linux-stable.git/include/linux/device.h, branch v6.6.140 Linux kernel stable tree driver core: Add kernel-doc for DEV_FLAG_COUNT enum value 2026-05-17T15:13:33+00:00 Douglas Anderson dianders@chromium.org 2026-04-14T02:59:11+00:00 68532b09cbfc1f362d5394d622cff44e0fbd04be commit 5b484311507b5d403c1f7a45f6aa3778549e268b upstream. Even though nobody should use this value (except when declaring the "flags" bitmap), kernel-doc still gets upset that it's not documented. It reports: WARNING: ../include/linux/device.h:519 Enum value 'DEV_FLAG_COUNT' not described in enum 'struct_device_flags' Add the description of DEV_FLAG_COUNT. Fixes: a2225b6e834a ("driver core: Don't let a device probe until it's ready") Reported-by: Randy Dunlap <rdunlap@infradead.org> Closes: https://lore.kernel.org/f318cd43-81fd-48b9-abf7-92af85f12f91@infradead.org Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Link: https://patch.msgid.link/20260413195910.1.I23aca74fe2d3636a47df196a80920fecb2643220@changeid Signed-off-by: Danilo Krummrich <dakr@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 5b484311507b5d403c1f7a45f6aa3778549e268b upstream.

Even though nobody should use this value (except when declaring the
"flags" bitmap), kernel-doc still gets upset that it's not documented.
It reports:

  WARNING: ../include/linux/device.h:519
  Enum value 'DEV_FLAG_COUNT' not described in enum 'struct_device_flags'

Add the description of DEV_FLAG_COUNT.

Fixes: a2225b6e834a ("driver core: Don't let a device probe until it's ready")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Closes: https://lore.kernel.org/f318cd43-81fd-48b9-abf7-92af85f12f91@infradead.org
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://patch.msgid.link/20260413195910.1.I23aca74fe2d3636a47df196a80920fecb2643220@changeid
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver core: Don't let a device probe until it's ready 2026-05-17T15:13:26+00:00 Douglas Anderson dianders@chromium.org 2026-04-27T16:52:41+00:00 29166a0e732fdd6b2bed72420f26bc2bea77f86f [ Upstream commit a2225b6e834a838ae3c93709760edc0a169eb2f2 ] The moment we link a "struct device" into the list of devices for the bus, it's possible probe can happen. This is because another thread can load the driver at any time and that can cause the device to probe. This has been seen in practice with a stack crawl that looks like this [1]: really_probe() __driver_probe_device() driver_probe_device() __driver_attach() bus_for_each_dev() driver_attach() bus_add_driver() driver_register() __platform_driver_register() init_module() [some module] do_one_initcall() do_init_module() load_module() __arm64_sys_finit_module() invoke_syscall() As a result of the above, it was seen that device_links_driver_bound() could be called for the device before "dev->fwnode->dev" was assigned. This prevented __fw_devlink_pickup_dangling_consumers() from being called which meant that other devices waiting on our driver's sub-nodes were stuck deferring forever. It's believed that this problem is showing up suddenly for two reasons: 1. Android has recently (last ~1 year) implemented an optimization to the order it loads modules [2]. When devices opt-in to this faster loading, modules are loaded one-after-the-other very quickly. This is unlike how other distributions do it. The reproduction of this problem has only been seen on devices that opt-in to Android's "parallel module loading". 2. Android devices typically opt-in to fw_devlink, and the most noticeable issue is the NULL "dev->fwnode->dev" in device_links_driver_bound(). fw_devlink is somewhat new code and also not in use by all Linux devices. Even though the specific symptom where "dev->fwnode->dev" wasn't assigned could be fixed by moving that assignment higher in device_add(), other parts of device_add() (like the call to device_pm_add()) are also important to run before probe. Only moving the "dev->fwnode->dev" assignment would likely fix the current symptoms but lead to difficult-to-debug problems in the future. Fix the problem by preventing probe until device_add() has run far enough that the device is ready to probe. If somehow we end up trying to probe before we're allowed, __driver_probe_device() will return -EPROBE_DEFER which will make certain the device is noticed. In the race condition that was seen with Android's faster module loading, we will temporarily add the device to the deferred list and then take it off immediately when device_add() probes the device. Instead of adding another flag to the bitfields already in "struct device", instead add a new "flags" field and use that. This allows us to freely change the bit from different thread without worrying about corrupting nearby bits (and means threads changing other bit won't corrupt us). [1] Captured on a machine running a downstream 6.6 kernel [2] https://cs.android.com/android/platform/superproject/main/+/main:system/core/libmodprobe/libmodprobe.cpp?q=LoadModulesParallel Cc: stable@vger.kernel.org Fixes: 2023c610dc54 ("Driver core: add new device to bus's list before probing") Reviewed-by: Alan Stern <stern@rowland.harvard.edu> Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org> Reviewed-by: Danilo Krummrich <dakr@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Link: https://patch.msgid.link/20260406162231.v5.1.Id750b0fbcc94f23ed04b7aecabcead688d0d8c17@changeid Signed-off-by: Danilo Krummrich <dakr@kernel.org> Signed-off-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit a2225b6e834a838ae3c93709760edc0a169eb2f2 ]

