This fixes a memory-corrupting bug: not only does it cause the warning,
but as a result of dropping the refcount to zero, it causes the
pcmcia_socket0 device structure to be freed while it still has
references, causing slab caches corruption. A fatal oops quickly
follows this warning - often even just a 'dmesg' following the warning
causes the kernel to oops.
While testing suspend/resume on an ARM device with PCMCIA support, and a
CF card inserted, I found that after five suspend and resumes, the
kernel would complain, and shortly die after with slab corruption.
WARNING: at include/linux/kref.h:41 kobject_get+0x28/0x50()
As the message doesn't give a clue about which kobject, and the built-in
debugging in drivers/base/power/main.c happens too late, this was added
right before each get_device():
printk("%s: %p [%s] %u\n", __func__, dev, kobject_name(&dev->kobj), atomic_read(&dev->kobj.kref.refcount));
and on the 3rd s2ram cycle, the following behaviour observed:
On the 3rd suspend/resume cycle:
dpm_prepare: c1a0d998 [pcmcia_socket0] 3
dpm_suspend: c1a0d998 [pcmcia_socket0] 3
dpm_suspend_noirq: c1a0d998 [pcmcia_socket0] 3
dpm_resume_noirq: c1a0d998 [pcmcia_socket0] 3
dpm_resume: c1a0d998 [pcmcia_socket0] 3
dpm_complete: c1a0d998 [pcmcia_socket0] 2
4th:
dpm_prepare: c1a0d998 [pcmcia_socket0] 2
dpm_suspend: c1a0d998 [pcmcia_socket0] 2
dpm_suspend_noirq: c1a0d998 [pcmcia_socket0] 2
dpm_resume_noirq: c1a0d998 [pcmcia_socket0] 2
dpm_resume: c1a0d998 [pcmcia_socket0] 2
dpm_complete: c1a0d998 [pcmcia_socket0] 1
5th:
dpm_prepare: c1a0d998 [pcmcia_socket0] 1
dpm_suspend: c1a0d998 [pcmcia_socket0] 1
dpm_suspend_noirq: c1a0d998 [pcmcia_socket0] 1
dpm_resume_noirq: c1a0d998 [pcmcia_socket0] 1
dpm_resume: c1a0d998 [pcmcia_socket0] 1
dpm_complete: c1a0d998 [pcmcia_socket0] 0
------------[ cut here ]------------
WARNING: at include/linux/kref.h:41 kobject_get+0x28/0x50()
Modules linked in: ucb1x00_core
Backtrace:
[<c0212090>] (dump_backtrace+0x0/0x110) from [<c04799dc>] (dump_stack+0x18/0x1c)
[<c04799c4>] (dump_stack+0x0/0x1c) from [<c021cba0>] (warn_slowpath_common+0x50/0x68)
[<c021cb50>] (warn_slowpath_common+0x0/0x68) from [<c021cbdc>] (warn_slowpath_null+0x24/0x28)
[<c021cbb8>] (warn_slowpath_null+0x0/0x28) from [<c0335374>] (kobject_get+0x28/0x50)
[<c033534c>] (kobject_get+0x0/0x50) from [<c03804f4>] (get_device+0x1c/0x24)
[<c0388c90>] (dpm_complete+0x0/0x1a0) from [<c0389cc0>] (dpm_resume_end+0x1c/0x20)
...
Looking at commit 7b24e79882 ("pcmcia: split up central event handler"),
the following change was made to cs.c:
return 0;
}
#endif
-
- send_event(skt, CS_EVENT_PM_RESUME, CS_EVENT_PRI_LOW);
+ if (!(skt->state & SOCKET_CARDBUS) && (skt->callback))
+ skt->callback->early_resume(skt);
return 0;
}
And the corresponding change in ds.c is from:
-static int ds_event(struct pcmcia_socket *skt, event_t event, int priority)
-{
- struct pcmcia_socket *s = pcmcia_get_socket(skt);
...
- switch (event) {
...
- case CS_EVENT_PM_RESUME:
- if (verify_cis_cache(skt) != 0) {
- dev_dbg(&skt->dev, "cis mismatch - different card\n");
- /* first, remove the card */
- ds_event(skt, CS_EVENT_CARD_REMOVAL, CS_EVENT_PRI_HIGH);
- mutex_lock(&s->ops_mutex);
- destroy_cis_cache(skt);
- kfree(skt->fake_cis);
- skt->fake_cis = NULL;
- s->functions = 0;
- mutex_unlock(&s->ops_mutex);
- /* now, add the new card */
- ds_event(skt, CS_EVENT_CARD_INSERTION,
- CS_EVENT_PRI_LOW);
- }
- break;
...
