The devlink device name is of the form "supplier:consumer". But ":" is
fairly common in device names and makes it visually hard to distinguish
supplier and consumer. So, replace it with "--" to make it easier.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200724180523.1393383-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Marek and Guenter reported that commit 287905e68d ("driver core:
Expose device link details in sysfs") caused sleeping/scheduling while
atomic warnings.
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:935
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 12, name: kworker/0:1
2 locks held by kworker/0:1/12:
#0: ee8074a8 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x174/0x7dc
#1: ee921f20 ((work_completion)(&sdp->work)){+.+.}-{0:0}, at: process_one_work+0x174/0x7dc
Preemption disabled at:
[<c01b10f0>] srcu_invoke_callbacks+0xc0/0x154
----- 8< ----- SNIP
[<c064590c>] (device_del) from [<c0645c9c>] (device_unregister+0x24/0x64)
[<c0645c9c>] (device_unregister) from [<c01b10fc>] (srcu_invoke_callbacks+0xcc/0x154)
[<c01b10fc>] (srcu_invoke_callbacks) from [<c01493c4>] (process_one_work+0x234/0x7dc)
[<c01493c4>] (process_one_work) from [<c01499b0>] (worker_thread+0x44/0x51c)
[<c01499b0>] (worker_thread) from [<c0150bf4>] (kthread+0x158/0x1a0)
[<c0150bf4>] (kthread) from [<c0100114>] (ret_from_fork+0x14/0x20)
Exception stack(0xee921fb0 to 0xee921ff8)
This was caused by the device link device being released in the context
of srcu_invoke_callbacks(). There is no need to wait till the RCU
callback to release the device link device. So release the device
earlier and move the call_srcu() into the device release code. That way,
the memory will get freed only after the device is released AND the RCU
callback is called.
Fixes: 287905e68d ("driver core: Expose device link details in sysfs")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20200716214523.2924704-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This would be useful to check if a device is not probing because it's
waiting for a supplier to be added and then linked to before it can
probe.
To reduce sysfs clutter, this file is added only if it can ever be 1.
So, if fw_devlink is disabled or set to permissive, this file is not
added. Also, this file is removed once the device probes as it's no
longer relevant.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200521191800.136035-4-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's helpful to be able to look at device link details from sysfs. So,
expose it in sysfs.
Say device-A is supplier of device-B. These are the additional files
this patch would create:
/sys/class/devlink/device-A:device-B/
auto_remove_on
consumer/ -> .../device-B/
runtime_pm
status
supplier/ -> .../device-A/
sync_state_only
/sys/devices/.../device-A/
consumer:device-B/ -> /sys/class/devlink/device-A:device-B/
/sys/devices/.../device-B/
supplier:device-A/ -> /sys/class/devlink/device-A:device-B/
That way:
To get a list of all the device link in the system:
ls /sys/class/devlink/
To get the consumer names and links of a device:
ls -d /sys/devices/.../device-X/consumer:*
To get the supplier names and links of a device:
ls -d /sys/devices/.../device-X/supplier:*
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200521191800.136035-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With the earlier patch in this series, all devices that deferred probe
due to fw_devlink_pause() will have their probes delayed till the
deferred probe thread is kicked off during late_initcall. This will also
affect all their consumers.
This delayed probing in unnecessary. So this patch just keeps track of
the devices that had their probe deferred due to fw_devlink_pause() and
attempts to probe them once during fw_devlink_resume().
Fixes: 716a7a2596 ("driver core: fw_devlink: Add support for batching fwnode parsing")
Signed-off-by: Saravana Kannan <saravanak@google.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200701194259.3337652-4-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The defer_sync field is used as a hook to add the device to the
deferred_sync list. Rename it so that it's more meaningful for the next
patch that'll also use this field as a hook to a deferred_fw_devlink
list.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200701194259.3337652-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current deferred probe implementation can mess up suspend/resume
ordering if deferred probe thread is kicked off in parallel with the
main initcall thread (kernel_init thread) [1].
For example:
Say device-B is a consumer of device-A.
Initcall thread Deferred probe thread
=============== =====================
1. device-A is added.
2. device-B is added.
3. dpm_list is now [device-A, device-B].
4. driver-A defers probe of device-A.
5. device-A is moved to
end of dpm_list
6. dpm_list is now
[device-B, device-A]
7. driver-B is registereed and probes device-B.
8. dpm_list stays as [device-B, device-A].
The reverse order of dpm_list is used for suspend. So in this case
device-A would incorrectly get suspended before device-B.
Commit 716a7a2596 ("driver core: fw_devlink: Add support for batching
fwnode parsing") kicked off the deferred probe thread early during boot
to run in parallel with the initcall thread and caused suspend/resume
regressions. This patch removes the parallel run of the deferred probe
thread to avoid the suspend/resume regressions.
