Commit Graph

78 Commits

Author SHA1 Message Date
Al Viro dd0fc66fb3 [PATCH] gfp flags annotations - part 1
- added typedef unsigned int __nocast gfp_t;

 - replaced __nocast uses for gfp flags with gfp_t - it gives exactly
   the same warnings as far as sparse is concerned, doesn't change
   generated code (from gcc point of view we replaced unsigned int with
   typedef) and documents what's going on far better.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-08 15:00:57 -07:00
Bill Nottingham 3e51377dc4 [PATCH] fix class symlinks in sysfs
The class symlinks in sysfs don't properly handle changing device names.

To demonstrate, rename your network device from eth0 to eth1. Your
pci (or usb, or whatever) device will still have a 'net:eth0' link,
except now it points to /sys/class/net/eth1.

The attached patch makes sure the class symlink name changes when
the class device name changes. It isn't 100% correct, it should be
using sysfs_rename_link. Unfortunately, sysfs_rename_link doesn't exist.

Signed-off-by: Bill Nottingham <notting@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-22 07:58:24 -07:00
Daniel Ritz 4c898c7f2f [PATCH] Driver Core: fis bus rescan devices race
bus_rescan_devices_helper() does not hold the dev->sem when it checks for
!dev->driver().  device_attach() holds the sem, but calls again
device_bind_driver() even when dev->driver is set.

What happens is that a first device_attach() call (module insertion time)
is on the way binding the device to a driver.  Another thread calls
bus_rescan_devices().  Now when bus_rescan_devices_helper() checks for
dev->driver it is still NULL 'cos the the prior device_attach() is not yet
finished.  But as soon as the first one releases the dev->sem the second
device_attach() tries to rebind the already bound device again.
device_bind_driver() does this blindly which leads to a corrupt
driver->klist_devices list (the device links itself, the head points to the
device).  Later a call to device_release_driver() sets dev->driver to NULL
and breaks the link it has to itself on knode_driver.  Rmmoding the driver
later calls driver_detach() which leads to an endless loop 'cos the list
head in klist_devices still points to the device.  And since dev->driver is
NULL it's stuck with the same device forever.  Boom.  And rmmod hangs.

Very easy to reproduce with new-style pcmcia and a 16bit card.  Just loop
modprobe <pcmcia-modules> ;cardctl eject; rmmod <card driver, pcmcia
modules>.

Easiest fix is to check if the device is already bound to a driver in
device_bind_driver().  This avoids the double binding.

Signed-off-by: Daniel Ritz <daniel.ritz@gmx.ch>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-22 07:58:24 -07:00
Jiri Slaby 4aed0644d6 [PATCH] drivers/base/*: use kzalloc instead of kmalloc+memset
Fixes a bunch of memset bugs too.

Signed-off-by: Lion Vollnhals <webmaster@schiggl.de>
Signed-off-by: Jiri Slaby <xslaby@fi.muni.cz>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-13 08:22:27 -07:00
Victor Fusco 3a11ec5e50 [PATCH] dmapool: Fix "nocast type" warnings
Fix the sparse warning "implicit cast to nocast type"

Signed-off-by: Victor Fusco <victor@cetuc.puc-rio.br>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 10:06:29 -07:00
Linus Torvalds caf39e87cc [SCSI] Re-do "final klist fixes"
With the previous commit that introduces the klist enhancements, we can
now re-do 2b7d6a8cb9 again.
2005-09-07 18:44:33 -07:00
James Bottomley 34bb61f9dd [PATCH] fix klist semantics for lists which have elements removed on traversal
The problem is that klists claim to provide semantics for safe traversal of
lists which are being modified.  The failure case is when traversal of a
list causes element removal (a fairly common case).  The issue is that
although the list node is refcounted, if it is embedded in an object (which
is universally the case), then the object will be freed regardless of the
klist refcount leading to slab corruption because the klist iterator refers
to the prior element to get the next.