- }
- pcmcia_put_socket(s);
- return 0;
-} /* ds_event */
to:
+static int pcmcia_bus_early_resume(struct pcmcia_socket *skt)
+{
+ if (!verify_cis_cache(skt)) {
+ pcmcia_put_socket(skt);
+ return 0;
+ }
+ dev_dbg(&skt->dev, "cis mismatch - different card\n");
+ /* first, remove the card */
+ pcmcia_bus_remove(skt);
+ mutex_lock(&skt->ops_mutex);
+ destroy_cis_cache(skt);
+ kfree(skt->fake_cis);
+ skt->fake_cis = NULL;
+ skt->functions = 0;
+ mutex_unlock(&skt->ops_mutex);
+ /* now, add the new card */
+ pcmcia_bus_add(skt);
+ return 0;
+}
As can be seen, the original function called pcmcia_get_socket() and
pcmcia_put_socket() around the guts, whereas the replacement code
calls pcmcia_put_socket() only in one path. This creates an imbalance
in the refcounting.
Testing with pcmcia_put_socket() put removed shows that the bug is gone:
dpm_suspend: c1a10998 [pcmcia_socket0] 5
dpm_suspend_noirq: c1a10998 [pcmcia_socket0] 5
dpm_resume_noirq: c1a10998 [pcmcia_socket0] 5
dpm_resume: c1a10998 [pcmcia_socket0] 5
dpm_complete: c1a10998 [pcmcia_socket0] 5
Tested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch (as1514) cleans up some places where new_id and remove_id
sysfs attributes are created and deleted. Handling both attributes in
a single routine rather than a pair of routines makes the code
smaller. It also prevents certain kinds of errors, like one we
currently have in the USB subsystem: The removeid attribute is often
created even when newid isn't (because the driver's no_dynamid_id flag
is set).
In the case of the PCMCIA subsystem, the newid attribute is created
but never explicitly deleted. The patch adds a deletion routine.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
As part of the removal of get_driver()/put_driver(), this patch
(as1511) changes all the places that add dynamic IDs for drivers.
Since these additions are done by writing to the drivers' sysfs
attribute files, and the attributes are removed when the drivers are
unregistered, there is no reason to take an extra reference to the
drivers.
The one exception is the pci-stub driver, which calls pci_add_dynid()
as part of its registration. But again, there's no reason to take an
extra reference here, because the driver can't be unloaded while it is
being registered.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Dmitry Torokhov <dmitry.torokhov@gmail.com>
CC: Jiri Kosina <jkosina@suse.cz>
CC: Jesse Barnes <jbarnes@virtuousgeek.org>
CC: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Const allows tables to be moved into text sections.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Insert PCMCIA device resources into the resource tree. However, this is
currently only implemented for sockets which do not statically map the
resources.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Introduce a new field into struct pcmcia_device named "resource" and of
type struct resource *, which contains the IO port ranges allocated for
this device. Memory window ranges and registration with the resource
trees will follow at a later date.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
As we only provide one way to set up resources now, we can remove
the resource-setup-related bitfield (except resource_setup_done).
In addition, pcmcia_state only consisted of one entry, so remove
this bitfield as well.
Suggested-by: Komuro <komurojun-mbn@nifty.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
The event callback for handling 16bit PCMCIA cards only needs to be
informed about a few events. Furthermore, send_event may already
only be called with skt->skt_mutex held, which also protects against
the module being removed behind the callback's back.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
The "present" flag was initialized too late -- possibly, a card
was already registered at this time, so re-setting the flag to 0
caused pcmcia_dev_present() to fail.
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Commit a8408c17 introduced a new check to pccard_validate_cis(),
which avoids any "late" calls to this function. This broke the
insertion of cards which require a CIS override which changes
the number of card functions. Fix this by asserting that this
is _not_ a late call, but a proper call early during the card
insertion process.
Fixes https://bugzilla.kernel.org/show_bug.cgi?id=16138
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
CC: <stable@kernel.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
As all cards to pcmcia_device_add() are already locked by skt_mutex, and
the critical sections inside this function are further protected by
ops_mutex, there's no need to keep a third lock around. Therfore, remove
pcmcia_add_device_lock.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Remove the dev_node declaration. We now only pass the device name
to the deprecated userspace tools.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Instead of the old pcmcia_request_irq() interface, drivers may now
choose between:
- calling request_irq/free_irq directly. Use the IRQ from *p_dev->irq.
- use pcmcia_request_irq(p_dev, handler_t); the PCMCIA core will
clean up automatically on calls to pcmcia_disable_device() or
device ejection.
- drivers still not capable of IRQF_SHARED (or not telling us so) may
use the deprecated pcmcia_request_exclusive_irq() for the time
being; they might receive a shared IRQ nonetheless.
CC: linux-bluetooth@vger.kernel.org
CC: netdev@vger.kernel.org
CC: linux-wireless@vger.kernel.org
CC: linux-serial@vger.kernel.org
CC: alsa-devel@alsa-project.org
CC: linux-usb@vger.kernel.org
CC: linux-ide@vger.kernel.org
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Setup the IRQ to be used by PCMCIA drivers already during the device
registration stage, making use of a new function pcmcia_setup_irq().
