powerpc, workqueue: Use alloc_ordered_workqueue() to create ordered workqueues

BACKGROUND
==========

When multiple work items are queued to a workqueue, their execution order
doesn't match the queu

powerpc, workqueue: Use alloc_ordered_workqueue() to create ordered workqueues

BACKGROUND
==========

When multiple work items are queued to a workqueue, their execution order
doesn't match the queueing order. They may get executed in any order and
simultaneously. When fully serialized execution - one by one in the queueing
order - is needed, an ordered workqueue should be used which can be created
with alloc_ordered_workqueue().

However, alloc_ordered_workqueue() was a later addition. Before it, an
ordered workqueue could be obtained by creating an UNBOUND workqueue with
@max_active==1. This originally was an implementation side-effect which was
broken by 4c16bd327c74 ("workqueue: restore WQ_UNBOUND/max_active==1 to be
ordered"). Because there were users that depended on the ordered execution,
5c0338c68706 ("workqueue: restore WQ_UNBOUND/max_active==1 to be ordered")
made workqueue allocation path to implicitly promote UNBOUND workqueues w/
@max_active==1 to ordered workqueues.

While this has worked okay, overloading the UNBOUND allocation interface
this way creates other issues. It's difficult to tell whether a given
workqueue actually needs to be ordered and users that legitimately want a
min concurrency level wq unexpectedly gets an ordered one instead. With
planned UNBOUND workqueue updates to improve execution locality and more
prevalence of chiplet designs which can benefit from such improvements, this
isn't a state we wanna be in forever.

This patch series audits all callsites that create an UNBOUND workqueue w/
@max_active==1 and converts them to alloc_ordered_workqueue() as necessary.

WHAT TO LOOK FOR
================

The conversions are from

alloc_workqueue(WQ_UNBOUND | flags, 1, args..)

to

alloc_ordered_workqueue(flags, args...)

which don't cause any functional changes. If you know that fully ordered
execution is not ncessary, please let me know. I'll drop the conversion and
instead add a comment noting the fact to reduce confusion while conversion
is in progress.

If you aren't fully sure, it's completely fine to let the conversion
through. The behavior will stay exactly the same and we can always
reconsider later.

As there are follow-up workqueue core changes, I'd really appreciate if the
patch can be routed through the workqueue tree w/ your acks. Thanks.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Nathan Lynch <nathanl@linux.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org

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driver core: class: mark the struct class for sysfs callbacks as constant

struct class should never be modified in a sysfs callback as there is
nothing in the structure to modify, and frankly, the s

driver core: class: mark the struct class for sysfs callbacks as constant

struct class should never be modified in a sysfs callback as there is
nothing in the structure to modify, and frankly, the structure is almost
never used in a sysfs callback, so mark it as constant to allow struct
class to be moved to read-only memory.

While we are touching all class sysfs callbacks also mark the attribute
as constant as it can not be modified. The bonding code still uses this
structure so it can not be removed from the function callbacks.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Bartosz Golaszewski <brgl@bgdev.pl>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Russ Weight <russell.h.weight@intel.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Steve French <sfrench@samba.org>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Cc: linux-cifs@vger.kernel.org
Cc: linux-gpio@vger.kernel.org
Cc: linux-mtd@lists.infradead.org
Cc: linux-rdma@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: netdev@vger.kernel.org
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20230325084537.3622280-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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powerpc/rtas: arch-wide function token lookup conversions

With the tokens for all implemented RTAS functions now available via
rtas_function_token(), which is optimal and safe for arbitrary
contexts

powerpc/rtas: arch-wide function token lookup conversions

With the tokens for all implemented RTAS functions now available via
rtas_function_token(), which is optimal and safe for arbitrary
contexts, there is no need to use rtas_token() or cache its result.

Most conversions are trivial, but a few are worth describing in more
detail:

* Error injection token comparisons for lockdown purposes are
consolidated into a simple predicate: token_is_restricted_errinjct().

* A couple of special cases in block_rtas_call() do not use
rtas_token() but perform string comparisons against names in the
function table. These are converted to compare against token values
instead, which is logically equivalent but less expensive.