The solution is to make the klist take and release references to the
embedding object meaning that the embedding object won't be released until
the list relinquishes the reference to it.

(akpm: fast-track this because it's needed for the 2.6.13 scsi merge)

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 18:26:54 -07:00
Linus Torvalds df4edad178 [SCSI] Revert "final klist fixes"
Revert commit 2b7d6a8cb9.

The "fix" was known to not even compile.  Duh.  That's not a fix.
That's just stupid.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 17:50:58 -07:00
Linus Torvalds 0481990b75 Merge master.kernel.org:/pub/scm/linux/kernel/git/jejb/scsi-for-linus-2.6 2005-09-07 17:31:27 -07:00
Abhay Salunke 6e3eaab020 [PATCH] modified firmware_class.c to support no hotplug
Upgrade the request_firmware_nowait function to not start the hotplug
action on a firmware update.

This patch is tested along with dell_rbu driver on i386 and x86-64 systems.

Signed-off-by: Abhay Salunke <Abhay_Salunke@dell.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:26 -07:00
James Bottomley 17fa53da12 Merge by hand (conflicts in sd.c) 2005-09-06 17:52:54 -05:00
James Bottomley d856f1e337 [PATCH] klist: fix klist to have the same klist_add semantics as list_head
at the moment, the list_head semantics are

list_add(node, head)

whereas current klist semantics are

klist_add(head, node)

This is bound to cause confusion, and since klist is the newcomer, it
should follow the list_head semantics.

I also added missing include guards to klist.h

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-05 16:03:13 -07:00
Jesper Juhl fef6ec8dd9 [PATCH] Driver core: small cleanup; remove check for NULL before kfree() in driver core
Remove needless checking of variable for NULL before calling kfree() on it.
Applies to 2.6.13-rc6-git9

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-05 16:03:13 -07:00
Shaohua Li ceaeade1f9 [PATCH] Driver core: hande sysdev suspend failure
This patch adds the return value check for sysdev suspend and does
restore in failure case. Send the patch to pm-list, but seems lost, so I
resend it.

Signed-off-by: Shaohua Li<shaohua.li@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-05 16:03:12 -07:00
Dmitry Torokhov 76d1ce00bd [PATCH] Driver core: link device and all class devices derived from it.
Driver core: link device and all class devices derived from it.

To ease the task of locating class devices derived from a certain
device create symlinks from parent device to its class devices.
Change USB host class device name from usbX to usb_hostX to avoid
conflict when creating aforementioned links.

Tweaked by Greg to have the symlink be "class_name:class_device_name" in
order to prevent duplicate links.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-05 16:03:10 -07:00
Greg Kroah-Hartman d65da6eae1 [PATCH] Fix manual binding infinite loop
Fix for manual binding of drivers to devices.  Problem is if you pass in
a valid device id, but the driver refuses to bind.  Infinite loop as
write() tries to resubmit the data it just sent.

Thanks to Michal Ostrowski <mostrows@watson.ibm.com> for pointing the
problem out.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-05 16:03:09 -07:00
Pavel Machek ca078bae81 [PATCH] swsusp: switch pm_message_t to struct
This adds type-checking to pm_message_t, so that people can't confuse it
with int or u32.  It also allows us to fix "disk yoyo" during suspend (disk
spinning down/up/down).

[We've tried that before; since that cpufreq problems were fixed and I've
tried make allyes config and fixed resulting damage.]

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Alexander Nyberg <alexn@telia.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:16 -07:00
Martin Hicks c07e02db76 [PATCH] VM: add page_state info to per-node meminfo
Add page_state info to the per-node meminfo file in sysfs.  This is mostly
just for informational purposes.

The lack of this information was brought up recently during a discussion
regarding pagecache clearing, and I put this patch together to test out one
of the suggestions.

It seems like interesting info to have, so I'm submitting the patch.