The moment we link a "struct device" into the list of devices for the
bus, it's possible probe can happen. This is because another thread
can load the driver at any time and that can cause the device to
probe. This has been seen in practice with a stack crawl that looks
like this [1]:

  really_probe()
  __driver_probe_device()
  driver_probe_device()
  __driver_attach()
  bus_for_each_dev()
  driver_attach()
  bus_add_driver()
  driver_register()
  __platform_driver_register()
  init_module() [some module]
  do_one_initcall()
  do_init_module()
  load_module()
  __arm64_sys_finit_module()
  invoke_syscall()

As a result of the above, it was seen that device_links_driver_bound()
could be called for the device before "dev->fwnode->dev" was
assigned. This prevented __fw_devlink_pickup_dangling_consumers() from
being called which meant that other devices waiting on our driver's
sub-nodes were stuck deferring forever.

It's believed that this problem is showing up suddenly for two
reasons:
1. Android has recently (last ~1 year) implemented an optimization to
   the order it loads modules [2]. When devices opt-in to this faster
   loading, modules are loaded one-after-the-other very quickly. This
   is unlike how other distributions do it. The reproduction of this
   problem has only been seen on devices that opt-in to Android's
   "parallel module loading".
2. Android devices typically opt-in to fw_devlink, and the most
   noticeable issue is the NULL "dev->fwnode->dev" in
   device_links_driver_bound(). fw_devlink is somewhat new code and
   also not in use by all Linux devices.

Even though the specific symptom where "dev->fwnode->dev" wasn't
assigned could be fixed by moving that assignment higher in
device_add(), other parts of device_add() (like the call to
device_pm_add()) are also important to run before probe. Only moving
the "dev->fwnode->dev" assignment would likely fix the current
symptoms but lead to difficult-to-debug problems in the future.

Fix the problem by preventing probe until device_add() has run far
enough that the device is ready to probe. If somehow we end up trying
to probe before we're allowed, __driver_probe_device() will return
-EPROBE_DEFER which will make certain the device is noticed.

In the race condition that was seen with Android's faster module
loading, we will temporarily add the device to the deferred list and
then take it off immediately when device_add() probes the device.

Instead of adding another flag to the bitfields already in "struct
device", instead add a new "flags" field and use that. This allows us
to freely change the bit from different thread without worrying about
corrupting nearby bits (and means threads changing other bit won't
corrupt us).

[1] Captured on a machine running a downstream 6.6 kernel
[2] https://cs.android.com/android/platform/superproject/main/+/main:system/core/libmodprobe/libmodprobe.cpp?q=LoadModulesParallel

