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: <54B502B9.9030609@ti.com>
Date:	Tue, 13 Jan 2015 13:34:17 +0200
From:	Tomi Valkeinen <tomi.valkeinen@...com>
To:	Sudip Mukherjee <sudipm.mukherjee@...il.com>
CC:	Antonino Daplas <adaplas@...il.com>,
	Jean-Christophe Plagniol-Villard <plagnioj@...osoft.com>,
	<linux-fbdev@...r.kernel.org>, <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] fbdev: savage: remove unused variable

On 06/01/15 15:12, Sudip Mukherjee wrote:
> vga_in8() was storing the return value in tmp, but that return value
> was never used again. so it should be safe to remove those variables.
> 
> Signed-off-by: Sudip Mukherjee <sudip@...torindia.org>
> ---
> 
> just one doubt:
> vga_in8() is calling savage_in8() which is a readb().
> so in effect we are reading one byte from
> (par->mmio.vbase + 0x8000 + 0x3da) and then discarding that value.
> so if we are discarding that value then why we are reading it?

Sometimes reading a HW register without actually using the returned
value has some effect. I don't know if there's a reason for that in this
case, though, as I'm not familiar with the HW.

In any case, it's safer to keep the read there as you did.

Queued for 3.20.

 Tomi



Download attachment "signature.asc" of type "application/pgp-signature" (820 bytes)

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