Because pm_runtime_get_suppliers() bumps up the rpm_active counter
of each device link to a supplier of the given device in addition
to bumping up the supplier's PM-runtime usage counter, a runtime
suspend of the consumer device may case the latter to go down to 0
when pm_runtime_put_suppliers() is running on a remote CPU. If that
happens after pm_runtime_put_suppliers() has released power.lock for
the consumer device, and a runtime resume of that device takes place
immediately after it, before pm_runtime_put() is called for the
supplier, that pm_runtime_put() call may cause the supplier to be
suspended even though the consumer is active.
To prevent that from happening, modify pm_runtime_get_suppliers() to
call pm_runtime_get_sync() for the given device's suppliers without
touching the rpm_active counters of the involved device links
Accordingly, modify pm_runtime_put_suppliers() to call pm_runtime_put()
for the given device's suppliers without looking at the rpm_active
counters of the device links at hand. [This is analogous to what
happened before commit 4c06c4e6cf ("driver core: Fix possible
supplier PM-usage counter imbalance").]
Since pm_runtime_get_suppliers() sets supplier_preactivated for each
device link where the supplier's PM-runtime usage counter has been
incremented and pm_runtime_put_suppliers() calls pm_runtime_put() for
the suppliers whose device links have supplier_preactivated set, the
PM-runtime usage counter is balanced for each supplier and this is
independent of the runtime suspend and resume of the consumer device.
However, in case a device link with DL_FLAG_PM_RUNTIME set is dropped
during the consumer device probe, so pm_runtime_get_suppliers() bumps
up the supplier's PM-runtime usage counter, but it cannot be dropped by
pm_runtime_put_suppliers(), make device_link_release_fn() take care of
that.
Fixes: 4c06c4e6cf ("driver core: Fix possible supplier PM-usage counter imbalance")
Reported-by: Peter Wang <peter.wang@mediatek.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Peter Wang <peter.wang@mediatek.com>
Cc: 5.1+ <stable@vger.kernel.org> # 5.1+
Instead of passing an extra bool argument to pm_runtime_release_supplier(),
make its callers take care of triggering a runtime-suspend of the
supplier device as needed.
No expected functional impact.
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: 5.1+ <stable@vger.kernel.org> # 5.1+
Pull driver core updates from Greg KH:
"Here is the set of driver core changes for 5.19-rc1.
Lots of tiny driver core changes and cleanups happened this cycle, but
the two major things are:
- firmware_loader reorganization and additions including the ability
to have XZ compressed firmware images and the ability for userspace
to initiate the firmware load when it needs to, instead of being
always initiated by the kernel. FPGA devices specifically want this
ability to have their firmware changed over the lifetime of the
system boot, and this allows them to work without having to come up
with yet-another-custom-uapi interface for loading firmware for
them.
- physical location support added to sysfs so that devices that know
this information, can tell userspace where they are located in a
common way. Some ACPI devices already support this today, and more
bus types should support this in the future.
Smaller changes include:
- driver_override api cleanups and fixes
- error path cleanups and fixes
- get_abi script fixes
- deferred probe timeout changes.
It's that last change that I'm the most worried about. It has been
reported to cause boot problems for a number of systems, and I have a
tested patch series that resolves this issue. But I didn't get it
merged into my tree before 5.18-final came out, so it has not gotten
any linux-next testing.
I'll send the fixup patches (there are 2) as a follow-on series to this
pull request.
All have been tested in linux-next for weeks, with no reported issues
other than the above-mentioned boot time-outs"
* tag 'driver-core-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits)
driver core: fix deadlock in __device_attach
kernfs: Separate kernfs_pr_cont_buf and rename_lock.
topology: Remove unused cpu_cluster_mask()
driver core: Extend deferred probe timeout on driver registration
MAINTAINERS: add Russ Weight as a firmware loader maintainer
driver: base: fix UAF when driver_attach failed
test_firmware: fix end of loop test in upload_read_show()
driver core: location: Add "back" as a possible output for panel
driver core: location: Free struct acpi_pld_info *pld
driver core: Add "*" wildcard support to driver_async_probe cmdline param
driver core: location: Check for allocations failure
arch_topology: Trace the update thermal pressure
kernfs: Rename kernfs_put_open_node to kernfs_unlink_open_file.
export: fix string handling of namespace in EXPORT_SYMBOL_NS
rpmsg: use local 'dev' variable
rpmsg: Fix calling device_lock() on non-initialized device
firmware_loader: describe 'module' parameter of firmware_upload_register()
firmware_loader: Move definitions from sysfs_upload.h to sysfs.h
firmware_loader: Fix configs for sysfs split
selftests: firmware: Add firmware upload selftests
...