* The lookup for the ibm,os-term token can be deferred until needed,
instead of caching it at boot to avoid device tree traversal during
panic.

* Since rtas_function_token() accesses a read-only data structure
without taking any locks, xmon's lookup of set-indicator can be
performed as needed instead of cached at startup.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230125-b4-powerpc-rtas-queue-v3-20-26929c8cce78@linux.ibm.com

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powerpc/pseries/dlpar: use RTAS work area API

Hold a work area object for the duration of the RTAS
ibm,configure-connector sequence, eliminating locking and copying
around each RTAS call.

Signed-of

powerpc/pseries/dlpar: use RTAS work area API

Hold a work area object for the duration of the RTAS
ibm,configure-connector sequence, eliminating locking and copying
around each RTAS call.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230125-b4-powerpc-rtas-queue-v3-13-26929c8cce78@linux.ibm.com

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powerpc: Remove asm/prom.h from all files that don't need it

Several files include asm/prom.h for no reason.

Clean it up.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Drop c

powerpc: Remove asm/prom.h from all files that don't need it

Several files include asm/prom.h for no reason.

Clean it up.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Drop change to prom_parse.c as reported by lkp@intel.com]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7c9b8fda63dcf63e1b28f43e7ebdb95182cbc286.1646767214.git.christophe.leroy@csgroup.eu

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powerpc/pseries/dlpar: Remove unnecessary cast to kfree()

Remove unnecassary cast in the argument to kfree().

Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Signed-off-by: Christophe Leroy <christophe.

powerpc/pseries/dlpar: Remove unnecessary cast to kfree()

Remove unnecassary cast in the argument to kfree().

Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200708072228.30776-1-vulab@iscas.ac.cn

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powerpc/pseries/dlpar: use rtas_get_sensor()

Instead of making bare calls to get-sensor-state, use
rtas_get_sensor(), which correctly handles busy and extended delay
statuses.

Fixes: ab519a011caa (

powerpc/pseries/dlpar: use rtas_get_sensor()

Instead of making bare calls to get-sensor-state, use
rtas_get_sensor(), which correctly handles busy and extended delay
statuses.

Fixes: ab519a011caa ("powerpc/pseries: Kernel DLPAR Infrastructure")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210504025329.1713878-1-nathanl@linux.ibm.com

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powerpc/pseries: Introduce dlpar_unisolate_drc()

Next patch will execute a set-indicator call in hotplug-cpu.c.

Create a dlpar_unisolate_drc() helper to avoid spreading more
rtas_set_indicator() ca

powerpc/pseries: Introduce dlpar_unisolate_drc()

Next patch will execute a set-indicator call in hotplug-cpu.c.

Create a dlpar_unisolate_drc() helper to avoid spreading more
rtas_set_indicator() calls outside of dlpar.c.

Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210416210216.380291-2-danielhb413@gmail.com

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powerpc/pseries/dlpar: handle ibm, configure-connector delay status

dlpar_configure_connector() has two problems in its handling of
ibm,configure-connector's return status:

1. When the status is -2

powerpc/pseries/dlpar: handle ibm, configure-connector delay status

dlpar_configure_connector() has two problems in its handling of
ibm,configure-connector's return status:

1. When the status is -2 (busy, call again), we call
ibm,configure-connector again immediately without checking whether
to schedule, which can result in monopolizing the CPU.
2. Extended delay status (9900..9905) goes completely unhandled,
causing the configuration to unnecessarily terminate.

Fix both of these issues by using rtas_busy_delay().

Fixes: ab519a011caa ("powerpc/pseries: Kernel DLPAR Infrastructure")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210107025900.410369-1-nathanl@linux.ibm.com

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powerpc/pseries: Delete an error message for a failed string duplication in dlpar_store()

Omit an extra message for a memory allocation failure in this function.