Cc: stable@vger.kernel.org
Fixes: 2023c610dc54 ("Driver core: add new device to bus's list before probing")
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patch.msgid.link/20260406162231.v5.1.Id750b0fbcc94f23ed04b7aecabcead688d0d8c17@changeid
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
driver core/PM: Set power.no_callbacks along with power.no_pm 2025-10-12T10:56:22+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2025-08-28T10:59:24+00:00 e242e52fdfe4c4f4ad35b6264ff60cb12dfba131 commit c2ce2453413d429e302659abc5ace634e873f6f5 upstream. Devices with power.no_pm set are not expected to need any power management at all, so modify device_set_pm_not_required() to set power.no_callbacks for them too in case runtime PM will be enabled for any of them (which in principle may be done for convenience if such a device participates in a dependency chain). Since device_set_pm_not_required() must be called before device_add() or it would not have any effect, it can update power.no_callbacks without locking, unlike pm_runtime_no_callbacks() that can be called after registering the target device. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: stable <stable@kernel.org> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Link: https://lore.kernel.org/r/1950054.tdWV9SEqCh@rafael.j.wysocki Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c2ce2453413d429e302659abc5ace634e873f6f5 upstream.

Devices with power.no_pm set are not expected to need any power
management at all, so modify device_set_pm_not_required() to set
power.no_callbacks for them too in case runtime PM will be enabled
for any of them (which in principle may be done for convenience if
such a device participates in a dependency chain).

Since device_set_pm_not_required() must be called before device_add()
or it would not have any effect, it can update power.no_callbacks
without locking, unlike pm_runtime_no_callbacks() that can be called
after registering the target device.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: stable <stable@kernel.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/1950054.tdWV9SEqCh@rafael.j.wysocki
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cxl/port: Fix use-after-free, permit out-of-order decoder shutdown 2024-11-08T15:28:24+00:00 Dan Williams dan.j.williams@intel.com 2024-10-23T01:43:49+00:00 8e1b52c15c81106456437f8e49575040e489e355 commit 101c268bd2f37e965a5468353e62d154db38838e upstream. In support of investigating an initialization failure report [1], cxl_test was updated to register mock memory-devices after the mock root-port/bus device had been registered. That led to cxl_test crashing with a use-after-free bug with the following signature: cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem0:decoder7.0 @ 0 next: cxl_switch_uport.0 nr_eps: 1 nr_targets: 1 cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem4:decoder14.0 @ 1 next: cxl_switch_uport.0 nr_eps: 2 nr_targets: 1 cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[0] = cxl_switch_dport.0 for mem0:decoder7.0 @ 0 1) cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[1] = cxl_switch_dport.4 for mem4:decoder14.0 @ 1 [..] cxld_unregister: cxl decoder14.0: cxl_region_decode_reset: cxl_region region3: mock_decoder_reset: cxl_port port3: decoder3.0 reset 2) mock_decoder_reset: cxl_port port3: decoder3.0: out of order reset, expected decoder3.1 cxl_endpoint_decoder_release: cxl decoder14.0: [..] cxld_unregister: cxl decoder7.0: 3) cxl_region_decode_reset: cxl_region region3: Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6bc3: 0000 [#1] PREEMPT SMP PTI [..] RIP: 0010:to_cxl_port+0x8/0x60 [cxl_core] [..] Call Trace: <TASK> cxl_region_decode_reset+0x69/0x190 [cxl_core] cxl_region_detach+0xe8/0x210 [cxl_core] cxl_decoder_kill_region+0x27/0x40 [cxl_core] cxld_unregister+0x5d/0x60 [cxl_core] At 1) a region has been established with 2 endpoint decoders (7.0 and 14.0). Those endpoints share a common switch-decoder in the topology (3.0). At teardown, 2), decoder14.0 is the first to be removed and hits the "out of order reset case" in the switch decoder. The effect though is that region3 cleanup is aborted leaving it in-tact and referencing decoder14.0. At 3) the second attempt to teardown region3 trips over the stale decoder14.0 object which has long since been deleted. The fix here is to recognize that the CXL specification places no mandate on in-order shutdown of switch-decoders, the driver enforces in-order allocation, and hardware enforces in-order commit. So, rather than fail and leave objects dangling, always remove them. In support of making cxl_region_decode_reset() always succeed, cxl_region_invalidate_memregion() failures are turned into warnings. Crashing the kernel is ok there since system integrity is at risk if caches cannot be managed around physical address mutation events like CXL region destruction. A new device_for_each_child_reverse_from() is added to cleanup port->commit_end after all dependent decoders have been disabled. In other words if decoders are allocated 0->1->2 and disabled 1->2->0 then port->commit_end only decrements from 2 after 2 has been disabled, and it decrements all the way to zero since 1 was disabled previously. Link: http://lore.kernel.org/20241004212504.1246-1-gourry@gourry.net [1] Cc: stable@vger.kernel.org Fixes: 176baefb2eb5 ("cxl/hdm: Commit decoder state to hardware") Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Zijun Hu <quic_zijuhu@quicinc.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://patch.msgid.link/172964782781.81806.17902885593105284330.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 101c268bd2f37e965a5468353e62d154db38838e upstream.