[1] - https://lore.kernel.org/lkml/CAGETcx8W96KAw-d_siTX4qHB_-7ddk0miYRDQeHE6E0_8qx-6Q@mail.gmail.com/
Fixes: 716a7a2596 ("driver core: fw_devlink: Add support for batching fwnode parsing")
Signed-off-by: Saravana Kannan <saravanak@google.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200701194259.3337652-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here is the set of driver core patches for 5.8-rc1.
Not all that huge this release, just a number of small fixes and
updates:
- software node fixes
- kobject now sends KOBJ_REMOVE when it is removed from sysfs,
not when it is removed from memory (which could come much
later)
- device link additions and fixes based on testing on more
devices
- firmware core cleanups
- other minor changes, full details in the shortlog
All have been in linux-next for a while with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the set of driver core patches for 5.8-rc1.
Not all that huge this release, just a number of small fixes and
updates:
- software node fixes
- kobject now sends KOBJ_REMOVE when it is removed from sysfs, not
when it is removed from memory (which could come much later)
- device link additions and fixes based on testing on more devices
- firmware core cleanups
- other minor changes, full details in the shortlog
All have been in linux-next for a while with no reported issues"
* tag 'driver-core-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (23 commits)
driver core: Update device link status correctly for SYNC_STATE_ONLY links
firmware_loader: change enum fw_opt to u32
software node: implement software_node_unregister()
kobject: send KOBJ_REMOVE uevent when the object is removed from sysfs
driver core: Remove unnecessary is_fwnode_dev variable in device_add()
drivers property: When no children in primary, try secondary
driver core: platform: Fix spelling errors in platform.c
driver core: Remove check in driver_deferred_probe_force_trigger()
of: platform: Batch fwnode parsing when adding all top level devices
driver core: fw_devlink: Add support for batching fwnode parsing
driver core: Look for waiting consumers only for a fwnode's primary device
driver core: Move code to the right part of the file
Revert "Revert "driver core: Set fw_devlink to "permissive" behavior by default""
drivers: base: Fix NULL pointer exception in __platform_driver_probe() if a driver developer is foolish
firmware_loader: move fw_fallback_config to a private kernel symbol namespace
driver core: Add missing '\n' in log messages
driver/base/soc: Use kobj_to_dev() API
Add documentation on meaning of -EPROBE_DEFER
driver core: platform: remove redundant assignment to variable ret
debugfs: Use the correct style for SPDX License Identifier
...
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Merge tag 'for-5.8/block-2020-06-01' of git://git.kernel.dk/linux-block
Pull block updates from Jens Axboe:
"Core block changes that have been queued up for this release:
- Remove dead blk-throttle and blk-wbt code (Guoqing)
- Include pid in blktrace note traces (Jan)
- Don't spew I/O errors on wouldblock termination (me)
- Zone append addition (Johannes, Keith, Damien)
- IO accounting improvements (Konstantin, Christoph)
- blk-mq hardware map update improvements (Ming)
- Scheduler dispatch improvement (Salman)
- Inline block encryption support (Satya)
- Request map fixes and improvements (Weiping)
- blk-iocost tweaks (Tejun)
- Fix for timeout failing with error injection (Keith)
- Queue re-run fixes (Douglas)
- CPU hotplug improvements (Christoph)
- Queue entry/exit improvements (Christoph)
- Move DMA drain handling to the few drivers that use it (Christoph)
- Partition handling cleanups (Christoph)"
* tag 'for-5.8/block-2020-06-01' of git://git.kernel.dk/linux-block: (127 commits)
block: mark bio_wouldblock_error() bio with BIO_QUIET
blk-wbt: rename __wbt_update_limits to wbt_update_limits
blk-wbt: remove wbt_update_limits
blk-throttle: remove tg_drain_bios
blk-throttle: remove blk_throtl_drain
null_blk: force complete for timeout request
blk-mq: drain I/O when all CPUs in a hctx are offline
blk-mq: add blk_mq_all_tag_iter
blk-mq: open code __blk_mq_alloc_request in blk_mq_alloc_request_hctx
blk-mq: use BLK_MQ_NO_TAG in more places
blk-mq: rename BLK_MQ_TAG_FAIL to BLK_MQ_NO_TAG
blk-mq: move more request initialization to blk_mq_rq_ctx_init
blk-mq: simplify the blk_mq_get_request calling convention
blk-mq: remove the bio argument to ->prepare_request
nvme: force complete cancelled requests
blk-mq: blk-mq: provide forced completion method
block: fix a warning when blkdev.h is included for !CONFIG_BLOCK builds
block: blk-crypto-fallback: remove redundant initialization of variable err
block: reduce part_stat_lock() scope
block: use __this_cpu_add() instead of access by smp_processor_id()
...