Signed-off-by: Markus Elfring <elfr

powerpc/pseries: Delete an error message for a failed string duplication in dlpar_store()

Omit an extra message for a memory allocation failure in this function.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/535cfec2-782f-61ec-f6fb-c50186ead2af@web.de

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powerpc/pseries: Delete an unnecessary kfree() call in dlpar_store()

A null pointer would be passed to a call of the function “kfree”
immediately after a call of the function “kstrdup” failed at one

powerpc/pseries: Delete an unnecessary kfree() call in dlpar_store()

A null pointer would be passed to a call of the function “kfree”
immediately after a call of the function “kstrdup” failed at one place.
Remove this superfluous function call.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b46cc4ff-a14c-0c10-0c0c-95573a960178@web.de

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powerpc/pseries/dlpar: handle ibm, configure-connector delay status

[ Upstream commit 768d70e19ba525debd571b36e6d0ab19956c63d7 ]

dlpar_configure_connector() has two problems in its handling of
ibm,

powerpc/pseries/dlpar: handle ibm, configure-connector delay status

[ Upstream commit 768d70e19ba525debd571b36e6d0ab19956c63d7 ]

dlpar_configure_connector() has two problems in its handling of
ibm,configure-connector's return status:

1. When the status is -2 (busy, call again), we call
ibm,configure-connector again immediately without checking whether
to schedule, which can result in monopolizing the CPU.
2. Extended delay status (9900..9905) goes completely unhandled,
causing the configuration to unnecessarily terminate.

Fix both of these issues by using rtas_busy_delay().

Fixes: ab519a011caa ("powerpc/pseries: Kernel DLPAR Infrastructure")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210107025900.410369-1-nathanl@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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powerpc/pseries: avoid blocking in irq when queuing hotplug events

A couple of bugs in queue_hotplug_event():

1. Unchecked kmalloc result which could lead to an oops.
2. Use of GFP_KERNEL allocatio

powerpc/pseries: avoid blocking in irq when queuing hotplug events

A couple of bugs in queue_hotplug_event():

1. Unchecked kmalloc result which could lead to an oops.
2. Use of GFP_KERNEL allocations in interrupt context (this code's
only caller is ras_hotplug_interrupt()).

Use kmemdup to avoid open-coding the allocation+copy and check for
failure; use GFP_ATOMIC for both allocations.

Ultimately it probably would be better to avoid or reduce allocations
in this path if possible.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/pseries/dlpar: Fix a missing check in dlpar_parse_cc_property()

In dlpar_parse_cc_property(), 'prop->name' is allocated by kstrdup().
kstrdup() may return NULL, so it should be checked and h

powerpc/pseries/dlpar: Fix a missing check in dlpar_parse_cc_property()

In dlpar_parse_cc_property(), 'prop->name' is allocated by kstrdup().
kstrdup() may return NULL, so it should be checked and handle error.
And prop should be freed if 'prop->name' is NULL.

Signed-off-by: Gen Zhang <blackgod016574@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/pseries: add of_node_put() in dlpar_detach_node()

The previous commit, "of: overlay: add missing of_node_get() in
__of_attach_node_sysfs" added a missing of_node_get() to
__of_attach_node_sy

powerpc/pseries: add of_node_put() in dlpar_detach_node()

The previous commit, "of: overlay: add missing of_node_get() in
__of_attach_node_sysfs" added a missing of_node_get() to
__of_attach_node_sysfs(). This results in a refcount imbalance
for nodes attached with dlpar_attach_node(). The calling sequence
from dlpar_attach_node() to __of_attach_node_sysfs() is:

dlpar_attach_node()
of_attach_node()
__of_attach_node_sysfs()

For more detailed description of the node refcount, see
commit 68baf692c435 ("powerpc/pseries: Fix of_node_put() underflow
during DLPAR remove").

Tested-by: Alan Tull <atull@kernel.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Frank Rowand <frank.rowand@sony.com>

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powerpc/pseries: PAPR persistent memory support

This patch implements support for discovering storage class memory
devices at boot and for handling hotplug of new regions via RTAS
hotplug events.

S

powerpc/pseries: PAPR persistent memory support

This patch implements support for discovering storage class memory
devices at boot and for handling hotplug of new regions via RTAS
hotplug events.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
[mpe: Fix CONFIG_MEMORY_HOTPLUG=n build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/pseries: Remove unneeded uses of dlpar work queue

There are three instances in which dlpar hotplug events are invoked;
handling a hotplug interrupt (in a kvm guest), handling a dlpar
request

powerpc/pseries: Remove unneeded uses of dlpar work queue

There are three instances in which dlpar hotplug events are invoked;
handling a hotplug interrupt (in a kvm guest), handling a dlpar
request through sysfs, and updating LMB affinity when handling a
PRRN event. Only in the case of handling a hotplug interrupt do we
have to put the work on a workqueue, the other cases can handle the
dlpar request directly.