In support of investigating an initialization failure report [1],
cxl_test was updated to register mock memory-devices after the mock
root-port/bus device had been registered. That led to cxl_test crashing
with a use-after-free bug with the following signature:

    cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem0:decoder7.0 @ 0 next: cxl_switch_uport.0 nr_eps: 1 nr_targets: 1
    cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem4:decoder14.0 @ 1 next: cxl_switch_uport.0 nr_eps: 2 nr_targets: 1
    cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[0] = cxl_switch_dport.0 for mem0:decoder7.0 @ 0
1)  cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[1] = cxl_switch_dport.4 for mem4:decoder14.0 @ 1
    [..]
    cxld_unregister: cxl decoder14.0:
    cxl_region_decode_reset: cxl_region region3:
    mock_decoder_reset: cxl_port port3: decoder3.0 reset
2)  mock_decoder_reset: cxl_port port3: decoder3.0: out of order reset, expected decoder3.1
    cxl_endpoint_decoder_release: cxl decoder14.0:
    [..]
    cxld_unregister: cxl decoder7.0:
3)  cxl_region_decode_reset: cxl_region region3:
    Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6bc3: 0000 [#1] PREEMPT SMP PTI
    [..]
    RIP: 0010:to_cxl_port+0x8/0x60 [cxl_core]
    [..]
    Call Trace:
     <TASK>
     cxl_region_decode_reset+0x69/0x190 [cxl_core]
     cxl_region_detach+0xe8/0x210 [cxl_core]
     cxl_decoder_kill_region+0x27/0x40 [cxl_core]
     cxld_unregister+0x5d/0x60 [cxl_core]

At 1) a region has been established with 2 endpoint decoders (7.0 and
14.0). Those endpoints share a common switch-decoder in the topology
(3.0). At teardown, 2), decoder14.0 is the first to be removed and hits
the "out of order reset case" in the switch decoder. The effect though
is that region3 cleanup is aborted leaving it in-tact and
referencing decoder14.0. At 3) the second attempt to teardown region3
trips over the stale decoder14.0 object which has long since been
deleted.

The fix here is to recognize that the CXL specification places no
mandate on in-order shutdown of switch-decoders, the driver enforces
in-order allocation, and hardware enforces in-order commit. So, rather
than fail and leave objects dangling, always remove them.

In support of making cxl_region_decode_reset() always succeed,
cxl_region_invalidate_memregion() failures are turned into warnings.
Crashing the kernel is ok there since system integrity is at risk if
caches cannot be managed around physical address mutation events like
CXL region destruction.

A new device_for_each_child_reverse_from() is added to cleanup
port->commit_end after all dependent decoders have been disabled. In
other words if decoders are allocated 0->1->2 and disabled 1->2->0 then
port->commit_end only decrements from 2 after 2 has been disabled, and
it decrements all the way to zero since 1 was disabled previously.