* Add a support of the media keys on the ASUS laptop UX325JA/UX425JA
* ASUS WMI driver can now handle 2-in-1 models T100TA, T100CHI, T100HA, T200TA
* Big refactoring of Intel SCU driver with Elkhart Lake support has been added
* Slim Bootloarder firmware update signaling WMI driver has been added
* Thinkpad ACPI driver can handle dual fan configuration on new P and X models
* Touchscreen DMI driver has been extended to support
- MP-man MPWIN895CL tablet
- ONDA V891 v5 tablet
- techBite Arc 11.6
- Trekstor Twin 10.1
- Trekstor Yourbook C11B
- Vinga J116
* Virtual Button driver got a few fixes to detect mode of 2-in-1 tablet models
* Intel Speed Select tools update
* Plenty of small cleanups here and there
The following is an automated git shortlog grouped by driver:
acerhdf:
- replace space by * in modalias
New drivers:
- Add Elkhart Lake SCU/PMC support
- Add Slim Bootloader firmware update signaling driver
asus-laptop:
- Drop duplicate check for led_classdev_unregister()
asus-nb-wmi:
- Revert "Do not load on Asus T100TA and T200TA"
- Do not load on Asus T100TA and T200TA
asus-wmi:
- Ignore WMI events with code 0x79
- Add support for SW_TABLET_MODE
- Move asus_wmi_input_init and _exit lower in the file
- Drop duplicate check for led_classdev_unregister()
- Reserve more space for struct bias_args
- remove redundant initialization of variable status
dcdbas:
- Check SMBIOS for protected buffer address
dell-laptop:
- don't register micmute LED if there is no token
dell-wmi:
- Ignore keyboard attached / detached events
device property:
- export set_secondary_fwnode() to modules
eeepc-laptop:
- Drop duplicate check for led_classdev_unregister()
hp-wmi:
- Introduce HPWMI_POWER_FW_OR_HW as convenient shortcut
- Convert simple_strtoul() to kstrtou32()
- Refactor postcode_store() to follow standard patterns
intel_cht_int33fe:
- Fix spelling issues
- Switch to use acpi_dev_hid_uid_match()
- Convert to use set_secondary_fwnode()
- Convert software node array to group
intel-hid:
- Add a quirk to support HP Spectre X2 (2015)
intel_mid_powerbtn:
- Convert to use new SCU IPC API
intel_pmc_core:
- avoid unused-function warnings
- Change Jasper Lake S0ix debug reg map back to ICL
intel_pmc_ipc:
- Convert to MFD
- Move PCI IDs to intel_scu_pcidrv.c
- Drop intel_pmc_ipc_command()
- Start using SCU IPC
intel_scu_ipc:
- Add managed function to register SCU IPC
- Introduce new SCU IPC API
- Move legacy SCU IPC API to a separate header
- Log more information if SCU IPC command fails
- Split out SCU IPC functionality from the SCU driver
intel_scu_ipcutil:
- Convert to use new SCU IPC API
intel-speed-select:
- Fix speed-select-base-freq-properties output on CLX-N
intel_telemetry:
- Add telemetry_get_pltdata()
- Convert to use new SCU IPC API
intel-vbtn:
- Only blacklist SW_TABLET_MODE on the 9 / "Laptop" chasis-type
- Detect switch position before registering the input-device
- Move detect_tablet_mode() to higher in the file
- Fix probe failure on devices with only switches
- Also handle tablet-mode switch on "Detachable" and "Portable" chassis-types
- Do not advertise switches to userspace if they are not there
- Split keymap into buttons and switches parts
- Use acpi_evaluate_integer()
ISST:
- Increase timeout
lg-laptop:
- Drop duplicate check for led_classdev_unregister()
MAINTAINERS:
- Add me as maintainer of Intel SCU drivers
- Update entry for Intel Broxton PMC driver
Merges of immutable branches:
- Merge branch 'for-next'
- Merge branch 'ib-mfd-x86-usb-watchdog-v5.7'
- Merge branch 'ib-pdx86-properties'
mfd:
- intel_soc_pmic_mrfld: Convert to use new SCU IPC API
- intel_soc_pmic_bxtwc: Convert to use new SCU IPC API
- intel_soc_pmic: Add SCU IPC member to struct intel_soc_pmic
samsung-laptop:
- Drop duplicate check for led_classdev_unregister()
software node:
- Allow register and unregister software node groups
sony-laptop:
- Make resuming thermal profile safer
- SNC calls should handle BUFFER types
thinkpad_acpi:
- Replace custom approach by kstrtoint()
- Use strndup_user() in dispatch_proc_write()
- Replace next_cmd(&buf) with strsep(&buf, ",")
- Drop duplicate check for led_classdev_unregister()
- Remove always false 'value < 0' statement
- Add support for dual fan control
tools/power/x86/intel-speed-select:
- Fix invalid core mask
- Increase CPU count
- Fix json perf-profile output output
- Update version
- Enable clos for turbo-freq enable
- Fix CLX-N package information output
- Check support status before enable
- Change debug to error
toshiba_acpi:
- Drop duplicate check for led_classdev_unregister()
touchscreen_dmi:
- Update Trekstor Twin 10.1 entry
- Add info for the Trekstor Yourbook C11B
- Drop comma in terminator line
- add Vinga J116 touchscreen
- Add info for the ONDA V891 v5 tablet
- Add touchscreen info for techBite Arc 11.6.
