From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexandre Belloni Subject: Re: [PATCH] serial: atmel: fix compiler warning on address cast Date: Thu, 8 Oct 2015 12:38:35 +0200 Message-ID: <20151008103835.GF3485@piout.net> References: <1444064452-12285-1-git-send-email-andre.przywara@arm.com> <20151008090148.GE3485@piout.net> <20151008093749.GB32532@n2100.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20151008093749.GB32532@n2100.arm.linux.org.uk> Sender: linux-kernel-owner@vger.kernel.org To: Russell King - ARM Linux Cc: Greg Kroah-Hartman , Andre Przywara , Jiri Slaby , Nicolas Ferre , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= , linux-arm-kernel@lists.infradead.org List-Id: linux-serial@vger.kernel.org On 08/10/2015 at 10:37:49 +0100, Russell King - ARM Linux wrote : > On Thu, Oct 08, 2015 at 11:01:48AM +0200, Alexandre Belloni wrote: > > On 05/10/2015 at 18:00:52 +0100, Andre Przywara wrote : > > > Turning on KVM and LPAE support on top of a multi_v7_defconfig will > > > produce a compiler warning in the Atmel serial driver: > > > drivers/tty/serial/atmel_serial.c: In function 'atmel_verify_port': > > > drivers/tty/serial/atmel_serial.c:2299:6: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] > > > if ((void *)port->mapbase != ser->iomem_base) > > > ^ > > > > > > Fix that by using the cast on the right hand side instead, as similar > > > code already does in other drivers. > > > > > > Signed-off-by: Andre Przywara > > Acked-by: Alexandre Belloni > > Hmm, this actually points at a problem, and the cast screems out about it. > Think about it, can you guess what it is? > My understanding of the issue is that port->mapbase is a 64bit resource_size_t, and is larger than void * hence the warning. Casting iomem_base to unsigned long seems safe to me, am I wrong? -- Alexandre Belloni, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com