linux-kernel - Re: [PATCH] Fix booting pentium+ with dodgy TSC

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]

Date:	Sun, 6 Apr 2008 13:22:08 +0200
From:	Ingo Molnar <mingo@...e.hu>
To:	Rusty Russell <rusty@...tcorp.com.au>
Cc:	Linus Torvalds <torvalds@...ux-foundation.org>,
	Andi Kleen <ak@...e.de>, "H. Anvin" <hpa@...or.com>,
	linux-kernel@...r.kernel.org, lguest <lguest@...abs.org>,
	Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [PATCH] Fix booting pentium+ with dodgy TSC

* Rusty Russell <rusty@...tcorp.com.au> wrote:

> Linus please apply.  Almost by definition this patch can't make things 
> worse.

well, while i agree with the patch it could make things worse. In this 
case it can cause code that has been compiled to rely on TSC to 
malfunction. For if sched_clock() was using cpu_has_tsc it could return 
0 all the time, breaking the scheduler without the user having a clear 
idea why it broke. It isnt, and sched_clock() will work fine, but still, 
your "this cant make things worse" statement is not completely correct. 

In any case:

 Acked-by: Ingo Molnar <mingo@...e.hu>

and i've also queued it up into the for-.25 queue of x86.git.

	Ingo
--
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/