The recent fix to use kstrdup_const() failed to add a
kfree upon failure of name allocation...

Cc: Ming Lei <ming.lei@canonical.com>
Cc: Seth Forshee <seth.forshee@canonical.com>
Cc: Kyle McMartin <kyle@kernel.org>
Signed-off-by: NLuis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If count == 0 bytes are requested by a reader, sysfs_kf_bin_read()
deliberately returns 0 without passing a potentially harmful value to
some externally defined underlying battr->read() function.

However in case of (pos == size && count) the next clause always sets
count to 0 and this value is handed over to battr->read().

The change intends to make obsolete (and remove later) a redundant
sanity check in battr->read(), if it is present, or add more
protection to struct bin_attribute users, who does not care about
input arguments.
Signed-off-by: NVladimir Zapolskiy <vz@mleia.com>
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: NShailendra Verma <shailendra.capricorn@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Failure path of platform_device_add was almost the same as
platform_device_del. Refactor same code in a function.
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NRicardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

of_platform_device_create_pdata() was using of_device_add() to create
the devices, but of_platform_device_destroy was using
platform_device_unregister() to free them.

of_device_add(), do not call insert_resource(), which initializes the
parent field of the resource structure, needed by release_resource(),
called by of_platform_device_destroy(). This leads to a NULL pointer
deference.

Instead of fixing the NULL pointer deference, what could hide other bugs,
this patch, replaces of_device_add() with platform_device_data().
Signed-off-by: NRicardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

insert_resource() can fail when the resource added  overlaps
(partially or fully) with another.

Device tree and AMBA devices may contain resources that overlap, so they
could not call platform_device_add (see 02bbde78 ('Revert "of:
use platform_device_add"'))"

On the other hand, device trees are released using
platform_device_unregister(). This function calls platform_device_del(),
which calls release_resource(), that crashes when the resource has not
been added with with insert_resource. This was not an issue when the
device tree could not be modified online, but this is not the case
anymore.

This patch let the flow continue when there is an insert error, after
notifying the user with a dev_err(). r->parent is set to NULL, so
platform_device_del() knows that the resource was not added, and
therefore it should not be released.
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NRicardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

platform_device_del only checks the type of the resource in order to
call release_resource.

On the other hand, platform_device_add calls insert_resource for any
resource that has a parent.

Make both code branches balanced.
Signed-off-by: NRicardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We currently use flexible arrays with a char at the
end for the remaining internal firmware name uses.
There are two limitations with the way we use this.
Since we're using a flexible array for a string on the
struct if we wanted to use two strings it means we'd
have a disjoint means of handling the strings, one
using the flexible array, and another a char * pointer.
We're also currently not using 'const' for the string.

We wish to later extend some firmware data structures
with other string/char pointers, but we also want to be
very pedantic about const usage. Since we're going to
change things to use 'const' we might as well also address
unified way to use multiple strings on the structs.

Replace the flexible array practice for strings with
kstrdup_const() and kfree_const(), this will avoid
allocations when the vmlinux .rodata is used, and just
allocate a new proper string for us when needed. This
also means we can simplify the struct allocations by
removing the string length from the allocation size
computation, which would otherwise get even more
complicated when supporting multiple strings.

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Seth Forshee <seth.forshee@canonical.com>
Cc: Kyle McMartin <kyle@kernel.org>
Signed-off-by: NLuis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Asynchronous firmware loading copies the pointer to the
name passed as an argument only to be scheduled later and
used. This behaviour works well for synchronous calling
but in asynchronous mode there's a chance the caller could
immediately free the passed string after making the
asynchronous call. This could trigger a use after free
having the kernel look on disk for arbitrary file names.

In order to force-test the issue you can use a test-driver
designed to illustrate this issue on github [0], use the
next-20150505-fix-use-after-free branch.

With this patch applied you get:

[  283.512445] firmware name: test_module_stuff.bin
[  287.514020] firmware name: test_module_stuff.bin
[  287.532489] firmware found

Without this patch applied you can end up with something such as:

[  135.624216] firmware name: \xffffff80BJ
[  135.624249] platform fake-dev.0: Direct firmware load for \xffffff80Bi failed with error -2
[  135.624252] No firmware found
[  135.624252] firmware found

Unfortunatley in the worst and most common case however you
can typically crash your system with a page fault by trying to
free something which you cannot, and/or a NULL pointer
dereference [1].