When ACPI table includes _PLD fields for a device, create a new
directory (physical_location) in sysfs to share _PLD fields.
Currently without PLD information, when there are multiple of same
devices, it is hard to distinguish which device corresponds to which
physical device at which location. For example, when there are two Type
C connectors, it is hard to find out which connector corresponds to the
Type C port on the left panel versus the Type C port on the right panel.
With PLD information provided, we can determine which specific device at
which location is doing what.
_PLD output includes much more fields, but only generic fields are added
and exposed to sysfs, so that non-ACPI devices can also support it in
the future. The minimal generic fields needed for locating a device are
the following.
- panel
- vertical_position
- horizontal_position
- dock
- lid
Signed-off-by: Won Chung <wonchung@google.com>
Link: https://lore.kernel.org/r/20220314195458.271430-1-wonchung@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull MSI irq updates from Thomas Gleixner:
"Rework of the MSI interrupt infrastructure.
This is a treewide cleanup and consolidation of MSI interrupt handling
in preparation for further changes in this area which are necessary
to:
- address existing shortcomings in the VFIO area
- support the upcoming Interrupt Message Store functionality which
decouples the message store from the PCI config/MMIO space"
* tag 'irq-msi-2022-01-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (94 commits)
genirq/msi: Populate sysfs entry only once
PCI/MSI: Unbreak pci_irq_get_affinity()
genirq/msi: Convert storage to xarray
genirq/msi: Simplify sysfs handling
genirq/msi: Add abuse prevention comment to msi header
genirq/msi: Mop up old interfaces
genirq/msi: Convert to new functions
genirq/msi: Make interrupt allocation less convoluted
platform-msi: Simplify platform device MSI code
platform-msi: Let core code handle MSI descriptors
bus: fsl-mc-msi: Simplify MSI descriptor handling
soc: ti: ti_sci_inta_msi: Remove ti_sci_inta_msi_domain_free_irqs()
soc: ti: ti_sci_inta_msi: Rework MSI descriptor allocation
NTB/msi: Convert to msi_on_each_desc()
PCI: hv: Rework MSI handling
powerpc/mpic_u3msi: Use msi_for_each-desc()
powerpc/fsl_msi: Use msi_for_each_desc()
powerpc/pasemi/msi: Convert to msi_on_each_dec()
powerpc/cell/axon_msi: Convert to msi_on_each_desc()
powerpc/4xx/hsta: Rework MSI handling
...
Pull driver core updates from Greg KH:
"Here is the set of changes for the driver core for 5.17-rc1.
Lots of little things here, including:
- kobj_type cleanups
- auxiliary_bus documentation updates
- auxiliary_device conversions for some drivers (relevant subsystems
all have provided acks for these)
- kernfs lock contention reduction for some workloads
- other tiny cleanups and changes.
All of these have been in linux-next for a while with no reported
issues"
* tag 'driver-core-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (43 commits)
kobject documentation: remove default_attrs information
drivers/firmware: Add missing platform_device_put() in sysfb_create_simplefb
debugfs: lockdown: Allow reading debugfs files that are not world readable
driver core: Make bus notifiers in right order in really_probe()
driver core: Move driver_sysfs_remove() after driver_sysfs_add()
firmware: edd: remove empty default_attrs array
firmware: dmi-sysfs: use default_groups in kobj_type
qemu_fw_cfg: use default_groups in kobj_type
firmware: memmap: use default_groups in kobj_type
sh: sq: use default_groups in kobj_type
headers/uninline: Uninline single-use function: kobject_has_children()
devtmpfs: mount with noexec and nosuid
driver core: Simplify async probe test code by using ktime_ms_delta()
nilfs2: use default_groups in kobj_type
kobject: remove kset from struct kset_uevent_ops callbacks
driver core: make kobj_type constant.
driver core: platform: document registration-failure requirement
vdpa/mlx5: Use auxiliary_device driver data helpers
net/mlx5e: Use auxiliary_device driver data helpers
soundwire: intel: Use auxiliary_device driver data helpers
...