Signed-off-by: Martin Hicks <mort@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:05:49 -07:00
James Bottomley 2b7d6a8cb9 [SCSI] attribute container final klist fixes
Since the attribute container deletes from a klist while it's walking
it, it is vulnerable to the problem (and fix) here:

http://marc.theaimsgroup.com/?l=linux-scsi&m=112485448830217

The attached fixes this (but won't compile without the above).

It also fixes the logical reversal in the traversal loop which meant
that we were never actually traversing the loop to hit this bug in the
first place.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-08-30 22:44:32 -05:00
James Bottomley 53c165e0a6 [SCSI] correct attribute_container list usage
One of the changes in the attribute_container code in the scsi-misc tree
was to add a lock to protect the list of devices per container.  This,
unfortunately, leads to potential scheduling while atomic problems if
there's a sleep in the function called by a trigger.

The correct solution is to use the kernel klist infrastructure instead
which allows lockless traversal of a list.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-08-30 22:44:20 -05:00
James Bottomley 7a93aef7fb Merge HEAD from ../scsi-misc-2.6-tmp 2005-08-28 11:18:35 -05:00
James Bottomley ebd8bb7647 [SCSI] fix transport class corner case after rework
If your transport class sets the ATTRIBUTE_CONTAINER_NO_CLASSDEVS flag,
then its configure method never gets called.  This patch fixes that so
that the configure method is called with a NULL classdev.

Also remove a spurious inverted comma in the transport_class comments.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-08-28 11:14:06 -05:00
Greg KH 518e654083 [PATCH] Fix manual binding infinite loop
Fix for manual binding of drivers to devices.  Problem is if you pass in
a valid device id, but the driver refuses to bind.  Infinite loop as
write() tries to resubmit the data it just sent.

Thanks to Michal Ostrowski <mostrows@watson.ibm.com> for pointing the
problem out.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-17 22:02:25 -07:00
Maneesh Soni 208f3d6175 [PATCH] Driver core: potentially fix use after free in class_device_attr_show
This moves the code to free devt_attr from class_device_del() to
class_dev_release() which is called after the last reference to the
corresponding kobject() is gone.

This allows us to keep the devt_attr alive while the corresponding
sysfs file is open.

Signed-off-by: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-16 21:06:24 -07:00
James Bottomley d0a7e57400 [SCSI] correct transport class abstraction to work outside SCSI
I recently tried to construct a totally generic transport class and
found there were certain features missing from the current abstract
transport class.  Most notable is that you have to hang the data on the
class_device but most of the API is framed in terms of the generic
device, not the class_device.

These changes are two fold

- Provide the class_device to all of the setup and configure APIs
- Provide and extra API to take the device and the attribute class and
  return the corresponding class_device

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-08-14 17:21:27 -05:00
Len Brown 5028770a42 [ACPI] merge acpi-2.6.12 branch into latest Linux 2.6.13-rc...
Signed-off-by: Len Brown <len.brown@intel.com>
2005-07-12 17:21:56 -04:00
Alexey Starikovskiy e2a5b420f7 [ACPI] ACPI poweroff fix
Register an "acpi" system device to be notified of shutdown preparation.
This depends on CONFIG_PM

http://bugzilla.kernel.org/show_bug.cgi?id=4041

Signed-off-by: Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2005-07-11 23:20:49 -04:00
Patrick Mochel d62c0f9fd2 [PATCH] Driver core: Use klist_del() instead of klist_remove().
Use klist_del() instead of klist_remove() when unregistering devices.
This will prevent a deadlock when executing a recursive unregister using
device_for_each_child().