- Add info for the MP-man MPWIN895CL tablet
usb:
- typec: mux: Convert the Intel PMC Mux driver to use new SCU IPC API
watchdog:
- iTCO: fix link error
- intel-mid_wdt: Convert to use new SCU IPC API
wmi:
- Describe function parameters
- Fix indentation in some cases
- Replace UUID redefinitions by their originals
x86/platform/intel-mid:
- Add empty stubs for intel_scu_devices_[create|destroy]()
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Merge tag 'platform-drivers-x86-v5.8-1' of git://git.infradead.org/linux-platform-drivers-x86
Pull x86 platform driver updates from Andy Shevchenko:
- Add a support of the media keys on the ASUS laptop UX325JA/UX425JA
- ASUS WMI driver can now handle 2-in-1 models T100TA, T100CHI, T100HA,
T200TA
- Big refactoring of Intel SCU driver with Elkhart Lake support has
been added
- Slim Bootloarder firmware update signaling WMI driver has been added
- Thinkpad ACPI driver can handle dual fan configuration on new P and X
models
- Touchscreen DMI driver has been extended to support
- MP-man MPWIN895CL tablet
- ONDA V891 v5 tablet
- techBite Arc 11.6
- Trekstor Twin 10.1
- Trekstor Yourbook C11B
- Vinga J116
- Virtual Button driver got a few fixes to detect mode of 2-in-1 tablet
models
- Intel Speed Select tools update
- Plenty of small cleanups here and there
* tag 'platform-drivers-x86-v5.8-1' of git://git.infradead.org/linux-platform-drivers-x86: (89 commits)
platform/x86: dcdbas: Check SMBIOS for protected buffer address
platform/x86: asus_wmi: Reserve more space for struct bias_args
platform/x86: intel-vbtn: Only blacklist SW_TABLET_MODE on the 9 / "Laptop" chasis-type
platform/x86: intel-hid: Add a quirk to support HP Spectre X2 (2015)
platform/x86: touchscreen_dmi: Update Trekstor Twin 10.1 entry
platform/x86: touchscreen_dmi: Add info for the Trekstor Yourbook C11B
platform/x86: hp-wmi: Introduce HPWMI_POWER_FW_OR_HW as convenient shortcut
platform/x86: hp-wmi: Convert simple_strtoul() to kstrtou32()
platform/x86: hp-wmi: Refactor postcode_store() to follow standard patterns
platform/x86: acerhdf: replace space by * in modalias
platform/x86: ISST: Increase timeout
tools/power/x86/intel-speed-select: Fix invalid core mask
tools/power/x86/intel-speed-select: Increase CPU count
tools/power/x86/intel-speed-select: Fix json perf-profile output output
platform/x86: dell-wmi: Ignore keyboard attached / detached events
platform/x86: dell-laptop: don't register micmute LED if there is no token
platform/x86: thinkpad_acpi: Replace custom approach by kstrtoint()
platform/x86: thinkpad_acpi: Use strndup_user() in dispatch_proc_write()
platform/x86: thinkpad_acpi: Replace next_cmd(&buf) with strsep(&buf, ",")
platform/x86: intel-vbtn: Detect switch position before registering the input-device
...
set from Mauro toward the completion of the RST conversion. I *really*
hope we are getting close to the end of this. Meanwhile, those patches
reach pretty far afield to update document references around the tree;
there should be no actual code changes there. There will be, alas, more of
the usual trivial merge conflicts.
Beyond that we have more translations, improvements to the sphinx
scripting, a number of additions to the sysctl documentation, and lots of
fixes.
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Merge tag 'docs-5.8' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"A fair amount of stuff this time around, dominated by yet another
massive set from Mauro toward the completion of the RST conversion. I
*really* hope we are getting close to the end of this. Meanwhile,
those patches reach pretty far afield to update document references
around the tree; there should be no actual code changes there. There
will be, alas, more of the usual trivial merge conflicts.