The fix and issue using schedule_work() for asynchronous
runs is generalized in the following SmPL grammar patch,
when applied to next-20150505 only the firmware_class
code is affected. This grammar patch can and should further
be generalized to vet for for other kernel asynchronous
mechanisms.

@ calls_schedule_work @
type T;
T *priv_work;
identifier func, work_func;
identifier work;
identifier priv_name, name;
expression gfp;
@@

 func(..., const char *name, ...)
 {
 	...
 	priv_work = kzalloc(sizeof(T), gfp);
 	...
-	priv_work->priv_name = name;
+	priv_work->priv_name = kstrdup_const(name, gfp);
	...
(... when any
 	if (...)
 	{
 		...
+ 		kfree_const(priv_work->priv_name);
 		kfree(priv_work);
		...
 	}
) ... when any
 	INIT_WORK(&priv_work->work, work_func);
 	...
 	schedule_work(&priv_work->work);
 	...
 }

@ the_work_func depends on calls_schedule_work @
type calls_schedule_work.T;
T *priv_work;
identifier calls_schedule_work.work_func;
identifier calls_schedule_work.priv_name;
identifier calls_schedule_work.work;
identifier some_work;
@@

 work_func(...)
 {
 	...
 	priv_work = container_of(some_work, T, work);
 	...
+	kfree_const(priv_work->priv_name);
 	kfree(priv_work);
 	...
 }

[0] https://github.com/mcgrof/fake-firmware-test.git
[1] The following kernel ring buffer splat:

firmware name: test_module_stuff.bin
firmware name:
firmware found
general protection fault: 0000 [#1] SMP
Modules linked in: test(O) <...etc-it-does-not-matter>
 drm sr_mod cdrom xhci_pci xhci_hcd rtsx_pci mfd_core video button sg
CPU: 3 PID: 87 Comm: kworker/3:2 Tainted: G           O    4.0.0-00010-g22b5bb0-dirty #176
Hardware name: LENOVO 20AW000LUS/20AW000LUS, BIOS GLET43WW (1.18 ) 12/04/2013
Workqueue: events request_firmware_work_func
task: ffff8800c7f8e290 ti: ffff8800c7f94000 task.ti: ffff8800c7f94000
RIP: 0010:[<ffffffff814a586c>]  [<ffffffff814a586c>] fw_free_buf+0xc/0x40
RSP: 0000:ffff8800c7f97d78  EFLAGS: 00010286
RAX: ffffffff81ae3700 RBX: ffffffff816d1181 RCX: 0000000000000006
RDX: 0001ee850ff68500 RSI: 0000000000000246 RDI: c35d5f415e415d41
RBP: ffff8800c7f97d88 R08: 000000000000000a R09: 0000000000000000
R10: 0000000000000358 R11: ffff8800c7f97a7e R12: ffff8800c7ec1e80
R13: ffff88021e2d4cc0 R14: ffff88021e2dff00 R15: 00000000000000c0
FS:  0000000000000000(0000) GS:ffff88021e2c0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000034b8cd8 CR3: 000000021073c000 CR4: 00000000001407e0
Stack:
 ffffffff816d1181 ffff8800c7ec1e80 ffff8800c7f97da8 ffffffff814a58f8
 000000000000000a ffffffff816d1181 ffff8800c7f97dc8 ffffffffa047002c
 ffff88021e2dff00 ffff8802116ac1c0 ffff8800c7f97df8 ffffffff814a65fe
Call Trace:
 [<ffffffff816d1181>] ? __schedule+0x361/0x940
 [<ffffffff814a58f8>] release_firmware+0x58/0x80
 [<ffffffff816d1181>] ? __schedule+0x361/0x940
 [<ffffffffa047002c>] test_mod_cb+0x2c/0x43 [test]
 [<ffffffff814a65fe>] request_firmware_work_func+0x5e/0x80
 [<ffffffff816d1181>] ? __schedule+0x361/0x940
 [<ffffffff8108d23a>] process_one_work+0x14a/0x3f0
 [<ffffffff8108d911>] worker_thread+0x121/0x460
 [<ffffffff8108d7f0>] ? rescuer_thread+0x310/0x310
 [<ffffffff810928f9>] kthread+0xc9/0xe0
 [<ffffffff81092830>] ? kthread_create_on_node+0x180/0x180
 [<ffffffff816d52d8>] ret_from_fork+0x58/0x90
 [<ffffffff81092830>] ? kthread_create_on_node+0x180/0x180
Code: c7 c6 dd ad a3 81 48 c7 c7 20 97 ce 81 31 c0 e8 0b b2 ed ff e9 78 ff ff ff 66 0f 1f 44 00 00 0f 1f 44 00 00 55 48 89 e5 41 54 53 <4c> 8b 67 38 48 89 fb 4c 89 e7 e8 85 f7 22 00 f0 83 2b 01 74 0f
RIP  [<ffffffff814a586c>] fw_free_buf+0xc/0x40
 RSP <ffff8800c7f97d78>
---[ end trace 4e62c56a58d0eac1 ]---
BUG: unable to handle kernel paging request at ffffffffffffffd8
IP: [<ffffffff81093ee0>] kthread_data+0x10/0x20
PGD 1c13067 PUD 1c15067 PMD 0
Oops: 0000 [#2] SMP
Modules linked in: test(O) <...etc-it-does-not-matter>
 drm sr_mod cdrom xhci_pci xhci_hcd rtsx_pci mfd_core video button sg
CPU: 3 PID: 87 Comm: kworker/3:2 Tainted: G      D    O    4.0.0-00010-g22b5bb0-dirty #176
Hardware name: LENOVO 20AW000LUS/20AW000LUS, BIOS GLET43WW (1.18 ) 12/04/2013
task: ffff8800c7f8e290 ti: ffff8800c7f94000 task.ti: ffff8800c7f94000
RIP: 0010:[<ffffffff81092ee0>]  [<ffffffff81092ee0>] kthread_data+0x10/0x20
RSP: 0018:ffff8800c7f97b18  EFLAGS: 00010096
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 000000000000000d
RDX: 0000000000000003 RSI: 0000000000000003 RDI: ffff8800c7f8e290
RBP: ffff8800c7f97b18 R08: 000000000000bc00 R09: 0000000000007e76
R10: 0000000000000001 R11: 000000000000002f R12: ffff8800c7f8e290
R13: 00000000000154c0 R14: 0000000000000003 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88021e2c0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000028 CR3: 0000000210675000 CR4: 00000000001407e0
Stack:
 ffff8800c7f97b38 ffffffff8108dcd5 ffff8800c7f97b38 ffff88021e2d54c0
 ffff8800c7f97b88 ffffffff816d1500 ffff880213d42368 ffff8800c7f8e290
 ffff8800c7f97b88 ffff8800c7f97fd8 ffff8800c7f8e710 0000000000000246
Call Trace:
 [<ffffffff8108dcd5>] wq_worker_sleeping+0x15/0xa0
 [<ffffffff816d1500>] __schedule+0x6e0/0x940
 [<ffffffff816d1797>] schedule+0x37/0x90
 [<ffffffff810779bc>] do_exit+0x6bc/0xb40
 [<ffffffff8101898f>] oops_end+0x9f/0xe0
 [<ffffffff81018efb>] die+0x4b/0x70
 [<ffffffff81015622>] do_general_protection+0xe2/0x170
 [<ffffffff816d74e8>] general_protection+0x28/0x30
 [<ffffffff816d1181>] ? __schedule+0x361/0x940
 [<ffffffff814a586c>] ? fw_free_buf+0xc/0x40
 [<ffffffff816d1181>] ? __schedule+0x361/0x940
 [<ffffffff814a58f8>] release_firmware+0x58/0x80
 [<ffffffff816d1181>] ? __schedule+0x361/0x940
 [<ffffffffa047002c>] test_mod_cb+0x2c/0x43 [test]
 [<ffffffff814a65fe>] request_firmware_work_func+0x5e/0x80
 [<ffffffff816d1181>] ? __schedule+0x361/0x940
 [<ffffffff8108d23a>] process_one_work+0x14a/0x3f0
 [<ffffffff8108d911>] worker_thread+0x121/0x460
 [<ffffffff8108d7f0>] ? rescuer_thread+0x310/0x310
 [<ffffffff810928f9>] kthread+0xc9/0xe0
 [<ffffffff81092830>] ? kthread_create_on_node+0x180/0x180
 [<ffffffff816d52d8>] ret_from_fork+0x58/0x90
 [<ffffffff81092830>] ? kthread_create_on_node+0x180/0x180
Code: 00 48 89 e5 5d 48 8b 40 c8 48 c1 e8 02 83 e0 01 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 8b 87 30 05 00 00 55 48 89 e5 <48> 8b 40 d8 5d c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00
RIP  [<ffffffff81092ee0>] kthread_data+0x10/0x20
 RSP <ffff8800c7f97b18>
CR2: ffffffffffffffd8
---[ end trace 4e62c56a58d0eac2 ]---
Fixing recursive fault but reboot is needed!

