Got the following oops just before reboot:

Unable to handle kernel NULL pointer dereference at virtual address 00000000
[<8028d300>] (__list_del_entry+0x44/0xac)
[<802e3320>] (__fw_load_abort.part.13+0x1c/0x50)
[<802e337c>] (fw_shutdown_notify+0x28/0x50)
[<80034f80>] (notifier_call_chain.isra.1+0x5c/0x9c)
[<800350ec>] (__blocking_notifier_call_chain+0x44/0x58)
[<80035114>] (blocking_notifier_call_chain+0x14/0x18)
[<80035d64>] (kernel_restart_prepare+0x14/0x38)
[<80035d94>] (kernel_restart+0xc/0x50)

The following race condition triggers here:

  _request_firmware_load()
  device_create_file(...)
  kobject_uevent(...)
  (schedule)
                                       (resume)
                                       firmware_loading_store(1)
                                       firmware_loading_store(0)
                                       list_del_init(&buf->pending_list)
                                       (schedule)
  (resume)
  list_add(&buf->pending_list, &pending_fw_head);
  wait_for_completion(&buf->completion);

causing an oops later when walking pending_list after the firmware has
been released.

The proposed fix is to move the list_add() before sysfs attribute
creation.

Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Acked-by: Ming Lei <ming.lei@canonical.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Introduce help macro to_memory_block to hide the conversion(device-->memory_block),
just clean up.

Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Settings of the form, 'line x module y +p', can fail arbitrarily due to an
uninitialized local variable. With this patch results are consistent, as
expected.

Signed-off-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

When I included the "empty" function for sysfs_create_groups() when
CONFIG_SYSFS=n, I forgot to return a value for it, so things blew up the
build.  This patch fixes that, stupid me.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 15b0beaa ("Add x64 support to debugfs") added
debugfs_create_x64(), but forgot to provide it when debugfs is
disabled, causing problems when code tries to use it even then.
Provide the appropriate static inline.

Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The bus_attrs field of struct bus_type is going away soon, dev_groups
should be used instead.  This converts the RBD bus code to use the
correct field.

Cc: Yehuda Sadeh <yehuda@inktank.com>
Cc: Sage Weil <sage@inktank.com>
Acked-by: Alex Elder <elder@linaro.org>
Cc: <ceph-devel@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The dcdbas code was "hand rolling" a binary attribute group, which the
driver core now supports automatically.  So remove the "create the files
by hand" logic, and just set the proper field in the attribute group
structure, saving lots of code and headache.

Cc: Doug Warzecha <Douglas_Warzecha@dell.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

--

 Doug, I can take this through my driver-core tree if you don't object.

 drivers/firmware/dcdbas.c |   19 ++-----------------
 1 file changed, 2 insertions(+), 17 deletions(-)

We need these functions for when CONFIG_SYSFS=n.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This is needed to fix the build on sh systems.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The dev_attrs field of struct bus_type is going away soon, dev_groups
should be used instead.  This converts the HID bus code to use
the correct field.

Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The drv_attrs field of struct bus_type is going away soon, drv_groups
should be used instead.  This converts the serio bus code to use the
correct field.

Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The drv_attrs field of struct bus_type is going away soon, drv_groups
should be used instead.  This converts the gameport bus code to use the
correct field.

Acked: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Use __ATTR_RW() instead of __ATTR() to make it more obvious what the
type of attribute is being created.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Use DEVICE_ATTR_RO() instead of a "raw" __ATTR macro, making it easier
to audit exactly what is going on with the sysfs files.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

There are two bus attributes that can better be defined using
DRIVER_ATTR_WO(), so convert them to the new macro, making it easier to
audit attribute permissions.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This creates the macros DRIVER_ATTR_WO() and DEVICE_ATTR_WO() for
write-only attributes for drivers and devices.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This creates the macro __ATTR_WO() for write-only attributes, instead of
having to "open define" them.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The dev_attrs field of struct bus_type is going away soon, dev_groups
should be used instead.  This converts the platform bus code to use
the correct field.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The dev_attrs field of struct bus_type is going away soon, dev_groups
should be used instead.  This converts the workqueue bus code to use
the correct field.

Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The dev_attrs field of struct bus_type is going away soon, dev_groups
should be used instead.  This converts the MEI bus code to use
the correct field.

Acked-by: Tomas Winkler <tomas.winkler@intel.com>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The drv_attrs field of struct bus_type is going away soon, drv_groups
should be used instead.  This converts the USB serial bus code to use
the correct field.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 40b31360 ("Finally eradicate
CONFIG_HOTPLUG") removed remaining references to CONFIG_HOTPLUG, but missed
a few plain English references in the CONFIG_KEXEC help texts.

Remove them, too.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Cc: Mariusz Bialonczyk <manio@skyboo.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Jean-Francois Dagenais <jeff.dagenais@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: David Stevenson <david@avoncliff.com>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Cc: Michael Arndt <michael@scriptkiller.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This lets w1 slave drivers declare an attribute group, and not have to
create/destroy sysfs files directly.  All w1 slave drivers will be fixed
to use this field up in follow-on patches to this one.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

As we have 2 sysfs files for the w1 slave devices, let the driver core
create / destroy them automatically by setting the default attribute
group for them, saving code and housekeeping logic.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

W1 slave sysfs files are created _after_ userspace is notified that the
device has been added to the system.  Fix that race by moving the
creation/remove of the files to the bus notifier that is there for doing
this type of thing.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Gotta love a macro that doesn't reduce the typing you have to do.

Also, only the driver core, and one network driver uses this.  The
driver core functions will be going away soon, and I'll convert the
network driver soon to not need this as well, so delete it for now
before anyone else gets some bright ideas and wants to use it.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Fix up the wording of sysfs_create/remove_groups() a bit.

Reported-by: Anthony Foiani <tkil@scrye.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

No need to call sysfs_bin_attr_init, as the attribute is not dynamically
created.  Also, we renamed the attribute, so this one isn't even valid
anymore.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Len Brown <lenb@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

As long as we are cleaning up sysfs coding style issues, don't forget
the main sysfs.h file, so fix up the space issues there as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This fixes up the remaining coding style issues in sysfs.h

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>