Link: http://lore.kernel.org/20241004212504.1246-1-gourry@gourry.net [1]
Cc: stable@vger.kernel.org
Fixes: 176baefb2eb5 ("cxl/hdm: Commit decoder state to hardware")
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Zijun Hu <quic_zijuhu@quicinc.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://patch.msgid.link/172964782781.81806.17902885593105284330.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver core: Introduce device_link_wait_removal() 2024-04-10T14:36:03+00:00 Herve Codina herve.codina@bootlin.com 2024-03-25T15:21:25+00:00 dfa65572768868d0a0414ac77cfcb949da8e4a9e commit 0462c56c290a99a7f03e817ae5b843116dfb575c upstream. The commit 80dd33cf72d1 ("drivers: base: Fix device link removal") introduces a workqueue to release the consumer and supplier devices used in the devlink. In the job queued, devices are release and in turn, when all the references to these devices are dropped, the release function of the device itself is called. Nothing is present to provide some synchronisation with this workqueue in order to ensure that all ongoing releasing operations are done and so, some other operations can be started safely. For instance, in the following sequence: 1) of_platform_depopulate() 2) of_overlay_remove() During the step 1, devices are released and related devlinks are removed (jobs pushed in the workqueue). During the step 2, OF nodes are destroyed but, without any synchronisation with devlink removal jobs, of_overlay_remove() can raise warnings related to missing of_node_put(): ERROR: memory leak, expected refcount 1 instead of 2 Indeed, the missing of_node_put() call is going to be done, too late, from the workqueue job execution. Introduce device_link_wait_removal() to offer a way to synchronize operations waiting for the end of devlink removals (i.e. end of workqueue jobs). Also, as a flushing operation is done on the workqueue, the workqueue used is moved from a system-wide workqueue to a local one. Cc: stable@vger.kernel.org Signed-off-by: Herve Codina <herve.codina@bootlin.com> Tested-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Reviewed-by: Nuno Sa <nuno.sa@analog.com> Reviewed-by: Saravana Kannan <saravanak@google.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20240325152140.198219-2-herve.codina@bootlin.com Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0462c56c290a99a7f03e817ae5b843116dfb575c upstream.

The commit 80dd33cf72d1 ("drivers: base: Fix device link removal")
introduces a workqueue to release the consumer and supplier devices used
in the devlink.
In the job queued, devices are release and in turn, when all the
references to these devices are dropped, the release function of the
device itself is called.

Nothing is present to provide some synchronisation with this workqueue
in order to ensure that all ongoing releasing operations are done and
so, some other operations can be started safely.

For instance, in the following sequence:
  1) of_platform_depopulate()
  2) of_overlay_remove()

During the step 1, devices are released and related devlinks are removed
(jobs pushed in the workqueue).
During the step 2, OF nodes are destroyed but, without any
synchronisation with devlink removal jobs, of_overlay_remove() can raise
warnings related to missing of_node_put():
  ERROR: memory leak, expected refcount 1 instead of 2

Indeed, the missing of_node_put() call is going to be done, too late,
from the workqueue job execution.

Introduce device_link_wait_removal() to offer a way to synchronize
operations waiting for the end of devlink removals (i.e. end of
workqueue jobs).
Also, as a flushing operation is done on the workqueue, the workqueue
used is moved from a system-wide workqueue to a local one.

Cc: stable@vger.kernel.org
Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Tested-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Reviewed-by: Saravana Kannan <saravanak@google.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20240325152140.198219-2-herve.codina@bootlin.com
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
driver core: Add a guard() definition for the device_lock() 2024-01-20T10:51:44+00:00 Dan Williams dan.j.williams@intel.com 2023-12-13T23:02:35+00:00 60e916d4b838ff7975012517be307461ec7b48fa [ Upstream commit 134c6eaa6087d78c0e289931ca15ae7a5007670d ] At present there are ~200 usages of device_lock() in the kernel. Some of those usages lead to "goto unlock;" patterns which have proven to be error prone. Define a "device" guard() definition to allow for those to be cleaned up and prevent new ones from appearing. Link: http://lore.kernel.org/r/657897453dda8_269bd29492@dwillia2-mobl3.amr.corp.intel.com.notmuch Link: http://lore.kernel.org/r/6577b0c2a02df_a04c5294bb@dwillia2-xfh.jf.intel.com.notmuch Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/170250854466.1522182.17555361077409628655.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 134c6eaa6087d78c0e289931ca15ae7a5007670d ]

At present there are ~200 usages of device_lock() in the kernel. Some of
those usages lead to "goto unlock;" patterns which have proven to be
error prone. Define a "device" guard() definition to allow for those to
be cleaned up and prevent new ones from appearing.