Beyond that we have more translations, improvements to the sphinx
scripting, a number of additions to the sysctl documentation, and lots
of fixes"
* tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits)
Documentation: fixes to the maintainer-entry-profile template
zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst
tracing: Fix events.rst section numbering
docs: acpi: fix old http link and improve document format
docs: filesystems: add info about efivars content
Documentation: LSM: Correct the basic LSM description
mailmap: change email for Ricardo Ribalda
docs: sysctl/kernel: document unaligned controls
Documentation: admin-guide: update bug-hunting.rst
docs: sysctl/kernel: document ngroups_max
nvdimm: fixes to maintainter-entry-profile
Documentation/features: Correct RISC-V kprobes support entry
Documentation/features: Refresh the arch support status files
Revert "docs: sysctl/kernel: document ngroups_max"
docs: move locking-specific documents to locking/
docs: move digsig docs to the security book
docs: move the kref doc into the core-api book
docs: add IRQ documentation at the core-api book
docs: debugging-via-ohci1394.txt: add it to the core-api book
docs: fix references for ipmi.rst file
...
When SYNC_STATE_ONLY support was added in commit 05ef983e0d ("driver
core: Add device link support for SYNC_STATE_ONLY flag"),
SYNC_STATE_ONLY links were treated similar to STATELESS links in terms
of not blocking consumer probe if the supplier hasn't probed yet.
That caused a SYNC_STATE_ONLY device link's status to not get updated.
Since SYNC_STATE_ONLY device link is no longer useful once the
consumer probes, commit 21c27f0658 ("driver core: Fix
SYNC_STATE_ONLY device link implementation") addresses the status
update issue by deleting the SYNC_STATE_ONLY device link instead of
complicating the status update code.
However, there are still some cases where we need to update the status
of a SYNC_STATE_ONLY device link. This is because a SYNC_STATE_ONLY
device link can later get converted into a normal MANAGED device link
when a normal MANAGED device link is created between a supplier and
consumer that already have a SYNC_STATE_ONLY device link between them.
If a SYNC_STATE_ONLY device link's status isn't maintained correctly
till it's converted to a normal MANAGED device link, then the normal
MANAGED device link will end up with a wrong link status. This can cause
a warning stack trace[1] when the consumer device probes successfully.
This commit fixes the SYNC_STATE_ONLY device link status update issue
where it wouldn't transition correctly from DL_STATE_DORMANT or
DL_STATE_AVAILABLE to DL_STATE_CONSUMER_PROBE. It also resets the status
back to DL_STATE_DORMANT or DL_STATE_AVAILABLE if the consumer probe
fails.
[1] - https://lore.kernel.org/lkml/20200522204120.3b3c9ed6@apollo/
Fixes: 05ef983e0d ("driver core: Add device link support for SYNC_STATE_ONLY flag")
Fixes: 21c27f0658 ("driver core: Fix SYNC_STATE_ONLY device link implementation")
Reported-by: Michael Walle <michael@walle.cc>
Tested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Reviewed-by: Rafael J. Wysocki <rrafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20200526220928.49939-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
That variable is no longer necessary. Remove it and also fix a minor
typo in comments.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200520034824.79049-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 21c27f0658 ("driver core: Fix SYNC_STATE_ONLY device link
implementation") didn't completely fix STATELESS + SYNC_STATE_ONLY
handling.
What looks like an optimization in that commit is actually a bug that
causes an if condition to always take the else path. This prevents
reordering of devices in the dpm_list when a DL_FLAG_STATELESS device
link is create on top of an existing DL_FLAG_SYNC_STATE_ONLY device
link.
Fixes: 21c27f0658 ("driver core: Fix SYNC_STATE_ONLY device link implementation")
Signed-off-by: Saravana Kannan <saravanak@google.com>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20200520043626.181820-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When SYNC_STATE_ONLY support was added in commit 05ef983e0d ("driver
core: Add device link support for SYNC_STATE_ONLY flag"),
device_link_add() incorrectly skipped adding the new SYNC_STATE_ONLY
device link to the supplier's and consumer's "device link" list.
This causes multiple issues:
- The device link is lost forever from driver core if the caller
didn't keep track of it (caller typically isn't expected to). This is
a memory leak.
- The device link is also never visible to any other code path after
device_link_add() returns.
If we fix the "device link" list handling, that exposes a bunch of
issues.
1. The device link "status" state management code rightfully doesn't
handle the case where a DL_FLAG_MANAGED device link exists between a
supplier and consumer, but the consumer manages to probe successfully
before the supplier. The addition of DL_FLAG_SYNC_STATE_ONLY links break
this assumption. This causes device_links_driver_bound() to throw a
warning when this happens.
Since DL_FLAG_SYNC_STATE_ONLY device links are mainly used for creating
proxy device links for child device dependencies and aren't useful once
the consumer device probes successfully, this patch just deletes
DL_FLAG_SYNC_STATE_ONLY device links once its consumer device probes.