Signed-off-by Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-29 22:48:05 -07:00
Greg Kroah-Hartman 23d3d602cb [PATCH] driver core: change bus_rescan_devices to return void
No one was looking at the return value of bus_rescan_devices, and it
really wasn't anything that anyone in the kernel would ever care about.
So change it which enabled some counting code to be removed also.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-29 22:48:04 -07:00
Greg Kroah-Hartman afdce75f1e [PATCH] driver core: Add the ability to bind drivers to devices from userspace
This adds a single file, "bind", to the sysfs directory of every driver
registered with the driver core.  To bind a device to a driver, write
the bus id of the device you wish to bind to that specific driver to the
"bind" file (remember to not add a trailing \n).  If that bus id matches
a device on that bus, and it does not currently have a driver bound to
it, the probe sequence will be initiated with that driver and device.

Note, this requires that the driver itself be willing and able to accept
that device (usually through a device id type table).  This patch does
not make it possible to override the driver's id table.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-29 22:48:04 -07:00
Greg Kroah-Hartman 151ef38f7c [PATCH] driver core: Add the ability to unbind drivers to devices from userspace
This adds a single file, "unbind", to the sysfs directory of every
device that is currently bound to a driver.  To unbind the driver from
the device, write anything to this file and they will be disconnected
from each other.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-29 22:48:04 -07:00
Cornelia Huck 0edb586049 [PATCH] driver core: add bus_find_device & driver_find_device functions
Add bus_find_device() and driver_find_device() which allow searching for a
device in the bus's resp. the driver's klist and obtain a reference on it.

Signed-off-by: Cornelia Huck <cohuck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-29 22:48:03 -07:00
Stanislaw W. Gruszka b92eac01c3 [PATCH] request_firmware(): avoid race conditions
Avoid race occurs when some process have open file descriptor for class
device attributes and already firmware allocated memory are freed.  Don't
allow negative loading timeout.

Signed-off-by: Stanislaw W. Gruszka <stf_xl@wp.pl>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 21:20:30 -07:00
Nathan Lynch fb69c3907e [PATCH] generate hotplug events for cpu online
We already do kobject_hotplug for cpu offline; this adds a kobject_hotplug
call for the online case.  This is being requested by developers of an
application which wants to be notified about both kinds of events.

Signed-off-by: Nathan Lynch <ntl@pobox.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:24:31 -07:00
Ashok Raj 52a119feaa [PATCH] make smp_prepare_cpu to a weak function
I really wish smp_prepare_cpu() would disappear eventually.  In the interim
this is ideally a weak function, so we dont end up changing several places
to define this dummy in headers.

Today since the dummy declaration is done only in drivers/base/cpu.c but
the function is called in kernel/power/smp.c i get undefined reference in
my cpu hotplug code for x86_64 under development.

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:24:30 -07:00
Li Shaohua e1367daf3e [PATCH] cpu state clean after hot remove
Clean CPU states in order to reuse smp boot code for CPU hotplug.

Signed-off-by: Li Shaohua<shaohua.li@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:24:30 -07:00
Greg Kroah-Hartman d377e85b53 [PATCH] driver core: Fix up the device_attach() error handling in bus_add_device()
Don't error out if something "bad" happens when trying to bind a driver to a
device.  We want the sysfs attributes to be present for later when we try to
tear down the device.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-22 23:01:10 -07:00
Christoph Lameter e7c8d5c995 [PATCH] node local per-cpu-pages
This patch modifies the way pagesets in struct zone are managed.

Each zone has a per-cpu array of pagesets.  So any particular CPU has some
memory in each zone structure which belongs to itself.  Even if that CPU is
not local to that zone.

So the patch relocates the pagesets for each cpu to the node that is nearest
to the cpu instead of allocating the pagesets in the (possibly remote) target
zone.  This means that the operations to manage pages on remote zone can be
done with information available locally.

We play a macro trick so that non-NUMA pmachines avoid the additional
pointer chase on the page allocator fastpath.

