linux-kernel - Re: [GIT PULL] perf changes for v3.8

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: <20121213073056.GA13156@gmail.com>
Date:	Thu, 13 Dec 2012 08:30:56 +0100
From:	Ingo Molnar <mingo@...nel.org>
To:	David Ahern <dsahern@...il.com>
Cc:	Linus Torvalds <torvalds@...ux-foundation.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Arnaldo Carvalho de Melo <acme@...radead.org>,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>,
	Thomas Gleixner <tglx@...utronix.de>,
	Andrew Morton <akpm@...ux-foundation.org>
Subject: Re: [GIT PULL] perf changes for v3.8


* David Ahern <dsahern@...il.com> wrote:

> > But doing it this way was wrong. Switch that "exclude_guest" 
> > attribute around, and admit that "H" was bogus, and that the 
> > right thing to do was to add a "V" flag that sets the 
> > "force_guest" flag instead.
> 
> I understand this is annoying. [...]

It's not annoying, it's outright broken - it's a regression that 
we'll fix.

> [...] Older binaries on newer kernels was the only case I 
> could not fix. [...]

The "only" case?? Old, working binaries are actually our _most_ 
important usecase: it's 99.9% of our current installed base ...

> [...] (I guess a message could be added kernel side to at 
> least give a hint.) But the alternative -- based on code that 
> has existed for some time -- is for older binaries to crash 
> VMs.

That should be fixed differently, by not breaking existing 
working functionality.

Thanks,

	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/