This way, we avoid the warning, free up some memory and avoid
complicating the device links "status" state management code.
2. Creating a DL_FLAG_STATELESS device link between two devices that
already have a DL_FLAG_SYNC_STATE_ONLY device link will result in the
DL_FLAG_STATELESS flag not getting set correctly. This patch also fixes
this.
Lastly, this patch also fixes minor whitespace issues.
Cc: stable@vger.kernel.org
Fixes: 05ef983e0d ("driver core: Add device link support for SYNC_STATE_ONLY flag")
Signed-off-by: Saravana Kannan <saravanak@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20200519063000.128819-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The amount of time spent parsing fwnodes of devices can become really
high if the devices are added in an non-ideal order. Worst case can be
O(N^2) when N devices are added. But this can be optimized to O(N) by
adding all the devices and then parsing all their fwnodes in one batch.
This commit adds fw_devlink_pause() and fw_devlink_resume() to allow
doing this.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200515053500.215929-4-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 4dbe191c04 ("driver core: Add device links from fwnode only for
the primary device") skipped linking a fwnode's secondary device to
the suppliers listed in its fwnode.
However, a fwnode's secondary device can't be found using
get_dev_from_fwnode(). So, there's no point in trying to see if devices
waiting for suppliers might want to link to a fwnode's secondary device.
This commit removes that unnecessary step for devices that aren't a
fwnode's primary device and also moves the code to a more appropriate
part of the file.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200515053500.215929-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We want the driver core fixes in here and this resolves a merge issue
with drivers/base/dd.c
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All external users of device_create_vargs are gone, so remove it and
open code it in the only caller.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When commit 8375e74f2b ("driver core: Add fw_devlink kernel
commandline option") added fw_devlink, it didn't implement "permissive"
mode correctly.
That commit got the device links flags correct to make sure unprobed
suppliers don't block the probing of a consumer. However, if a consumer
is waiting for mandatory suppliers to register, that could still block a
consumer from probing.
This commit fixes that by making sure in permissive mode, all suppliers
to a consumer are treated as a optional suppliers. So, even if a
consumer is waiting for suppliers to register and link itself (using the
DL_FLAG_SYNC_STATE_ONLY flag) to the supplier, the consumer is never
blocked from probing.
Fixes: 8375e74f2b ("driver core: Add fw_devlink kernel commandline option")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20200331022832.209618-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some drivers when compiled as modules may need to set secondary firmware node.
Export set_secondary_fwnode() to make it possible without code duplication.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Pull networking updates from David Miller:
"Highlights:
1) Fix the iwlwifi regression, from Johannes Berg.
2) Support BSS coloring and 802.11 encapsulation offloading in
hardware, from John Crispin.
3) Fix some potential Spectre issues in qtnfmac, from Sergey
Matyukevich.
4) Add TTL decrement action to openvswitch, from Matteo Croce.
5) Allow paralleization through flow_action setup by not taking the
RTNL mutex, from Vlad Buslov.
6) A lot of zero-length array to flexible-array conversions, from
Gustavo A. R. Silva.
7) Align XDP statistics names across several drivers for consistency,
from Lorenzo Bianconi.
8) Add various pieces of infrastructure for offloading conntrack, and
make use of it in mlx5 driver, from Paul Blakey.
9) Allow using listening sockets in BPF sockmap, from Jakub Sitnicki.
10) Lots of parallelization improvements during configuration changes
in mlxsw driver, from Ido Schimmel.
11) Add support to devlink for generic packet traps, which report
packets dropped during ACL processing. And use them in mlxsw
driver. From Jiri Pirko.
12) Support bcmgenet on ACPI, from Jeremy Linton.
13) Make BPF compatible with RT, from Thomas Gleixnet, Alexei
Starovoitov, and your's truly.
14) Support XDP meta-data in virtio_net, from Yuya Kusakabe.
15) Fix sysfs permissions when network devices change namespaces, from
Christian Brauner.
16) Add a flags element to ethtool_ops so that drivers can more simply
indicate which coalescing parameters they actually support, and
therefore the generic layer can validate the user's ethtool
request. Use this in all drivers, from Jakub Kicinski.
17) Offload FIFO qdisc in mlxsw, from Petr Machata.
18) Support UDP sockets in sockmap, from Lorenz Bauer.
19) Fix stretch ACK bugs in several TCP congestion control modules,
from Pengcheng Yang.
20) Support virtual functiosn in octeontx2 driver, from Tomasz
Duszynski.
21) Add region operations for devlink and use it in ice driver to dump
NVM contents, from Jacob Keller.
22) Add support for hw offload of MACSEC, from Antoine Tenart.
23) Add support for BPF programs that can be attached to LSM hooks,
from KP Singh.