This will allow us to get rid of quite a lot of indirection in the
future.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
If the PCMCIA CIS changed before a resume event (e.g. due to
a card exchange while being suspended, possibly also during
a call to "pccardctl reset"), also set the function count to
zero so that the subsequent call to pccard_validate_cis() does
not fail.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Prevent PCMCIA_DEV_ID_MATCH_FUNC_ID from grabbing PFC-cards:
I changed the code, so that the first matching struct
pcmcia_device_id _PFC_ entry will mark the card has_pfc,
preventing PCMCIA_DEV_ID_MATCH_FUNC_ID to match.
[linux-pcmcia@lists.infradead.org: re-order commit message]
Signed-off-by: Alexander Kurz <linux@kbdbabel.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
pcmcia_dev_present is in and by itself buggy. Add a note specifying
why it is broken, and replace the broken locking -- taking a mutex
is a bad idea in IRQ context, from which this function is rarely
called -- by an atomic_t.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
If there are changes to the number of socket devices, we need to
start over in all cases: else pcmcia_request_configuration() might
get confused.
Reported-by: Alexander Kurz <linux@kbdbabel.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Commit aa584ca4 broke what 6cf5be51 had already fixed: there may
be four multifunction devices, but just two pseudo-multifunction
devices per PCMCIA card.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
In the future, we are going to be changing the lock type for struct
device (once we get the lockdep infrastructure properly worked out) To
make that changeover easier, and to possibly burry the lock in a
different part of struct device, let's create some functions to lock and
unlock a device so that no out-of-core code needs to be changed in the
future.
This patch creates the device_lock/unlock/trylock() functions, and
converts all in-tree users to them.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Dave Young <hidave.darkstar@gmail.com>
Cc: Ming Lei <tom.leiming@gmail.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Phil Carmody <ext-phil.2.carmody@nokia.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <len.brown@intel.com>
Cc: Magnus Damm <damm@igel.co.jp>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Alex Chiang <achiang@hp.com>
Cc: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrew Patterson <andrew.patterson@hp.com>
Cc: Yu Zhao <yu.zhao@intel.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: Wolfram Sang <w.sang@pengutronix.de>
Cc: CHENG Renquan <rqcheng@smu.edu.sg>
Cc: Oliver Neukum <oliver@neukum.org>
Cc: Frans Pop <elendil@planet.nl>
Cc: David Vrabel <david.vrabel@csr.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
As this is the socket thread (pccardd) starting up, we do not have
anything to wait for in ds.c. Instead, wait the same amount of time
in pccardd to allow userspace to catch up and - possibly - execute
pcmcia-socket-startup.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
The requery callback now also handles the addition of a second pseudo
multifunction device. Avoids messing with dev_{g,s}et_drvdata(), and
fixes any workqueue <-> skt_mutex deadlock.
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
After a CIS update -- or the finalization of the resource database --,
proceed with the re-scanning or re-querying of PCMCIA cards only in
a separate thread to avoid deadlocks.
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Even though we weren't calling a blocking function within the dynid
spinlock, we do not need a spinlock here but can and should be using
a mutex.
Reported-by: Jiri Slaby <jirislaby@gmail.com>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
replace pcmcia_socket->lock and pcmcia_dev_list_lock by using the
per-socket "ops_mutex", as we do neither need different locks
nor a spinlock here.
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
As PCMCIA is the only real user of CIS access functions, include
cistpl.c in the PCMCIA module, not in the PCMCIA & CardBus core
module.
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
As ds.c is the only real user of CIS access functions, call the
cleanup functions from ds.c, too.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
During a suspend/resume cycle, an user may change the card in the
PCMCIA/CardBus slot. The pcmcia_core can at least look at the
socket state to check whether it is the same.
For PCMCIA devices, move the detection and handling of such a
change to ds.c.
For CardBus devices, the PCI hotplug interface doesn't offer a "rescan"
facility which also _removes_ devices no longer to be found behind a
bridge. Therefore, remove and re-add all devices unconditionally.
CC: Jesse Barnes <jbarnes@virtuousgeek.org>
CC: Linus Torvalds <torvalds@linux-foundation.org>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
In runtime_resume(), do not throw away the return value of
pcmcia_dev_resume(), for we can use it (at least) in
pcmcia_store_pm_state(). This also fixes the pointless assignment
previosly seen there, as noted by Dan Carpenter.
CC: Dan Carpenter <error27@gmail.com>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Fix several CodingStyle issues in drivers/pcmcia/ . checkpatch.pl no longer
reports errors in the PCMCIA core. The remaining warnings mostly relate to
wrong indent -- PCMCIA historically used 4 spaces --, to lines over 80
characters and to hundreds of typedefs. The cleanup of those will follow
in the future.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
As all in-tree drivers have been converted to not use cs_error() any more,
drop these functions and definitions, and update the Documentation.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Use the generic "dynamic debug" infrastructure instead of
CONIG_PCMCIA_DEBUG in the PCMCIA core (pcmcia.ko and pcmcia_core.ko). To
enable debugging, enable CONFIG_DYNAMIC_DEBUG, mount debugfs and
$ echo -n 'module pcmcia_core +p' > /sys/kernel/debug/dynamic_debug/control
for the complete module "pcmcia_core", for example. For more detailled
instructions, please see Documentation/dynamic-debug-howto.txt
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