Link: http://lore.kernel.org/r/657897453dda8_269bd29492@dwillia2-mobl3.amr.corp.intel.com.notmuch
Link: http://lore.kernel.org/r/6577b0c2a02df_a04c5294bb@dwillia2-xfh.jf.intel.com.notmuch
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Link: https://lore.kernel.org/r/170250854466.1522182.17555361077409628655.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Merge tag 'driver-core-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core 2023-09-01T16:43:18+00:00 Linus Torvalds torvalds@linux-foundation.org 2023-09-01T16:43:18+00:00 28a4f91f5f251689c69155bc6a0b1afc9916c874 Pull driver core updates from Greg KH: "Here is a small set of driver core updates and additions for 6.6-rc1. Included in here are: - stable kernel documentation updates - class structure const work from Ivan on various subsystems - kernfs tweaks - driver core tests! - kobject sanity cleanups - kobject structure reordering to save space - driver core error code handling fixups - other minor driver core cleanups All of these have been in linux-next for a while with no reported problems" * tag 'driver-core-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (32 commits) driver core: Call in reversed order in device_platform_notify_remove() driver core: Return proper error code when dev_set_name() fails kobject: Remove redundant checks for whether ktype is NULL kobject: Add sanity check for kset->kobj.ktype in kset_register() drivers: base: test: Add missing MODULE_* macros to root device tests drivers: base: test: Add missing MODULE_* macros for platform devices tests drivers: base: Free devm resources when unregistering a device drivers: base: Add basic devm tests for platform devices drivers: base: Add basic devm tests for root devices kernfs: fix missing kernfs_iattr_rwsem locking docs: stable-kernel-rules: mention that regressions must be prevented docs: stable-kernel-rules: fine-tune various details docs: stable-kernel-rules: make the examples for option 1 a proper list docs: stable-kernel-rules: move text around to improve flow docs: stable-kernel-rules: improve structure by changing headlines base/node: Remove duplicated include kernfs: attach uuid for every kernfs and report it in fsid kernfs: add stub helper for kernfs_generic_poll() x86/resctrl: make pseudo_lock_class a static const structure x86/MSR: make msr_class a static const structure ... 
Pull driver core updates from Greg KH:
 "Here is a small set of driver core updates and additions for 6.6-rc1.

  Included in here are:

   - stable kernel documentation updates

   - class structure const work from Ivan on various subsystems

   - kernfs tweaks

   - driver core tests!

