Commit a3f916f2 authored by Dominik Brodowski's avatar Dominik Brodowski

pcmcia: disable pcmcia ioctl for !ARM, prepare for removal

The PCMCIA ioctl -- deprecated for years -- suffers from insufficient
locking. As it already has been deprecated for years, with its removal
long overdue, limit it to !SMP and !PREEMPT.

Furthermore, the last legitimate use of the ioctl to be reported
relates to the ARM architecture in 2008.[1] Attempts to resolve
this issue turned out unsuccessful so far.[2] Other usages have only
been reported as hear-say. If there are any legitiate and necessary
use-cases remaining, please speak out before the end of the grace
period until 2.6.3{5,6}(-rc1).

[1] http://lists.infradead.org/pipermail/linux-pcmcia/2008-April/005440.html
    see also: http://lkml.org/lkml/2008/2/27/291
[2] http://lists.infradead.org/pipermail/linux-pcmcia/2008-April/005450.html
    http://lists.infradead.org/pipermail/linux-pcmcia/2010-January/006740.html
    see also: http://lists.infradead.org/pipermail/linux-pcmcia/2008-April/005453.html

CC: Russell King <rmk+kernel@arm.linux.org.uk>
CC: Alan Cox <alan@lxorguk.ukuu.org.uk>
CC: Robert P. J. Day <rpjday@crashcourse.ca>
CC: Jaswinder Singh Rajput <jaswinder@kernel.org>
CC: linux-kernel@vger.kernel.org
Signed-off-by: default avatarDominik Brodowski <linux@dominikbrodowski.net>
parent 6e83ee07
...@@ -138,19 +138,25 @@ Who: Mauro Carvalho Chehab <mchehab@infradead.org> ...@@ -138,19 +138,25 @@ Who: Mauro Carvalho Chehab <mchehab@infradead.org>
--------------------------- ---------------------------
What: PCMCIA control ioctl (needed for pcmcia-cs [cardmgr, cardctl]) What: PCMCIA control ioctl (needed for pcmcia-cs [cardmgr, cardctl])
When: November 2005 When: 2.6.35/2.6.36
Files: drivers/pcmcia/: pcmcia_ioctl.c Files: drivers/pcmcia/: pcmcia_ioctl.c
Why: With the 16-bit PCMCIA subsystem now behaving (almost) like a Why: With the 16-bit PCMCIA subsystem now behaving (almost) like a
normal hotpluggable bus, and with it using the default kernel normal hotpluggable bus, and with it using the default kernel
infrastructure (hotplug, driver core, sysfs) keeping the PCMCIA infrastructure (hotplug, driver core, sysfs) keeping the PCMCIA
control ioctl needed by cardmgr and cardctl from pcmcia-cs is control ioctl needed by cardmgr and cardctl from pcmcia-cs is
unnecessary, and makes further cleanups and integration of the unnecessary and potentially harmful (it does not provide for
proper locking), and makes further cleanups and integration of the
PCMCIA subsystem into the Linux kernel device driver model more PCMCIA subsystem into the Linux kernel device driver model more
difficult. The features provided by cardmgr and cardctl are either difficult. The features provided by cardmgr and cardctl are either
handled by the kernel itself now or are available in the new handled by the kernel itself now or are available in the new
pcmciautils package available at pcmciautils package available at
http://kernel.org/pub/linux/utils/kernel/pcmcia/ http://kernel.org/pub/linux/utils/kernel/pcmcia/
Who: Dominik Brodowski <linux@brodo.de>
For all architectures except ARM, the associated config symbol
has been removed from kernel 2.6.34; for ARM, it will be likely
be removed from kernel 2.6.35. The actual code will then likely
be removed from kernel 2.6.36.
Who: Dominik Brodowski <linux@dominikbrodowski.net>
--------------------------- ---------------------------
......
...@@ -51,17 +51,23 @@ config PCMCIA_LOAD_CIS ...@@ -51,17 +51,23 @@ config PCMCIA_LOAD_CIS
config PCMCIA_IOCTL config PCMCIA_IOCTL
bool "PCMCIA control ioctl (obsolete)" bool "PCMCIA control ioctl (obsolete)"
depends on PCMCIA depends on PCMCIA && ARM && !SMP && !PREEMPT
default y default y
help help
If you say Y here, the deprecated ioctl interface to the PCMCIA If you say Y here, the deprecated ioctl interface to the PCMCIA
subsystem will be built. It is needed by cardmgr and cardctl subsystem will be built. It is needed by the deprecated pcmcia-cs
(pcmcia-cs) to function properly. tools (cardmgr, cardctl) to function properly.
You should use the new pcmciautils package instead (see You should use the new pcmciautils package instead (see
<file:Documentation/Changes> for location and details). <file:Documentation/Changes> for location and details).
If unsure, say Y. This config option will most likely be removed from kernel 2.6.35,
the associated code from kernel 2.6.36.
As the PCMCIA ioctl is not locking safe, it depends on !SMP and
!PREEMPT.
If unsure, say N.
config CARDBUS config CARDBUS
bool "32-bit CardBus support" bool "32-bit CardBus support"
......
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