This was the only usage of <linux/kref_api.h> in <linux/kobject_api.h>,
so we'll able to decouple the two after this change.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Because refcount_dec_not_one() returns true if the target refcount
becomes saturated, it is generally unsafe to use its return value as
a loop termination condition, but that is what happens when a device
link's supplier device is released during runtime PM suspend
operations and on device link removal.
To address this, introduce pm_runtime_release_supplier() to be used
in the above cases which will check the supplier device's runtime
PM usage counter in addition to the refcount_dec_not_one() return
value, so the loop can be terminated in case the rpm_active refcount
value becomes invalid, and update the code in question to use it as
appropriate.
This change is not expected to have any visible functional impact.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
All the drivers that relied on device_del() to call
device_remove_properties() have now been converted to either
use device_create_managed_software_node() instead of
device_add_properties(), or to register the software node
completely separately from the device.
This will make it finally possible to share and reuse the
software nodes that hold the additional device properties.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
SYNC_STATE_ONLY device links intentionally allow cycles because cyclic
sync_state() dependencies are valid and necessary.
However a SYNC_STATE_ONLY device link where the consumer and the supplier
are the same device is pointless because the device link would be deleted
as soon as the device probes (because it's also the consumer) and won't
affect when the sync_state() callback is called. It's a waste of CPU cycles
and memory to create this device link. So reject any attempts to create
such a device link.
Fixes: 05ef983e0d ("driver core: Add device link support for SYNC_STATE_ONLY flag")
Cc: stable <stable@vger.kernel.org>
Reported-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20210929190549.860541-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
I got memory leak as follows:
unreferenced object 0xffff88801f0b2200 (size 64):
comm "i2c-lis2hh12-21", pid 5455, jiffies 4294944606 (age 15.224s)
hex dump (first 32 bytes):
72 65 67 75 6c 61 74 6f 72 3a 72 65 67 75 6c 61 regulator:regula
74 6f 72 2e 30 2d 2d 69 32 63 3a 31 2d 30 30 31 tor.0--i2c:1-001
backtrace:
[<00000000bf5b0c3b>] __kmalloc_track_caller+0x19f/0x3a0
[<0000000050da42d9>] kvasprintf+0xb5/0x150
[<000000004bbbed13>] kvasprintf_const+0x60/0x190
[<00000000cdac7480>] kobject_set_name_vargs+0x56/0x150
[<00000000bf83f8e8>] dev_set_name+0xc0/0x100
[<00000000cc1cf7e3>] device_link_add+0x6b4/0x17c0
[<000000009db9faed>] _regulator_get+0x297/0x680
[<00000000845e7f2b>] _devm_regulator_get+0x5b/0xe0
[<000000003958ee25>] st_sensors_power_enable+0x71/0x1b0 [st_sensors]
[<000000005f450f52>] st_accel_i2c_probe+0xd9/0x150 [st_accel_i2c]
[<00000000b5f2ab33>] i2c_device_probe+0x4d8/0xbe0
[<0000000070fb977b>] really_probe+0x299/0xc30
[<0000000088e226ce>] __driver_probe_device+0x357/0x500
[<00000000c21dda32>] driver_probe_device+0x4e/0x140
[<000000004e650441>] __device_attach_driver+0x257/0x340
[<00000000cf1891b8>] bus_for_each_drv+0x166/0x1e0
When device_register() returns an error, the name allocated in dev_set_name()
will be leaked, the put_device() should be used instead of kfree() to give up
the device reference, then the name will be freed in kobject_cleanup() and the
references of consumer and supplier will be decreased in device_link_release_fn().
Fixes: 287905e68d ("driver core: Expose device link details in sysfs")
Reported-by: Hulk Robot <hulkci@huawei.com>
Reviewed-by: Saravana Kannan <saravanak@google.com>
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20210930085714.2057460-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
