linux-kernel - Re: [PATCH 01/10] of: Keep track of populated platform devices

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: <CAL_JsqJxWoxNL=P0SJm+Q1rTRGTpMkzmzTJDbFq2P1vPH4XxZQ@mail.gmail.com>
Date:	Mon, 28 Apr 2014 13:02:28 -0500
From:	Rob Herring <robherring2@...il.com>
To:	Pawel Moll <pawel.moll@....com>
Cc:	Grant Likely <grant.likely@...aro.org>,
	Rob Herring <robh+dt@...nel.org>,
	Samuel Ortiz <sameo@...ux.intel.com>,
	Lee Jones <lee.jones@...aro.org>,
	Arnd Bergmann <arnd@...db.de>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Russell King <linux@....linux.org.uk>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>,
	"arm@...nel.org" <arm@...nel.org>,
	"devicetree@...r.kernel.org" <devicetree@...r.kernel.org>
Subject: Re: [PATCH 01/10] of: Keep track of populated platform devices

On Mon, Apr 28, 2014 at 12:57 PM, Pawel Moll <pawel.moll@....com> wrote:
> In "Device Tree powered" systems, platform devices are usually
> massively populated with of_platform_populate() call, executed
> at some level of initcalls, either by generic architecture
> or by platform-specific code.
>
> There are situations though where certain devices must be
> created (and bound with drivers) before all the others.
> This presents a challenge, as devices created explicitly
> would be created again by of_platform_populate().
>
> This patch tries to solve that issue in a generic way,
> adding a "populated" flag for a DT node description.
> Once set, this device will never be created again via
> of_* API, so of_platform_populate() will skip such nodes
> (and its children) in a similar way to the non-available
> ones.
>
> Cc: devicetree@...r.kernel.org
> Signed-off-by: Pawel Moll <pawel.moll@....com>
> ---
>  drivers/of/platform.c | 10 ++++++++--
>  include/linux/of.h    |  1 +
>  2 files changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> index 404d1da..0ae757a 100644
> --- a/drivers/of/platform.c
> +++ b/drivers/of/platform.c
> @@ -204,7 +204,8 @@ static struct platform_device *of_platform_device_create_pdata(
>  {
>         struct platform_device *dev;
>
> -       if (!of_device_is_available(np))
> +       if (!of_device_is_available(np) ||
> +                       of_node_check_flag(np, OF_POPULATED))

This and the amba case should be a test_and_set operation to avoid a
race condition.

Rob
--
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/