[PATCH 5/5] pcmcia: disable pcmcia ioctl for !ARM, prepare for removal

From: Dominik Brodowski
Date: Wed Mar 03 2010 - 03:02:54 EST

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
see also: http://lists.infradead.org/pipermail/linux-pcmcia/2008-April/005453.html

CC: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>
CC: Alan Cox <alan@xxxxxxxxxxxxxxxxxxx>
CC: Robert P. J. Day <rpjday@xxxxxxxxxxxxxx>
CC: Jaswinder Singh Rajput <jaswinder@xxxxxxxxxx>
CC: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
Documentation/feature-removal-schedule.txt | 12 +++++++++---
drivers/pcmcia/Kconfig | 14 ++++++++++----
2 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index 732b1fa..3e57a75 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -138,19 +138,25 @@ Who: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxx>

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
Why: With the 16-bit PCMCIA subsystem now behaving (almost) like a
normal hotpluggable bus, and with it using the default kernel
infrastructure (hotplug, driver core, sysfs) keeping the PCMCIA
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
difficult. The features provided by cardmgr and cardctl are either
handled by the kernel itself now or are available in the new
pcmciautils package available at
-Who: Dominik Brodowski <linux@xxxxxxxx>
+ 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@xxxxxxxxxxxxxxxxxxxx>


diff --git a/drivers/pcmcia/Kconfig b/drivers/pcmcia/Kconfig
index 0a6601c..d189e47 100644
--- a/drivers/pcmcia/Kconfig
+++ b/drivers/pcmcia/Kconfig
@@ -51,17 +51,23 @@ config PCMCIA_LOAD_CIS

bool "PCMCIA control ioctl (obsolete)"
- depends on PCMCIA
+ depends on PCMCIA && ARM && !SMP && !PREEMPT
default y
If you say Y here, the deprecated ioctl interface to the PCMCIA
- subsystem will be built. It is needed by cardmgr and cardctl
- (pcmcia-cs) to function properly.
+ subsystem will be built. It is needed by the deprecated pcmcia-cs
+ tools (cardmgr, cardctl) to function properly.

You should use the new pcmciautils package instead (see
<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
+ If unsure, say N.

config CARDBUS
bool "32-bit CardBus support"

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