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Seth Forshee <seth.forshee@canonical.com>
Cc: Kyle McMartin <kyle@kernel.org>
Generated-by: Coccinelle SmPL
Signed-off-by: NLuis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When direct firmware loading is used we iterate over a list
of possible firmware paths and concatenate the desired firmware
name with each path and look for the file there. Should the
passed firmware name be too long we end up truncating the
file we want to look for, the search however is still done.
Add a check for truncation instead of looking for a
truncated firmware filename.

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@kernel.org>
Signed-off-by: NLuis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The request_firmware*() APIs uses __getname() to iterate
over the list of paths possible for firmware to be found,
the code however never checked for failure on __getname().
Although *very unlikely*, this can still happen. Add the
missing check.

There is still no checks on the concatenation of the path
and filename passed, that requires a bit more work and
subsequent patches address this. The commit that introduced
this is abb139e7 ("firmware: teach the kernel to load
firmware files directly from the filesystem").

mcgrof@ergon ~/linux (git::firmware-fixes) $ git describe --contains abb139e7
v3.7-rc1~120

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@kernel.org>
Signed-off-by: NLuis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit 5590f319 ("drivers/core/of: Add symlink to device-tree from
devices with an OF node") adds the symlink `of_node` for each device
pointing to it's device tree node while creating/initialising it.

However the devicetree sysfs is created and setup in of_init which is
executed at core_initcall level. For all the devices created before
of_init, the following error is thrown:
	"Error -2(-ENOENT) creating of_node link"

Like many other components in driver model, initialize the sysfs support
for OF/devicetree from driver_init so that it's ready before any devices
are created.

Fixes: 5590f319 ("drivers/core/of: Add symlink to device-tree from
	devices with an OF node")
Suggested-by: NRob Herring <robh+dt@kernel.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>
Tested-by: NRobert Schwebel <r.schwebel@pengutronix.de>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

s/hierarcy/hierarchy/

Maybe the typo will annoy people enough so that they add the missing
nodes to their device-tree files, but I still think this is better off
fixed.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NSudeep Holla <sudeep.holla@arm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The sentence "Returns 0 on success or error" might be misinterpreted as
"the function will always returns 0", make it less ambiguous.

Also, use the word "failure" as the contrary of "success".
Signed-off-by: NAntonio Ospite <ao2@ao2.it>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit f2411da7 ("driver-core: add driver module asynchronous probe
support") broke build in case modules are disabled, because in this case
"struct module" is not defined and we can't dereference it. Let's define
module_requested_async_probing() helper and stub it out if modules are
disabled.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

It is only used within dd.c and thus need not be global.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

My kernfs patch slipped through because I didn't know which maintainer
to CC. Have been told it's gkh. Add an entry, and sort the file patterns
while we are here.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Grabbing the parent is not happening anymore since 2010 (e72ceb8c
"sysfs: Remove sysfs_get/put_active_two"). Remove this confusing
comment.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Similarly to module_param_unsafe(), add the helper to be used by core
code wishing to expose unsafe debugging or testing parameters that taint
the kernel when set.
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

While testing asynchronous PCI probe on this driver I noticed it failed
because the driver checks if any of the PCI devices have been bound to
the driver after registering it, which obviously does not work if
probing is asynchronous.

While there are patches and discussions on how the driver should behave
are ongoing, let's enforce synchronous probe for this driver for now.
Reviewed-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NLuis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Because platform_driver_probe() checks, after trying to register driver,
if there are any devices that driver successfully bound to, driver's
probe routine must be run synchronously.
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There are drivers that can not be probed asynchronously. One such group
is platform drivers registered with platform_driver_probe(), which
expects driver's probe routine be discarded after the driver has been
registered and initial binding attempt executed. Also
platform_driver_probe() an error when no devices were bound to the
driver, allowing failing to load such driver module altogether.

