linux-kernel - Re: [patch 04/41] cpu ops: Core piece for generic atomic per cpu operations

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: <200806171024.40662.rusty@rustcorp.com.au>
Date:	Tue, 17 Jun 2008 10:24:40 +1000
From:	Rusty Russell <rusty@...tcorp.com.au>
To:	Christoph Lameter <clameter@....com>
Cc:	Nick Piggin <nickpiggin@...oo.com.au>,
	Martin Peschke <mp3@...ibm.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	linux-arch@...r.kernel.org, linux-kernel@...r.kernel.org,
	David Miller <davem@...emloft.net>,
	Eric Dumazet <dada1@...mosbay.com>,
	Peter Zijlstra <peterz@...radead.org>,
	Mike Travis <travis@....com>
Subject: Re: [patch 04/41] cpu ops: Core piece for generic atomic per cpu operations

On Tuesday 17 June 2008 00:52:08 Christoph Lameter wrote:
> On Sun, 15 Jun 2008, Rusty Russell wrote:
> > > 3. Some hooks for arches to override particular behavior as needed.
> > >    F.e. IA64 allocates percpu structures in a special way. x86_64
> > >    needs to do some tricks for the pda etc etc.
> >
> > IA64 is going to need some work, since dynamic percpu addresses won't be
> > able to use their pinned TLB trick to get the local version.
>
> The ia64 hook could simply return the address of percpu area that
> was reserved when the per node memory layout was generated (which happens
> very early during node bootstrap).

Apologies, this time I read the code.  I thought IA64 used the pinned TLB area 
to access per-cpu vars under some circumstances, but they only do that via an 
arch-specific macro.

So creating new congruent mappings to expand the percpu area(s) is our main 
concern now?

Rusty.
--
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/