24) Support for multiple paths, path managers, and counters in MPTCP.
From Peter Krystad, Paolo Abeni, Florian Westphal, Davide Caratti,
and others.
25) More progress on adding the netlink interface to ethtool, from
Michal Kubecek"
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2121 commits)
net: ipv6: rpl_iptunnel: Fix potential memory leak in rpl_do_srh_inline
cxgb4/chcr: nic-tls stats in ethtool
net: dsa: fix oops while probing Marvell DSA switches
net/bpfilter: remove superfluous testing message
net: macb: Fix handling of fixed-link node
net: dsa: ksz: Select KSZ protocol tag
netdevsim: dev: Fix memory leak in nsim_dev_take_snapshot_write
net: stmmac: add EHL 2.5Gbps PCI info and PCI ID
net: stmmac: add EHL PSE0 & PSE1 1Gbps PCI info and PCI ID
net: stmmac: create dwmac-intel.c to contain all Intel platform
net: dsa: bcm_sf2: Support specifying VLAN tag egress rule
net: dsa: bcm_sf2: Add support for matching VLAN TCI
net: dsa: bcm_sf2: Move writing of CFP_DATA(5) into slicing functions
net: dsa: bcm_sf2: Check earlier for FLOW_EXT and FLOW_MAC_EXT
net: dsa: bcm_sf2: Disable learning for ASP port
net: dsa: b53: Deny enslaving port 7 for 7278 into a bridge
net: dsa: b53: Prevent tagged VLAN on port 7 for 7278
net: dsa: b53: Restore VLAN entries upon (re)configuration
net: dsa: bcm_sf2: Fix overflow checks
hv_netvsc: Remove unnecessary round_up for recv_completion_cnt
...
This reverts commit c442a0d187 as it
breaks some of the Raspberry Pi devices. Marek writes:
This patch has just landed in linux-next 20200326. Sadly it
breaks booting of the Raspberry Pi3b and Pi4 boards, either in
32bit or 64bit mode. There is no warning nor panic message, just
a silent freeze. The last message shown on the earlycon is:
[ 0.893217] Serial: 8250/16550 driver, 1 ports, IRQ sharing enabled
so revert it for now and let's try again and add it to linux-next after
5.7-rc1 is out so that we can try to get more debugging/testing
happening.
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Saravana Kannan <saravanak@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Set fw_devlink to "permissive" behavior by default so that device links
are automatically created (with DL_FLAG_SYNC_STATE_ONLY) by scanning the
firmware.
This ensures suppliers get their sync_state() calls only after all their
consumers have probed successfully. Without this, suppliers will get
their sync_state() calls at late_initcall_sync() even if their consuer
Ideally, we'd want to set fw_devlink to "on" or "rpm" by default. But
that needs more testing as it's known to break some corner case
drivers/platforms.
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: devicetree@vger.kernel.org
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200321210305.28937-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sometimes, more than one (generally two) device can point to the same
fwnode. However, only one device is set as the fwnode's device
(fwnode->dev) and can be looked up from the fwnode.
Typically, only one of these devices actually have a driver and actually
probe. If we create device links for all these devices, then the
suppliers' of these devices (with the same fwnode) will never get a
sync_state() call because one of their consumer devices will never probe
(because they don't have a driver).
So, create device links only for the device that is considered as the
fwnode's device.
One such example of this is the PCI bridge platform_device and the
corresponding pci_bus device. Both these devices will have the same
fwnode. It's the platform_device that is registered first and is set as
the fwnode's device. Also the platform_device is the one that actually
probes. Without this patch none of the suppliers of a PCI bridge
platform_device would get a sync_state() callback.
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-pci@vger.kernel.org
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200321045448.15192-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sparse reports a warning at device_links_write_lock()
warning: context imbalance in evice_links_write_lock()
- wrong count at exit
The root cause is the missing annotation at device_links_write_lock()
Add the missing __acquires(&device_links_srcu) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Link: https://lore.kernel.org/r/20200214204741.94112-19-jbi.octave@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sparse reports a warning at device_links_read_unlock()
warning: warning: context imbalance in device_links_read_unlock()
- unexpected unlock
The root cause is the missing annotation at device_links_read_unlock()
Add the missing __releases(&device_links_srcu) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Link: https://lore.kernel.org/r/20200214204741.94112-20-jbi.octave@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fwnode_operations.add_links allows creating device links from
information provided by firmware.
fwnode_operations.add_links is currently implemented only by
OF/devicetree code and a specific case of efi. However, there's nothing
preventing ACPI or other firmware types from implementing it.
The OF implementation is currently controlled by a kernel commandline
parameter called of_devlink.
