linux-kernel - Re: [PATCH-WIP 01/13] xen/arm: use r12 to pass the hypercall number to the hypervisor

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: <1330423635.31269.40.camel@zakaz.uk.xensource.com>
Date:	Tue, 28 Feb 2012 10:07:15 +0000
From:	Ian Campbell <Ian.Campbell@...rix.com>
To:	Dave Martin <dave.martin@...aro.org>
CC:	Stefano Stabellini <Stefano.Stabellini@...citrix.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"xen-devel@...ts.xensource.com" <xen-devel@...ts.xensource.com>,
	"linaro-dev@...ts.linaro.org" <linaro-dev@...ts.linaro.org>,
	"arnd@...db.de" <arnd@...db.de>,
	"catalin.marinas@....com" <catalin.marinas@....com>,
	David Vrabel <david.vrabel@...rix.com>,
	"kvm@...r.kernel.org" <kvm@...r.kernel.org>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>
Subject: Re: [PATCH-WIP 01/13] xen/arm: use r12 to pass the hypercall number
 to the hypervisor

On Tue, 2012-02-28 at 09:46 +0000, Dave Martin wrote:
> On Mon, Feb 27, 2012 at 07:48:45PM +0000, Ian Campbell wrote:
> > Given that Stefano is proposing to make the ISS a (per-hypervisor)
> > constant we could consider just defining the Thumb and non-Thumb
> > constants instead of doing all the construction with the __HVC_IMM stuff
> > -- that would remove a big bit of the macroization.
> 
> It's not quite as simple as that -- emitting instructions using data
> directives is not endianness safe, and even in the cases where .long gives
> the right result for ARM, it gives the wrong result for 32-bit Thumb
> instructions if the opcode is given in human-readable order.

Urk, yes,..

> I was trying to solve the same problem for the kvm guys with some global
> macros -- I'm aiming to get a patch posted soon, so I'll make sure
> you're on CC.

Awesome, thanks!

Ian.

--
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/