linux-kernel - Re: [PATCH] mm: fix page_mkclean_one (was: 2.6.19 file content corruption on ext3)

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 21 Dec 2006 10:26:15 +0100
From:	Martin Schwidefsky <schwidefsky@...ibm.com>
To:	Peter Zijlstra <a.p.zijlstra@...llo.nl>
Cc:	Linus Torvalds <torvalds@...l.org>,
	Martin Michlmayr <tbm@...ius.com>,
	Hugh Dickins <hugh@...itas.com>,
	Nick Piggin <nickpiggin@...oo.com.au>,
	Arjan van de Ven <arjan@...radead.org>,
	Andrei Popa <andrei.popa@...eo.ro>,
	Andrew Morton <akpm@...l.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Florian Weimer <fw@...eb.enyo.de>,
	Marc Haber <mh+linux-kernel@...schlus.de>,
	Heiko Carstens <heiko.carstens@...ibm.com>,
	Arnd Bergmann <arnd.bergmann@...ibm.com>,
	gordonfarquharson@...il.com
Subject: Re: [PATCH] mm: fix page_mkclean_one (was: 2.6.19 file content
	corruption on ext3)

On Thu, 2006-12-21 at 10:20 +0100, Peter Zijlstra wrote:
> > Now you are flushing the tlb twice. ptep_clear_flush clears the pte and
> > flushes the tlb, ptep_establish sets the new pte and flushes the tlb.
> > Not good. Use set_pte_at instead of the ptep_establish.
> 
> Yeah, sorry, I already noticed and corrected that :-|
> 
> Also, I'm dubious about the while thing and stuck a WARN_ON(ret) thing
> at the beginning of the loop. flush_tlb_page() does IPI the other cpus
> to flush their tlb too, so there should not be a SMP race, Arjan?

The while loop is protected by the pte lock and flush_tlb_page has to
remove the tlbs on all cpus. So yes, I think the while loop is not
necessary.

-- 
blue skies,
  Martin.

Martin Schwidefsky
Linux for zSeries Development & Services
IBM Deutschland Entwicklung GmbH

"Reality continues to ruin my life." - Calvin.


-
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/