AIM7 benchmark on a 32 CPU SGI Altix

w/o patches:
Tasks    jobs/min  jti  jobs/min/task      real       cpu
    1      484.68  100       484.6769     12.01      1.97   Fri Mar 25 11:01:42 2005
  100    27140.46   89       271.4046     21.44    148.71   Fri Mar 25 11:02:04 2005
  200    30792.02   82       153.9601     37.80    296.72   Fri Mar 25 11:02:42 2005
  300    32209.27   81       107.3642     54.21    451.34   Fri Mar 25 11:03:37 2005
  400    34962.83   78        87.4071     66.59    588.97   Fri Mar 25 11:04:44 2005
  500    31676.92   75        63.3538     91.87    742.71   Fri Mar 25 11:06:16 2005
  600    36032.69   73        60.0545     96.91    885.44   Fri Mar 25 11:07:54 2005
  700    35540.43   77        50.7720    114.63   1024.28   Fri Mar 25 11:09:49 2005
  800    33906.70   74        42.3834    137.32   1181.65   Fri Mar 25 11:12:06 2005
  900    34120.67   73        37.9119    153.51   1325.26   Fri Mar 25 11:14:41 2005
 1000    34802.37   74        34.8024    167.23   1465.26   Fri Mar 25 11:17:28 2005

with slab API changes and pageset patch:

Tasks    jobs/min  jti  jobs/min/task      real       cpu
    1      485.00  100       485.0000     12.00      1.96   Fri Mar 25 11:46:18 2005
  100    28000.96   89       280.0096     20.79    150.45   Fri Mar 25 11:46:39 2005
  200    32285.80   79       161.4290     36.05    293.37   Fri Mar 25 11:47:16 2005
  300    40424.15   84       134.7472     43.19    438.42   Fri Mar 25 11:47:59 2005
  400    39155.01   79        97.8875     59.46    590.05   Fri Mar 25 11:48:59 2005
  500    37881.25   82        75.7625     76.82    730.19   Fri Mar 25 11:50:16 2005
  600    39083.14   78        65.1386     89.35    872.79   Fri Mar 25 11:51:46 2005
  700    38627.83   77        55.1826    105.47   1022.46   Fri Mar 25 11:53:32 2005
  800    39631.94   78        49.5399    117.48   1169.94   Fri Mar 25 11:55:30 2005
  900    36903.70   79        41.0041    141.94   1310.78   Fri Mar 25 11:57:53 2005
 1000    36201.23   77        36.2012    160.77   1458.31   Fri Mar 25 12:00:34 2005

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Shobhit Dayal <shobhit@calsoftinc.com>
Signed-off-by: Shai Fultheim <Shai@Scalex86.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:16 -07:00
Benjamin Herrenschmidt 42b16c051c [PATCH] Driver core: Don't "lose" devices on suspend on failure
I think we need this patch or we might "lose" devices to the dpm_irq_off
list if a failure occurs during the suspend process.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-20 15:15:37 -07:00
Yani Ioannou 74880c063b [PATCH] Driver Core: drivers/base - drivers/i2c/chips/adm1026.c: update device attribute callbacks
Signed-off-by: Yani Ioannou <yani.ioannou@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-20 15:15:32 -07:00
Yani Ioannou 54b6f35c99 [PATCH] Driver core: change device_attribute callbacks
This patch adds the device_attribute paramerter to the
device_attribute store and show sysfs callback functions, and passes a
reference to the attribute when the callbacks are called.

Signed-off-by: Yani Ioannou <yani.ioannou@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-20 15:15:31 -07:00
Hannes Reinecke ca2b94ba12 [PATCH] driver core: fix error handling in bus_add_device
The error handling in bus_add_device() and device_attach() is simply
non-existing. This patch propagates any error from device_attach to
the upper layers to allow for a proper recovery.

From: Hannes Reinecke <hare@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-20 15:15:31 -07:00
Keiichiro Tokunaga 4b45099b75 [PATCH] Driver core: unregister_node() for hotplug use
This adds a generic function 'unregister_node()'.
It is used to remove objects of a node going away
for hotplug.  All the devices on the node must be
unregistered before calling this function.

