linux-kernel - Re: [PATCH 15/19] mfd: Don't convert just one IRQ using irqdomain if a range is provided

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, 7 Sep 2012 13:46:12 +0100
From:	Lee Jones <lee.jones@...aro.org>
To:	Arnd Bergmann <arnd@...db.de>
Cc:	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
	STEricsson_nomadik_linux@...t.st.com, linus.walleij@...ricsson.com,
	Samuel Ortiz <sameo@...ux.intel.com>
Subject: Re: [PATCH 15/19] mfd: Don't convert just one IRQ using irqdomain if
 a range is provided

On Fri, Sep 07, 2012 at 12:35:41PM +0000, Arnd Bergmann wrote:
> On Friday 07 September 2012, Lee Jones wrote:
> > MFD core code attempts to convert specified hardware (local) IRQ
> > numbers to virtual-IRQs, which something Linux can understand. This
> > works great when only one IRQ is specified. However, converting
> > entire ranges is currently unsupported. If this occurs we issue a
> > kernel warning to inform the user of this, but we continue to
> > convert the first specified IRQ anyway and replace the range. This
> > is not the correct behaviour. This patch ensures that if a range
> > is specified, it is left untouched.
> > 
> > CC: Samuel Ortiz <sameo@...ux.intel.com>
> > Signed-off-by: Lee Jones <lee.jones@...aro.org>
> 
> I don't see the advantage of the change. The warning already tells
> us that the input to mfd_add_device was incorrect, so nothing the
> function does can reliably fix it. Leaving the resource empty
> is just as wrong as listing only the first interrupt.

My thinking was to leave them in a range, then have the target driver
convert each entry in the range manually. But what you're saying is
that no registration should be attempted using ranges at all? What if
the range was vast? Surely a resource array a few hundred lines long
isn't correct either? My immediate example would be "GPIO_INT6", which
has 31 lines. Do you want them all splitting out individually?

-- 
Lee Jones
Linaro ST-Ericsson Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
--
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/