linux-kernel - Re: [PATCH 1/3] of: Add prefix parameter to of_modalias

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: <20120520060802.03CE73E03B8@localhost>
Date:	Sun, 20 May 2012 00:08:01 -0600
From:	Grant Likely <grant.likely@...retlab.ca>
To:	David Daney <ddaney.cavm@...il.com>,
	devicetree-discuss@...ts.ozlabs.org,
	Rob Herring <rob.herring@...xeda.com>,
	spi-devel-general@...ts.sourceforge.net
Cc:	linux-kernel@...r.kernel.org, linux-mips@...ux-mips.org,
	linux-doc@...r.kernel.org, David Daney <david.daney@...ium.com>,
	Liam Girdwood <lrg@...com>, Timur Tabi <timur@...escale.com>,
	Mark Brown <broonie@...nsource.wolfsonmicro.com>,
	Jaroslav Kysela <perex@...ex.cz>, Takashi Iwai <tiwai@...e.de>,
	alsa-devel@...a-project.org, linuxppc-dev@...ts.ozlabs.org
Subject: Re: [PATCH 1/3] of: Add prefix parameter to of_modalias_node().

On Sat, 19 May 2012 23:54:36 -0600, Grant Likely <grant.likely@...retlab.ca> wrote:
> On Fri, 11 May 2012 15:05:21 -0700, David Daney <ddaney.cavm@...il.com> wrote:
> > From: David Daney <david.daney@...ium.com>
> > 
> > When generating MODALIASes, it is convenient to add things like "spi:"
> > or "i2c:" to the front of the strings.  This allows the standard
> > modprobe to find the right driver when automatically populating bus
> > children from the device tree structure.
> > 
> > Add a prefix parameter, and adjust callers.  For
> > of_register_spi_devices() use the "spi:" prefix.
> > 
> > Signed-off-by: David Daney <david.daney@...ium.com>
> 
> Applied, thanks.  Some notes below...

Wait... why is this necessary?  The module type prefix isn't stored in
the modalias value for any other bus type as far as I can see, and
with this series it appears that the "spi:" prefix may or may not be
present in the modalias.  That doesn't look right.

Why isn't prefixing spi: at uevent time sufficient?  IIUC, modprobe
depends on either UEVENT or the modalias attribute to know which
driver to probe.  It does look like the attribute is missing the spi:
prefix though.  Does the following change work instead of these two
patches?

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 3d8f662..da8aac7 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -51,7 +51,7 @@ modalias_show(struct device *dev, struct device_attribute *a, char *buf)
 {
        const struct spi_device *spi = to_spi_device(dev);
 
-       return sprintf(buf, "%s\n", spi->modalias);
+       return sprintf(buf, "%s%s\n", SPI_MODULE_PREFIX, spi->modalias);
 }

So, I've dropped this patch from my tree.  If the change above works
for you then I'll push it out.

g.
--
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/