linux-kernel - Re: [PATCH 3/3] x86, extable: Handle early exceptions

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: <4F909B56.60001@zytor.com>
Date:	Thu, 19 Apr 2012 16:10:14 -0700
From:	"H. Peter Anvin" <hpa@...or.com>
To:	Linus Torvalds <torvalds@...ux-foundation.org>
CC:	Tony Luck <tony.luck@...il.com>,
	David Daney <ddaney.cavm@...il.com>,
	Borislav Petkov <bp@...64.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Ingo Molnar <mingo@...nel.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	David Daney <ddaney@...iumnetworks.com>
Subject: Re: [PATCH 3/3] x86, extable: Handle early exceptions

On 04/19/2012 03:58 PM, Linus Torvalds wrote:
> 
> In fact, doing an "objdump" on the few modules I have, I didn't find a
> *single* exception table entry. Maybe I did something wrong? Isn't it
> the __ex_table in modules too?
> 

It is, but I suspect a lot of modules don't end up with any exception
table entries, as the common forms of user space access are out of line.

I suspect that just finding the module we're in or not in before
searching its ex_table is probably good enough, but a global hash would
be better.  That being said, some distros are complaining about the
amount of time it takes to load modules on boot...

	-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/