Other drivers do not work well with asynchronous probing because of
driver bug or not optimal driver organization.

To allow using such drivers even when user requests asynchronous probing
as default boot strategy, let's allow them to opt out.
Signed-off-by: NLuis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Some init systems may wish to express the desire to have device drivers
run their probe() code asynchronously. This implements support for this
and allows userspace to request async probe as a preference through a
generic shared device driver module parameter, async_probe.

Implementation for async probe is supported through a module parameter
given that since synchronous probe has been prevalent for years some
userspace might exist which relies on the fact that the device driver
will probe synchronously and the assumption that devices it provides
will be immediately available after this.
Signed-off-by: NLuis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Some devices take a long time when initializing, and not all drivers are
suited to initialize their devices when they are open. For example,
input drivers need to interrogate their devices in order to publish
device's capabilities before userspace will open them. When such drivers
are compiled into kernel they may stall entire kernel initialization.

This change allows drivers request for their probe functions to be
called asynchronously during driver and device registration (manual
binding is still synchronous). Because async_schedule is used to perform
asynchronous calls module loading will still wait for the probing to
complete.

Note that the end goal is to make the probing asynchronous by default,
so annotating drivers with PROBE_PREFER_ASYNCHRONOUS is a temporary
measure that allows us to speed up boot process while we validating and
fixing the rest of the drivers and preparing userspace.

This change is based on earlier patch by "Luis R. Rodriguez"
<mcgrof@suse.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This adds an extra argument onto parse_params() to be used
as a way to make the unused callback a bit more useful and
generic by allowing the caller to pass on a data structure
of its choice. An example use case is to allow us to easily
make module parameters for every module which we will do
next.

@ parse @
identifier name, args, params, num, level_min, level_max;
identifier unknown, param, val, doing;
type s16;
@@
 extern char *parse_args(const char *name,
 			 char *args,
 			 const struct kernel_param *params,
 			 unsigned num,
 			 s16 level_min,
 			 s16 level_max,
+			 void *arg,
 			 int (*unknown)(char *param, char *val,
					const char *doing
+					, void *arg
					));

@ parse_mod @
identifier name, args, params, num, level_min, level_max;
identifier unknown, param, val, doing;
type s16;
@@
 char *parse_args(const char *name,
 			 char *args,
 			 const struct kernel_param *params,
 			 unsigned num,
 			 s16 level_min,
 			 s16 level_max,
+			 void *arg,
 			 int (*unknown)(char *param, char *val,
					const char *doing
+					, void *arg
					))
{
	...
}

@ parse_args_found @
expression R, E1, E2, E3, E4, E5, E6;
identifier func;
@@

(
	R =
	parse_args(E1, E2, E3, E4, E5, E6,
+		   NULL,
		   func);
|
	R =
	parse_args(E1, E2, E3, E4, E5, E6,
+		   NULL,
		   &func);
|
	R =
	parse_args(E1, E2, E3, E4, E5, E6,
+		   NULL,
		   NULL);
|
	parse_args(E1, E2, E3, E4, E5, E6,
+		   NULL,
		   func);
|
	parse_args(E1, E2, E3, E4, E5, E6,
+		   NULL,
		   &func);
|
	parse_args(E1, E2, E3, E4, E5, E6,
+		   NULL,
		   NULL);
)

@ parse_args_unused depends on parse_args_found @
identifier parse_args_found.func;
@@

int func(char *param, char *val, const char *unused
+		 , void *arg
		 )
{
	...
}

@ mod_unused depends on parse_args_found @
identifier parse_args_found.func;
expression A1, A2, A3;
@@

-	func(A1, A2, A3);
+	func(A1, A2, A3, NULL);

Generated-by: Coccinelle SmPL
Cc: cocci@systeme.lip6.fr
Cc: Tejun Heo <tj@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Felipe Contreras <felipe.contreras@gmail.com>
Cc: Ewan Milne <emilne@redhat.com>
Cc: Jean Delvare <jdelvare@suse.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: linux-kernel@vger.kernel.org
Reviewed-by: NTejun Heo <tj@kernel.org>
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NLuis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Currently there is no way to query which CPUs are in nohz_full
mode from userspace.

