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]
Date:	Fri, 15 Apr 2016 20:48:05 +0200
From:	Arnd Bergmann <arnd@...db.de>
To:	Masahiro Yamada <yamada.masahiro@...ionext.com>
Cc:	Mark Rutland <mark.rutland@....com>, arm@...nel.org,
	devicetree@...r.kernel.org, Kumar Gala <galak@...eaurora.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Ian Campbell <ijc+devicetree@...lion.org.uk>,
	Rob Herring <robh+dt@...nel.org>,
	Pawel Moll <pawel.moll@....com>,
	Will Deacon <will.deacon@....com>,
	Catalin Marinas <catalin.marinas@....com>,
	linux-arm-kernel <linux-arm-kernel@...ts.infradead.org>
Subject: Re: [PATCH 2/2] arm64: dts: uniphier: change release address of spin-table

On Friday 15 April 2016 22:13:55 Masahiro Yamada wrote:
> 2016-04-15 22:05 GMT+09:00 Mark Rutland <mark.rutland@....com>:
> > On Fri, Apr 15, 2016 at 07:30:47PM +0900, Masahiro Yamada wrote:
> >> The 8-byte register located at 0x59801200 on this SoC is dedicated
> >> for waking up secondary CPUs.  We can use it and save normal memory.
> >
> > Generally, it is not safe to use MMIO registers to back spin-table. The
> > kernel maps the spin table location with cacheable attributes, so there
> > may be speculative accesses to any registes in the same (64K) page, and
> > a writeback may be larger than the 8-byte register width (which the
> > device might not accept, triggering an SError).
> >
> > Given that, I do not think this is a good idea.
> 
> I did not know this.  Thanks for your advice!
> 
> 
> Arnd, Olof
> 
> Please drop this patch.
> (I think 1/2 is still OK.)
> 

Should patch 1 be applied as a bugfix for 4.6 instead?

	Arnd

Powered by blists - more mailing lists