linux-kernel - Re: [PATCH, resend] x86/PCI: don't export a _

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <AANLkTi=SR-HsBuOA0V6GPtD4wY+s663_6TT9aJVVjjrK@mail.gmail.com>
Date:	Thu, 17 Feb 2011 15:12:45 -0800
From:	Yinghai Lu <yinghai@...nel.org>
To:	Mauro Carvalho Chehab <mchehab@...hat.com>
Cc:	Jan Beulich <JBeulich@...ell.com>, mingo@...e.hu,
	tglx@...utronix.de, hpa@...or.com, arozansk@...hat.com,
	Michal Marek <mmarek@...e.cz>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH, resend] x86/PCI: don't export a __devinit function

On Thu, Feb 17, 2011 at 10:12 AM, Mauro Carvalho Chehab
<mchehab@...hat.com> wrote:
> Em 17-02-2011 14:08, Jan Beulich escreveu:
>> Exporting a __devinit function (pcibios_scan_specific_bus()) isn't
>> correct. (Michal, any reason why modpost only warns about exported
>> __init functions?) Short of being able to think of a better solution,
>> and short of making the whole call tree (reaching into the arch-
>> independent part of the PCI subsystem) non-__devinit, export the
>> symbol only when HOTPLUG is enabled (which is always the case for non-
>> expert configurations), use section mismatch avoidance annotations for
>> that case (knowing that __devinit functions will not be discarded),
>> and mark the symbol __devinit only in the !HOTPLUG case.
>>
>> Consequently, EDAC_I7CORE (consuming the export) then has to depend on
>> HOTPLUG.
>
> Having the entire i7core_edac driver depending on HOTPLUG, just because
> a few BIOSes want to hide the non-core PCI devices doesn't seem nice.
> One alternative would be to enclose the code that needs this function
> with #ifdef CONFIG_HOTPLUG.
>
>> A fundamental question of course if whether this driver has
>> to use that function in the first place (i.e. whether it wouldn't be
>> better to just remove the export) - the problem it tries to address
>> happens on other systems too, but the PCI bus the devices in question
>> live on isn't necessarily bus 255. For the affected system I have, the
>> alternative approach is to set pcibios_last_bus from __pci_mmcfg_init()
>> based on the highest bus number on segment 0 being covered by MCFG.
>
> I received a few days ago a report that some BIOSes that hide those
> PCI devices also use a different address for the last bus (0x3f, instead
> of 0xff). So, it seems that the better would be to use an alternative
> way to retrieve the last bus.

just append "pci=lastbus=255" will get all those devices.

Yinghai
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/