Date: Thu, 02 Aug 2007 17:18:10 -0700
From: Yinghai Lu <Yinghai.Lu@Sun.COM>
Subject: Re: REGRESSION: serial_cs broken by 8250 changes
In-reply-to: <20070802163547.39f41af1.akpm@linux-foundation.org>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Daniel Ritz <daniel.ritz-ml@swissonline.ch>,
       Linus Torvalds <torvalds@linux-foundation.org>,
       Bjorn Helgaas <bjorn.helgaas@hp.com>, linux-kernel@vger.kernel.org
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References: <200708030106.33917.daniel.ritz-ml@swissonline.ch>
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Andrew Morton wrote:
> On Thu, 02 Aug 2007 16:24:42 -0700
> Yinghai Lu <Yinghai.Lu@Sun.COM> wrote:
> 
>> Daniel Ritz wrote:
>>> commit 18a8bd949d6adb311ea816125ff65050df1f3f6e breaks serial_cs badly
>>> with an oops, completely killing PCMCIA.
>>>
>>> register_console() now calls console->early_setup(). which in case of
>>> 8250.c (the only user anyway) is serial8250_console_early_setup()
>>> which is __init, calling 8250_early.c:serial8250_find_port_for_earlycon()
>>> which is __init as well. boom.
>>>
>>> the changelog mentions SERIAL_PORT_DFNS removal which happens to be
>>> commit 7e92b4fc345f5b6f57585fbe5ffdb0f24d7c9b26. but this got reverted
>>> by commit 57d4810ea0d9ca58a7bcc1336607f0cede0a2abf. so i'd suggest to
>>> just revert the 8250 changes as well.
>>>
>>> rgds
>>> -daniel
>> Is there any flag or sign that init code has been released?
> 
> Nope.
> 
>> We could use that to prevent init code to be called after code is freed.
> 
> If we can omit a function call without breaking anything then we shouldn't
> have been calling that function at all ;)
> 
> It sounds like making serial8250_console_early_setup() and
> serial8250_find_port_for_earlycon() non-__init will fix this.
> 

yes, together update_console_cmdline in kernel/printk.c

Daniel,
can you test that in your setup?

Thanks

Yinghai Lu
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