   - kobject sanity cleanups

   - kobject structure reordering to save space

   - driver core error code handling fixups

   - other minor driver core cleanups

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'driver-core-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (32 commits)
  driver core: Call in reversed order in device_platform_notify_remove()
  driver core: Return proper error code when dev_set_name() fails
  kobject: Remove redundant checks for whether ktype is NULL
  kobject: Add sanity check for kset->kobj.ktype in kset_register()
  drivers: base: test: Add missing MODULE_* macros to root device tests
  drivers: base: test: Add missing MODULE_* macros for platform devices tests
  drivers: base: Free devm resources when unregistering a device
  drivers: base: Add basic devm tests for platform devices
  drivers: base: Add basic devm tests for root devices
  kernfs: fix missing kernfs_iattr_rwsem locking
  docs: stable-kernel-rules: mention that regressions must be prevented
  docs: stable-kernel-rules: fine-tune various details
  docs: stable-kernel-rules: make the examples for option 1 a proper list
  docs: stable-kernel-rules: move text around to improve flow
  docs: stable-kernel-rules: improve structure by changing headlines
  base/node: Remove duplicated include
  kernfs: attach uuid for every kernfs and report it in fsid
  kernfs: add stub helper for kernfs_generic_poll()
  x86/resctrl: make pseudo_lock_class a static const structure
  x86/MSR: make msr_class a static const structure
  ...
Merge tag 'sound-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound 2023-08-30T20:45:05+00:00 Linus Torvalds torvalds@linux-foundation.org 2023-08-30T20:45:05+00:00 4fb0dacb78c6a041bbd38ddd998df806af5c2c69 Pull sound updates from Takashi Iwai: "We've received a fairly wide range of changes at this time, including for ALSA and ASoC core, but all of them are rather small changes. Here are some highlights: ALSA / ASoC Core: - Fixes of inconsistent locking around control API helpers - A few new control API functions and cleanups - Workarounds for potential UAFs by delayed kobj releases - Unified PCM copy ops with iov_iter - Continued efforts for ASoC API cleanups ASoC: - An adaptor to allow use of IIO DACs and ADCs in ASoC which pulls in some IIO changes - Create a library function for intlog10() and use it in the NAU8825 driver - Convert drivers to use the more modern maple tree register cache - Lots of work on the SOF framework, AMD and Intel drivers, including a lot of cleanup and new device support - Standardization of the presentation of jacks from drivers - Provision of some generic sound card DT properties - Support for AMD Van Gogh, AMD machines with MAX98388 and NAU8821, AWInic AW88261, Cirrus Logic CS35L36 and CS42L43, various Intel platforms including AVS machines with ES8336 and RT5663, Mediatek MT7986, NXP i.MX93, RealTek RT1017 and StarFive JH7110 Others: - New test coverage including ASoC and topology tests in KUnit; this also involves enabling UML builds of ALSA since that's the default KUnit test environment which pulls in the addition of some stubs to the driver - More enhancement of pcmtest driver - A few fixes / enhancements of MIDI 2.0 UMP core - Using PCI definitions in allover HD-audio code - Support for Cirrus CS35L56 and TI TAS2781 HD-audio sub-codecs - CS35L41 HD-audio sub-codec improvements - Continued emu10k1 improvements" * tag 'sound-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (693 commits) ALSA: pcm: Fix missing fixup call in compat hw_refine ioctl ASoC: dwc: i2s: Fix unused functions ALSA: usb-audio: Don't try to submit URBs after disconnection ALSA: emu10k1: add separate documentation for E-MU cards ALSA: emu10k1: more documentation updates ALSA: emu10k1: de-duplicate audigy-mixer.rst vs. sb-live-mixer.rst ALSA: ump: Fix -Wformat-truncation warnings ALSA: hda: Add missing dependency on CONFIG_EFI for Cirrus/TI sub-codecs ALSA: doc: Fix missing backquote in midi-2.0.rst ALSA: hda/realtek: Add quirk for mute LEDs on HP ENVY x360 15-eu0xxx ALSA: hda/tas2781: Switch back to use struct i2c_driver's .probe() ASoC: soc-core.c: Do not error if a DAI link component is not found ASoC: codecs: Fix error code in aw88261_i2c_probe() ASoC: audio-graph-card.c: move audio_graph_parse_of() ASoC: cs42l43: Use new-style PM runtime macros ALSA: documentation: Add description for USB MIDI 2.0 gadget driver ALSA: ump: Don't create unused substreams for static blocks ALSA: ump: Fill group names for legacy rawmidi substreams ALSA: usb-audio: Attach legacy rawmidi after probing all UMP EPs ALSA: ac97: Fix possible error value of *rac97 ... 
Pull sound updates from Takashi Iwai:
 "We've received a fairly wide range of changes at this time, including
  for ALSA and ASoC core, but all of them are rather small changes.

  Here are some highlights:

  ALSA / ASoC Core:
   - Fixes of inconsistent locking around control API helpers
   - A few new control API functions and cleanups
   - Workarounds for potential UAFs by delayed kobj releases
   - Unified PCM copy ops with iov_iter
   - Continued efforts for ASoC API cleanups

  ASoC:
   - An adaptor to allow use of IIO DACs and ADCs in ASoC which pulls in
     some IIO changes
   - Create a library function for intlog10() and use it in the NAU8825
     driver
   - Convert drivers to use the more modern maple tree register cache
   - Lots of work on the SOF framework, AMD and Intel drivers, including
     a lot of cleanup and new device support
   - Standardization of the presentation of jacks from drivers
   - Provision of some generic sound card DT properties
   - Support for AMD Van Gogh, AMD machines with MAX98388 and NAU8821,
     AWInic AW88261, Cirrus Logic CS35L36 and CS42L43, various Intel
     platforms including AVS machines with ES8336 and RT5663, Mediatek
     MT7986, NXP i.MX93, RealTek RT1017 and StarFive JH7110

