linux-kernel - Re: [RFC][PATCH 4/6] arm, mm: Convert arm to generic tlb

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] [day] [month] [year] [list]

Message-ID: <20120521094709.6036d868@de.ibm.com>
Date:	Mon, 21 May 2012 09:47:09 +0200
From:	Martin Schwidefsky <schwidefsky@...ibm.com>
To:	Peter Zijlstra <a.p.zijlstra@...llo.nl>
Cc:	Catalin Marinas <catalin.marinas@....com>,
	Russell King <rmk@....linux.org.uk>,
	Paul Mundt <lethal@...ux-sh.org>,
	Andrea Arcangeli <aarcange@...hat.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Rik van Riel <riel@...hat.com>, Ingo Molnar <mingo@...e.hu>,
	"akpm@...ux-foundation.org" <akpm@...ux-foundation.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-arch@...r.kernel.org" <linux-arch@...r.kernel.org>,
	"linux-mm@...ck.org" <linux-mm@...ck.org>,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>,
	David Miller <davem@...emloft.net>,
	Hugh Dickins <hugh.dickins@...cali.co.uk>,
	Mel Gorman <mel@....ul.ie>, Nick Piggin <npiggin@...nel.dk>,
	Chris Metcalf <cmetcalf@...era.com>
Subject: Re: [RFC][PATCH 4/6] arm, mm: Convert arm to generic tlb

On Thu, 17 May 2012 18:24:44 +0200
Peter Zijlstra <a.p.zijlstra@...llo.nl> wrote:

> On Thu, 2012-05-17 at 17:00 +0100, Catalin Marinas wrote:
> 
> > BTW, looking at your tlb-unify branch, does tlb_remove_table() call
> > tlb_flush/tlb_flush_mmu before freeing the tables?  I can only see
> > tlb_remove_page() doing this. On ARM, even UP, we need the TLB flushing
> > after clearing the pmd and before freeing the pte page table (and
> > ideally doing it less often than at every pte_free_tlb() call).
> 
> No I don't think it does, so far the only archs using the RCU stuff are
> ppc,sparc and s390 and none of those needed that (Xen might join them
> soon though). But I will have to look and consider this more carefully.
> I 'lost' most of the ppc/sparc/s390 details from memory to say this with
> any certainty.
 
s390 needs a TLB flush for the pgd, pud and pmd tables. See git commit
cd94154cc6a28dd9dc271042c1a59c08d26da886 for the sad details.

-- 
blue skies,
   Martin.

"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/