Signed-off-by: Keiichiro Tokunaga <tokunaga.keiich@jp.fujitsu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff -puN drivers/base/node.c~numa_hp_base drivers/base/node.c
2005-06-20 15:15:29 -07:00
Alan Stern c95a6b057b [PATCH] driver core: Fix races in driver_detach()
This patch is intended for your "driver" tree.  It fixes several subtle
races in driver_detach() and device_release_driver() in the driver-model
core.

The major change is to use klist_remove() rather than klist_del() when
taking a device off its driver's list.  There's no other way to guarantee
that the list pointers will be updated before some other driver binds to
the device.  For this to work driver_detach() can't use a klist iterator,
so the loop over the devices must be written out in full.  In addition the
patch protects against the possibility that, when a driver and a device
are unregistered at the same time, one may be unloaded from memory before
the other is finished using it.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-20 15:15:28 -07:00
Patrick Mochel 0d3e5a2e39 [PATCH] Driver Core: fix bk-driver-core kills ppc64
There's no check to see if the device is already bound to a driver, which
could do bad things.  The first thing to go wrong is that it will try to match
a driver with a device already bound to one.  In some cases (it appears with
USB with drivers/usb/core/usb.c::usb_match_id()), some drivers will match a
device based on the class type, so it would be common (especially for HID
devices) to match a device that is already bound.

The fun comes when ->probe() is called, it fails, then
driver_probe_device() does this:

	dev->driver = NULL;

Later on, that pointer could be be dereferenced without checking and cause
hell to break loose.

This problem could be nasty. It's very hardware dependent, since some
devices could have a different set of matching qualifiers than others.

Now, I don't quite see exactly where/how you were getting that crash.
You're dereferencing bad memory, but I'm not sure which pointer was bad
and where it came from, but it could have come from a couple of different
places.

The patch below will hopefully fix it all up for you. It's against
2.6.12-rc2-mm1, and does the following:

- Move logic to driver_probe_device() and comments uncommon returns:
  1 - If device is bound
  0 - If device not bound, and no error
  error - If there was an error.

- Move locking to caller of that function, since we want to lock a
  device for the entire time we're trying to bind it to a driver (to
  prevent against a driver being loaded at the same time).

- Update __device_attach() and __driver_attach() to do that locking.

- Check if device is already bound in __driver_attach()

- Update the converse device_release_driver() so it locks the device
  around all of the operations.

- Mark driver_probe_device() as static and remove export. It's an
  internal function, it should stay that way, and there are no other
  callers. If there is ever a need to export it, we can audit it as
  necessary.

Signed-off-by: Andrew Morton <akpm@osdl.org>
2005-06-20 15:15:27 -07:00
gregkh@suse.de b86c1df1f9 [PATCH] Driver core: Fix up the driver and device iterators to be quieter
Also stops looping over the lists when a match is found.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de
2005-06-20 15:15:27 -07:00
gregkh@suse.de 126eddfbf8 [PATCH] driver core: change export symbol for driver_for_each_device()
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Index: linux-2.6.12-rc2/drivers/base/driver.c
===================================================================
2005-06-20 15:15:24 -07:00
mochel@digitalimplant.org 4d12d2d953 [PATCH] Fix up bogus comment.
Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff -Nru a/drivers/base/driver.c b/drivers/base/driver.c
2005-06-20 15:15:23 -07:00
mochel@digitalimplant.org 36239577cf [PATCH] Use a klist for device child lists.
- Use klist iterator in device_for_each_child(), making it safe to use for
  removing devices.
- Remove unused list_to_dev() function.
- Kills all usage of devices_subsys.rwsem.

Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-20 15:15:23 -07:00
mochel@digitalimplant.org 0956af53af [PATCH] Call klist_del() instead of klist_remove().
- Can't wait on removing the current item in the list (the positive refcount *because*
  we are using it causes it to deadlock).

Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-20 15:15:19 -07:00