This patch exports the handle_dlpar_errorlog() function so that
dlpar hotplug events can be handled directly and updates the two
instances mentioned above to use the direct invocation.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc/pseries: Make RAS IRQ explicitly dependent on DLPAR WQ

The hotplug code uses its own workqueue to handle IRQ requests
(pseries_hp_wq), however that workqueue is initialized after
init_ras_IR

powerpc/pseries: Make RAS IRQ explicitly dependent on DLPAR WQ

The hotplug code uses its own workqueue to handle IRQ requests
(pseries_hp_wq), however that workqueue is initialized after
init_ras_IRQ(). That can lead to a kernel panic if any hotplug
interrupts fire after init_ras_IRQ() but before pseries_hp_wq is
initialised. eg:

UDP-Lite hash table entries: 2048 (order: 0, 65536 bytes)
NET: Registered protocol family 1
Unpacking initramfs...
(qemu) object_add memory-backend-ram,id=mem1,size=10G
(qemu) device_add pc-dimm,id=dimm1,memdev=mem1
Unable to handle kernel paging request for data at address 0xf94d03007c421378
Faulting instruction address: 0xc00000000012d744
Oops: Kernel access of bad area, sig: 11 [#1]
LE SMP NR_CPUS=2048 NUMA pSeries
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.15.0-rc2-ziviani+ #26
task: (ptrval) task.stack: (ptrval)
NIP: c00000000012d744 LR: c00000000012d744 CTR: 0000000000000000
REGS: (ptrval) TRAP: 0380 Not tainted (4.15.0-rc2-ziviani+)
MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 28088042 XER: 20040000
CFAR: c00000000012d3c4 SOFTE: 0
...
NIP [c00000000012d744] __queue_work+0xd4/0x5c0
LR [c00000000012d744] __queue_work+0xd4/0x5c0
Call Trace:
[c0000000fffefb90] [c00000000012d744] __queue_work+0xd4/0x5c0 (unreliable)
[c0000000fffefc70] [c00000000012dce4] queue_work_on+0xb4/0xf0

This commit makes the RAS IRQ registration explicitly dependent on the
creation of the pseries_hp_wq.

Reported-by: Min Deng <mdeng@redhat.com>
Reported-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Tested-by: Jose Ricardo Ziviani <joserz@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

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powerpc: pseries: only store the device node basename in full_name

With dependencies on full_name containing the entire device node path
removed, stop storing the full_name in nodes created by
dlpar

powerpc: pseries: only store the device node basename in full_name

With dependencies on full_name containing the entire device node path
removed, stop storing the full_name in nodes created by
dlpar_configure_connector() and pSeries_reconfig_add_node().

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org

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powerpc/pseries: Fix "OF: ERROR: Bad of_node_put() on /cpus" during DLPAR

Commit 215ee763f8cb ("powerpc: pseries: remove dlpar_attach_node
dependency on full path") reworked dlpar_attach_node() to n

powerpc/pseries: Fix "OF: ERROR: Bad of_node_put() on /cpus" during DLPAR

Commit 215ee763f8cb ("powerpc: pseries: remove dlpar_attach_node
dependency on full path") reworked dlpar_attach_node() to no longer
look up the parent node "/cpus", but instead to have the parent node
passed by the caller in the function parameter list.

As a result dlpar_attach_node() is no longer responsible for freeing
the reference to the parent node. However, commit 215ee763f8cb failed
to remove the of_node_put(parent) call in dlpar_attach_node(), or to
take into account that the reference to the parent in the caller
dlpar_cpu_add() needs to be held until after dlpar_attach_node()
returns.

