From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-lf1-x144.google.com ([2a00:1450:4864:20::144]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gKO9X-0002up-CF for barebox@lists.infradead.org; Wed, 07 Nov 2018 13:45:53 +0000 Received: by mail-lf1-x144.google.com with SMTP id d7-v6so11523361lfi.2 for ; Wed, 07 Nov 2018 05:45:38 -0800 (PST) Date: Wed, 7 Nov 2018 16:45:23 +0300 From: Peter Mamonov Message-ID: <20181107134522.y7awdhz2uowjnqh7@localhost.localdomain> References: <20181106161407.20974-1-l.stach@pengutronix.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20181106161407.20974-1-l.stach@pengutronix.de> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH] commands: mem: truncate mem device size to fit the loff_t file size To: Lucas Stach Cc: barebox@lists.infradead.org Hi, Lucas, On Tue, Nov 06, 2018 at 05:14:07PM +0100, Lucas Stach wrote: > On 64bit arches the file covering the whole address space is larger than > what can be represented in the loff_t type (s64) used for the file size. > Thus the size of this device is interpreted as negative in a lot of > places. Fix this by truncating the size to fit the file size type. While this is probably an appropriate solution for some architectures, it will cause problems on MIPS64. The root of evil is MIPS64 address space segmentation: https://docplayer.net/docs-images/25/4553906/images/21-0.png). Most notably your patch prevents access to the xkphys segment, where most peripheral devices of a SoC are accessible. Regards, Peter > > Signed-off-by: Lucas Stach > --- > commands/mem.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/commands/mem.c b/commands/mem.c > index eb91ade05a88..cdd7a492d0d5 100644 > --- a/commands/mem.c > +++ b/commands/mem.c > @@ -96,7 +96,8 @@ static int mem_probe(struct device_d *dev) > dev->priv = cdev; > > cdev->name = (char*)dev->resource[0].name; > - cdev->size = (unsigned long)resource_size(&dev->resource[0]); > + cdev->size = min(resource_size(&dev->resource[0]), > + (unsigned long long)S64_MAX); > cdev->ops = &memops; > cdev->dev = dev; > > -- > 2.19.1 > > > _______________________________________________ > barebox mailing list > barebox@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/barebox _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox