
2011-03-25 1:34 ` Len Brown
2011-04-04 16:44 ` Pavel Machek
2011-04-04 20:18 ` Len Brown
2011-03-24 12:15 ` Ondrej Zary
2011-03-24 23:29 ` Len Brown
2011-03-25 8:07 ` Ondrej Zary
2011-03-26 5:09 ` Len Brown
2011-04-02 21:40 ` Yuhong Bao
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