Export the CPU list running in nohz_full mode in sysfs,
specifically in the file /sys/devices/system/cpu/nohz_full

This can be used by system management tools like libvirt,
openstack, and others to ensure proper task placement.
Signed-off-by: NRik van Riel <riel@redhat.com>
Acked-by: NMike Galbraith <umgwanakikbuti@gmail.com>
Acked-by: NChris Metcalf <cmetcalf@ezchip.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

After system bootup, there is no totally reliable way to see
which CPUs are isolated, because the kernel may modify the
CPUs specified on the isolcpus= kernel command line option.

Export the CPU list that actually got isolated in sysfs,
specifically in the file /sys/devices/system/cpu/isolated

This can be used by system management tools like libvirt,
openstack, and others to ensure proper placement of tasks.
Suggested-by: NLi Zefan <lizefan@huawei.com>
Signed-off-by: NRik van Riel <riel@redhat.com>
Acked-by: NMike Galbraith <umgwanakikbuti@gmail.com>
Acked-by: NChris Metcalf <cmetcalf@ezchip.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Two watchdog changes that came through different trees had a non
conflicting conflict, that is, one changed the semantics of a variable
but no actual code conflict happened. So the merge appeared fine, but
the resulting code did not behave as expected.

Commit 195daf66 ("watchdog: enable the new user interface of the
watchdog mechanism") changes the semantics of watchdog_user_enabled,
which thereafter is only used by the functions introduced by
b3738d29 ("watchdog: Add watchdog enable/disable all functions").

There further appears to be a distinct lack of serialization between
setting and using watchdog_enabled, so perhaps we should wrap the
{en,dis}able_all() things in watchdog_proc_mutex.

This patch fixes a s2r failure reported by Michal; which I cannot
readily explain. But this does make the code internally consistent
again.
Reported-and-tested-by: NMichal Hocko <mhocko@suse.cz>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull MTD fixes from Brian Norris:
 "Two MTD fixes for 4.1:

   - readtest: the signal-handling code was clobbering the error codes
     we should be handling/reporting in this test, rendering it useless.
     Noticed by Coverity.

   - the common SPI NOR flash DT binding (merged for 4.1-rc1) is being
     revised, so let's change that before 4.1 is minted"

* tag 'for-linus-20150516' of git://git.infradead.org/linux-mtd:
  Documentation: dt: mtd: replace "nor-jedec" binding with "jedec, spi-nor"
  mtd: readtest: don't clobber error reports

Pull USB fixes from Greg KH:
 "Here are some USB fixes and new device ids for 4.1-rc4.

  All are pretty minor, and have been in linux-next successfully"

* tag 'usb-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb-storage: Add NO_WP_DETECT quirk for Lacie 059f:0651 devices
  Added another USB product ID for ELAN touchscreen quirks.
  xhci: gracefully handle xhci_irq dead device
  xhci: Solve full event ring by increasing TRBS_PER_SEGMENT to 256
  xhci: fix isoc endpoint dequeue from advancing too far on transaction error
  usb: chipidea: debug: avoid out of bound read
  USB: visor: Match I330 phone more precisely
  USB: pl2303: Remove support for Samsung I330
  USB: cp210x: add ID for KCF Technologies PRN device
  usb: gadget: remove incorrect __init/__exit annotations
  usb: phy: isp1301: work around tps65010 dependency
  usb: gadget: serial: fix re-ordering of tx data
  usb: gadget: hid: Fix static variable usage
  usb: gadget: configfs: Fix interfaces array NULL-termination
  usb: gadget: xilinx: fix devm_ioremap_resource() check
  usb: dwc3: dwc3-omap: correct the register macros

Pull tty/serial fixes from Greg KH:
 "Here's some TTY and serial driver fixes for reported issues.

  All of these have been in linux-next successfully"

* tag 'tty-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  pty: Fix input race when closing
  tty/n_gsm.c: fix a memory leak when gsmtty is removed
  Revert "serial/amba-pl011: Leave the TX IRQ alone when the UART is not open"
  serial: omap: Fix error handling in probe
  earlycon: Revert log warnings

Pull staging / IIO driver fixes from Greg KH:
 "Here's some staging and iio driver fixes to resolve a number of
  reported issues.

