linux-kernel - Re: [PATCH 07/14] mce3: pass mce info to EDAC for decoding

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: <4A64D0F2.7050009@zytor.com>
Date:	Mon, 20 Jul 2009 13:17:54 -0700
From:	"H. Peter Anvin" <hpa@...or.com>
To:	Andi Kleen <andi@...stfloor.org>
CC:	Doug Thompson <norsk5@...oo.com>,
	Borislav Petkov <borislav.petkov@....com>, mingo@...e.hu,
	tglx@...utronix.de, aris@...hat.com, linux-kernel@...r.kernel.org,
	x86@...nel.org
Subject: Re: [PATCH 07/14] mce3: pass mce info to EDAC for decoding

Andi Kleen wrote:
>> The goal is to have a default handler within the kernel and a more specific handler in a module after it has loaded. Using the weak symbol as a mechanism to do that. I haven't used that, so I don't know if it works.
> 
> weak symbols don't work over kernel modules.
> 

For modules, you typically have to have a callback to update an internal
function pointer.  If you think about it, it's pretty obvious -- a weak
symbol changes the behavior at link time, but it's still a static call.
 If you want modules to change the behavior, you're talking about a
*dynamic* change -- the call will point to different things at different
points in time -- so you need another mechanism, i.e. function pointers.

	-hpa

--
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/