linux-kernel - Re: [PATCH v2] MIPS64: Support of at least 48 bits of SEGBITS

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

Message-ID: <alpine.LFD.2.11.1505160305100.4923@eddie.linux-mips.org>
Date:	Sat, 16 May 2015 03:11:01 +0100 (BST)
From:	"Maciej W. Rozycki" <macro@...ux-mips.org>
To:	Leonid Yegoshin <Leonid.Yegoshin@...tec.com>
cc:	David Daney <ddaney.cavm@...il.com>,
	"aleksey.makarov@...iga.com" <aleksey.makarov@...iga.com>,
	James Hogan <James.Hogan@...tec.com>,
	Paul Burton <Paul.Burton@...tec.com>,
	"david.daney@...ium.com" <david.daney@...ium.com>,
	"peterz@...radead.org" <peterz@...radead.org>,
	"linux-mips@...ux-mips.org" <linux-mips@...ux-mips.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"ralf@...ux-mips.org" <ralf@...ux-mips.org>,
	"davidlohr@...com" <davidlohr@...com>,
	"kirill@...temov.name" <kirill@...temov.name>,
	"akpm@...ux-foundation.org" <akpm@...ux-foundation.org>,
	"mingo@...nel.org" <mingo@...nel.org>
Subject: Re: [PATCH v2] MIPS64: Support of at least 48 bits of SEGBITS

On Fri, 15 May 2015, Leonid Yegoshin wrote:

> > Many processors support larger VA space than is utilized by the kernel.
> >    A choice was made to reduce the size of the VA space in order to
> > reduce TLB handling overhead.
> >
> > If the true reason for the patch is to enable larger VA space, say that.
> >    But is it really required by those processors you mention?  I doubt it.
> 
> Well, I was not aware about many processors capability, I can't find this kind
> of note anywhere.

 The R10000 and friends all have a 44-bit virtual address space, so this 
is no news to Linux.  This is noted in <asm/processor.h> right above the 
change you made there.

  Maciej
--
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/