  Others:
   - New test coverage including ASoC and topology tests in KUnit; this
     also involves enabling UML builds of ALSA since that's the default
     KUnit test environment which pulls in the addition of some stubs to
     the driver
   - More enhancement of pcmtest driver
   - A few fixes / enhancements of MIDI 2.0 UMP core
   - Using PCI definitions in allover HD-audio code
   - Support for Cirrus CS35L56 and TI TAS2781 HD-audio sub-codecs
   - CS35L41 HD-audio sub-codec improvements
   - Continued emu10k1 improvements"

* tag 'sound-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (693 commits)
  ALSA: pcm: Fix missing fixup call in compat hw_refine ioctl
  ASoC: dwc: i2s: Fix unused functions
  ALSA: usb-audio: Don't try to submit URBs after disconnection
  ALSA: emu10k1: add separate documentation for E-MU cards
  ALSA: emu10k1: more documentation updates
  ALSA: emu10k1: de-duplicate audigy-mixer.rst vs. sb-live-mixer.rst
  ALSA: ump: Fix -Wformat-truncation warnings
  ALSA: hda: Add missing dependency on CONFIG_EFI for Cirrus/TI sub-codecs
  ALSA: doc: Fix missing backquote in midi-2.0.rst
  ALSA: hda/realtek: Add quirk for mute LEDs on HP ENVY x360 15-eu0xxx
  ALSA: hda/tas2781: Switch back to use struct i2c_driver's .probe()
  ASoC: soc-core.c: Do not error if a DAI link component is not found
  ASoC: codecs: Fix error code in aw88261_i2c_probe()
  ASoC: audio-graph-card.c: move audio_graph_parse_of()
  ASoC: cs42l43: Use new-style PM runtime macros
  ALSA: documentation: Add description for USB MIDI 2.0 gadget driver
  ALSA: ump: Don't create unused substreams for static blocks
  ALSA: ump: Fill group names for legacy rawmidi substreams
  ALSA: usb-audio: Attach legacy rawmidi after probing all UMP EPs
  ALSA: ac97: Fix possible error value of *rac97
  ...
driver core: Move dev_err_probe() to where it belogs 2023-08-05T06:31:41+00:00 Andy Shevchenko andriy.shevchenko@linux.intel.com 2023-07-21T13:13:09+00:00 9e0cace7a6254070159ebd86497eadc29ea307ca dev_err_probe() belongs to the printing API, hence move the definition from device.h to dev_printk.h. There is no change to the callers at all, since: 1) implementation is located in the same core.c; 2) dev_printk.h is guaranteed to be included by device.h. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Link: https://lore.kernel.org/r/20230721131309.16821-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
dev_err_probe() belongs to the printing API, hence
move the definition from device.h to dev_printk.h.

There is no change to the callers at all, since:
1) implementation is located in the same core.c;
2) dev_printk.h is guaranteed to be included by device.h.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20230721131309.16821-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
swiotlb: search the software IO TLB only if the device makes use of it 2023-08-01T16:02:32+00:00 Petr Tesarik petr.tesarik.ext@huawei.com 2023-08-01T06:24:04+00:00 1395706a14904f2593debecf20f827e72d7392a7 Skip searching the software IO TLB if a device has never used it, making sure these devices are not affected by the introduction of multiple IO TLB memory pools. Additional memory barrier is required to ensure that the new value of the flag is visible to other CPUs after mapping a new bounce buffer. For efficiency, the flag check should be inlined, and then the memory barrier must be moved to is_swiotlb_buffer(). However, it can replace the existing barrier in swiotlb_find_pool(), because all callers use is_swiotlb_buffer() first to verify that the buffer address belongs to the software IO TLB. Signed-off-by: Petr Tesarik <petr.tesarik.ext@huawei.com> Signed-off-by: Christoph Hellwig <hch@lst.de> 
Skip searching the software IO TLB if a device has never used it, making
sure these devices are not affected by the introduction of multiple IO TLB
memory pools.

Additional memory barrier is required to ensure that the new value of the
flag is visible to other CPUs after mapping a new bounce buffer. For
efficiency, the flag check should be inlined, and then the memory barrier
must be moved to is_swiotlb_buffer(). However, it can replace the existing
barrier in swiotlb_find_pool(), because all callers use is_swiotlb_buffer()
first to verify that the buffer address belongs to the software IO TLB.

Signed-off-by: Petr Tesarik <petr.tesarik.ext@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>