linux-kernel - Re: -tip tree resume fail, bisect to 5bd5a45(x86: Add NX protection for kernel data)

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: <20101123235527.54293b59@mat-laptop>
Date:	Tue, 23 Nov 2010 23:55:27 +0100
From:	mat <castet.matthieu@...e.fr>
To:	Andi Kleen <andi@...stfloor.org>
Cc:	Peter Zijlstra <peterz@...radead.org>,
	Lin Ming <ming.m.lin@...el.com>,
	Siarhei Liakh <sliakh.lkml@...il.com>,
	Xuxian Jiang <jiang@...ncsu.edu>, Ingo Molnar <mingo@...e.hu>,
	Arjan van de Ven <arjan@...radead.org>,
	lkml <linux-kernel@...r.kernel.org>, tglx <tglx@...utronix.de>
Subject: Re: -tip tree resume fail, bisect to 5bd5a45(x86: Add NX protection
 for kernel data)

Le Mon, 22 Nov 2010 17:42:47 +0100,
Andi Kleen <andi@...stfloor.org> a écrit :

> > That seems to be a S3 specific code path, that won't fix anything.
> > Simply do:
> > 
> > echo 0 > /sys/devices/system/cpu/cpu1/online;
> > echo 1 > /sys/devices/system/cpu/cpu1/online;
> > 
> > and your machine will explode..
> 
> The SMP startup trampoline is copied I believe
> and only executed in real mode without page tables.
> 
> So it's perhaps not the trampoline, but the early startup 
> code that ends up being broken.
yes :
acpi wakeup code and smp trampoline are copied in low memory (first
1MB).

So they can't end up int the kernel data mapping ?

So it should something else.

I will try to investigate on this.

Matthieu
--
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/