  All of these have been in linux-next for a while"

* tag 'staging-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (31 commits)
  iio: light: hid-sensor-prox: Fix memory leak in probe()
  iio: adc: cc10001: Add delay before setting START bit
  iio: adc: cc10001: Fix regulator_get_voltage() return value check
  iio: adc: cc10001: Fix incorrect use of power-up/power-down register
  staging: gdm724x: Correction of variable usage after applying ALIGN()
  iio: adc: cc10001: Fix the channel number mapping
  staging: vt6655: lock MACvWriteBSSIDAddress.
  staging: vt6655: CARDbUpdateTSF bss timestamp correct tsf counter value.
  staging: vt6655: vnt_tx_packet Correct TX order of OWNED_BY_NIC
  staging: vt6655: Fix 80211 control and management status reporting.
  staging: vt6655: implement IEEE80211_TX_STAT_NOACK_TRANSMITTED
  staging: vt6655: device_free_tx_buf use only ieee80211_tx_status_irqsafe
  staging: vt6656: use ieee80211_tx_info to select packet type.
  staging: rtl8712: freeing an ERR_PTR
  staging: sm750: remove incorrect __exit annotation
  iio: kfifo: Set update_needed to false only if a buffer was allocated
  iio: mcp320x: Fix occasional incorrect readings
  iio: accel: mma9553: check input value for activity period
  iio: accel: mma9553: add enable channel for activity
  iio: accel: mma9551_core: prevent buffer overrun
  ...

Pull char/misc fix from Greg KH:
 "Here is one fix, in the extcon subsystem, that resolves a reported
  issue.

  It's been in linux-next for a number of weeks now, sorry for not
  getting it to you sooner"

* tag 'char-misc-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  extcon: usb-gpio: register extcon device before IRQ registration

Pull UML hostfs fix from Richard Weinberger:
 "This contains a single fix for a regression introduced in 4.1-rc1"

* 'for-linus-4.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  hostfs: Use correct mask for file mode

Pull UBI bufix from Richard Weinberger:
 "This contains a single bug fix for the UBI block driver"

* tag 'upstream-4.1-rc4' of git://git.infradead.org/linux-ubifs:
  UBI: block: Add missing cache flushes

Pull ext4 fixes from Ted Ts'o:
 "Fix a number of ext4 bugs; the most serious of which is a bug in the
  lazytime mount optimization code where we could end up updating the
  timestamps to the wrong inode"

* tag 'for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix an ext3 collapse range regression in xfstests
  jbd2: fix r_count overflows leading to buffer overflow in journal recovery
  ext4: check for zero length extent explicitly
  ext4: fix NULL pointer dereference when journal restart fails
  ext4: remove unused function prototype from ext4.h
  ext4: don't save the error information if the block device is read-only
  ext4: fix lazytime optimization

Pull btrfs fixes from Chris Mason:
 "The first commit is a fix from Filipe for a very old extent buffer
  reuse race that triggered a BUG_ON.  It hasn't come up often, I looked
  through old logs at FB and we hit it a handful of times over the last
  year.

  The rest are other corners he hit during testing"

* 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix race when reusing stale extent buffers that leads to BUG_ON
  Btrfs: fix race between block group creation and their cache writeout
  Btrfs: fix panic when starting bg cache writeout after IO error
  Btrfs: fix crash after inode cache writeback failure

Pull MIPS fixes from Ralf Baechle:
 "Seven small fixes.  The shortlog below is a good description so no
  need to elaborate.

  It has sat in linux-next and survived the usual automated testing by
  Imagination's test farm"

* 'master' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: tlb-r4k: Fix PG_ELPA comment
  MIPS: Fix up obsolete cpu_set usage
  MIPS: IP32: Fix build errors in reset code in DS1685 platform hook.
  MIPS: KVM: Fix unused variable build warning
  MIPS: traps: remove extra Tainted: line from __show_regs() output
  MIPS: Fix wrong CHECKFLAGS (sparse builds) with GCC 5.1
  MIPS: Fix a preemption issue with thread's FPU defaults

Pull ARC fixes from Vineet Gupta.

* tag 'arc-4.1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: inline cache flush toggle helpers
  ARC: With earlycon in use, retire EARLY_PRINTK
  ARC: unbork !LLSC build