As a result doing repeated cpu add/remove dlpar operations will
eventually result in the following error:

OF: ERROR: Bad of_node_put() on /cpus
CPU: 0 PID: 10896 Comm: drmgr Not tainted 4.13.0-autotest #1
Call Trace:
dump_stack+0x15c/0x1f8 (unreliable)
of_node_release+0x1a4/0x1c0
kobject_put+0x1a8/0x310
kobject_del+0xbc/0xf0
__of_detach_node_sysfs+0x144/0x210
of_detach_node+0xf0/0x180
dlpar_detach_node+0xc4/0x120
dlpar_cpu_remove+0x280/0x560
dlpar_cpu_release+0xbc/0x1b0
arch_cpu_release+0x6c/0xb0
cpu_release_store+0xa0/0x100
dev_attr_store+0x68/0xa0
sysfs_kf_write+0xa8/0xf0
kernfs_fop_write+0x2cc/0x400
__vfs_write+0x5c/0x340
vfs_write+0x1a8/0x3d0
SyS_write+0xa8/0x1a0
system_call+0x58/0x6c

Fix the issue by removing the of_node_put(parent) call from
dlpar_attach_node(), and ensuring that the reference to the parent
node is properly held and released by the caller dlpar_cpu_add().

Fixes: 215ee763f8cb ("powerpc: pseries: remove dlpar_attach_node dependency on full path")
Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
[mpe: Add a comment in the code and frob the change log slightly]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc: pseries: remove dlpar_attach_node dependency on full path

In preparation to stop storing the full node path in full_name, remove the
dependency on full_name from dlpar_attach_node(). Caller

powerpc: pseries: remove dlpar_attach_node dependency on full path

In preparation to stop storing the full node path in full_name, remove the
dependency on full_name from dlpar_attach_node(). Callers of
dlpar_attach_node() already have the parent device_node, so just pass the
parent node into dlpar_attach_node instead of the path. This avoids doing
a lookup of the parent node by the path.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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powerpc: Convert to using %pOF instead of full_name

Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the fu

powerpc: Convert to using %pOF instead of full_name

Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: Scott Wood <oss@buserror.net>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linuxppc-dev@lists.ozlabs.org
Reviewed-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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driver core: remove CLASS_ATTR usage

There was only 2 remaining users of CLASS_ATTR() so let's finally get
rid of them and force everyone to use the correct RW/RO/WO versions
instead.

Cc: Benjamin

driver core: remove CLASS_ATTR usage

There was only 2 remaining users of CLASS_ATTR() so let's finally get
rid of them and force everyone to use the correct RW/RO/WO versions
instead.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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powerpc/pseries: Fix of_node_put() underflow during DLPAR remove

Historically struct device_node references were tracked using a kref embedded as
a struct field. Commit 75b57ecf9d1d ("of: Make devic

powerpc/pseries: Fix of_node_put() underflow during DLPAR remove

Historically struct device_node references were tracked using a kref embedded as
a struct field. Commit 75b57ecf9d1d ("of: Make device nodes kobjects so they
show up in sysfs") (Mar 2014) refactored device_nodes to be kobjects such that
the device tree could by more simply exposed to userspace using sysfs.

Commit 0829f6d1f69e ("of: device_node kobject lifecycle fixes") (Mar 2014)
followed up these changes to better control the kobject lifecycle and in
particular the referecne counting via of_node_get(), of_node_put(), and
of_node_init().

A result of this second commit was that it introduced an of_node_put() call when
a dynamic node is detached, in of_node_remove(), that removes the initial kobj
reference created by of_node_init().

Traditionally as the original dynamic device node user the pseries code had
assumed responsibilty for releasing this final reference in its platform
specific DLPAR detach code.

This patch fixes a refcount underflow introduced by commit 0829f6d1f6, and
recently exposed by the upstreaming of the recount API.

Messages like the following are no longer seen in the kernel log with this
patch following DLPAR remove operations of cpus and pci devices.

rpadlpar_io: slot PHB 72 removed
refcount_t: underflow; use-after-free.
------------[ cut here ]------------
WARNING: CPU: 5 PID: 3335 at lib/refcount.c:128 refcount_sub_and_test+0xf4/0x110

Fixes: 0829f6d1f69e ("of: device_node kobject lifecycle fixes")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
[mpe: Make change log commit references more verbose]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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