Since this feature is generic isn't limited to OF, add a generic
fw_devlink kernel commandline parameter to control this feature across
firmware types.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200222014038.180923-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A previous patch 03324507e6 ("driver core: Allow
fwnode_operations.add_links to differentiate errors") forgot to update
all call sites to fwnode_operations.add_links. This patch fixes that.
Legend:
-> Denotes RHS is an optional/potential supplier for LHS
=> Denotes RHS is a mandatory supplier for LHS
Example:
Device A => Device X
Device A -> Device Y
Before this patch:
1. Device A is added.
2. Device A is marked as waiting for mandatory suppliers
3. Device X is added
4. Device A is left marked as waiting for mandatory suppliers
Step 4 is wrong since all mandatory suppliers of Device A have been
added.
After this patch:
1. Device A is added.
2. Device A is marked as waiting for mandatory suppliers
3. Device X is added
4. Device A is no longer considered as waiting for mandatory suppliers
This is the correct behavior.
Fixes: 03324507e6 ("driver core: Allow fwnode_operations.add_links to differentiate errors")
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200222014038.180923-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A bunch of busy work is done for devices that don't have sync_state()
support. Stop doing the busy work.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200221080510.197337-4-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The initial patch that added sync_state() support didn't handle the case
where a supplier has no consumers. This was because when a device is
successfully bound with a driver, only its suppliers were checked to see
if they are eligible to get a sync_state(). This is not sufficient for
devices that have no consumers but still need to do device state clean
up. So fix this.
Fixes: fc5a251d0f (driver core: Add sync_state driver/bus callback)
Signed-off-by: Saravana Kannan <saravanak@google.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200221080510.197337-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a helper to change the owner of a device's power entries. This
needs to happen when the ownership of a device is changed, e.g. when
moving network devices between network namespaces.
This function will be used to correctly account for ownership changes,
e.g. when moving network devices between network namespaces.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a helper to change the owner of a device's sysfs entries. This
needs to happen when the ownership of a device is changed, e.g. when
moving network devices between network namespaces.
This function will be used to correctly account for ownership changes,
e.g. when moving network devices between network namespaces.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some sync_state() implementations might need to call APIs that in turn
make calls to device link APIs. So, do the sync_state() callbacks
without holding the device link lock.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20191114225646.251277-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When add_links() still has suppliers that it needs to link to in the
future, this patch allows it to differentiate between suppliers that are
needed for probing vs suppliers that are needed for sync_state()
correctness.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20191028220027.251605-4-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Before this change, if a device is waiting on suppliers, it's assumed
that all those suppliers are needed for the device to probe
successfully. This change allows marking a devices as waiting only on
optional suppliers. This allows a device to wait on suppliers (and link
to them as soon as they are available) without preventing the device
from being probed.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20191028220027.251605-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Parent devices might need to create "proxy" device links from themselves
to supplier devices to make sure the supplier devices don't get a
sync_state() before the child consumer devices get a chance to add
device links to the supplier devices.
However, the parent device has no real dependency on the supplier device
and probing, suspend/resume or runtime PM don't need to be affected by
the supplier device. To capture these cases, create a SYNC_STATE_ONLY
device link flag that only affects sync_state() behavior and doesn't
affect probing, suspend/resume or runtime PM.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20191028220027.251605-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It is incorrect to set the cpufreq syscore shutdown callback pointer
to cpufreq_suspend(), because that function cannot be run in the
syscore stage of system shutdown for two reasons: (a) it may attempt
to carry out actions depending on devices that have already been shut
down at that point and (b) the RCU synchronization carried out by it
may not be able to make progress then.
The latter issue has been present since commit 45975c7d21 ("rcu:
Define RCU-sched API in terms of RCU for Tree RCU PREEMPT builds"),
but the former one has been there since commit 90de2a4aa9 ("cpufreq:
suspend cpufreq governors on shutdown") regardless.
Fix that by dropping cpufreq_syscore_ops altogether and making
device_shutdown() call cpufreq_suspend() directly before shutting
down devices, which is along the lines of what system-wide power
management does.
Fixes: 45975c7d21 ("rcu: Define RCU-sched API in terms of RCU for Tree RCU PREEMPT builds")
Fixes: 90de2a4aa9 ("cpufreq: suspend cpufreq governors on shutdown")
Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.0+ <stable@vger.kernel.org> # 4.0+
This sync_state driver/bus callback is called once all the consumers
of a supplier have probed successfully.
This allows the supplier device's driver/bus to sync the supplier
device's state to the software state with the guarantee that all the
consumers are actively managing the resources provided by the supplier
device.
To maintain backwards compatibility and ease transition from existing
frameworks and resource cleanup schemes, late_initcall_sync is the
earliest when the sync_state callback might be called.
There is no upper bound on the time by which the sync_state callback
has to be called. This is because if a consumer device never probes,
the supplier has to maintain its resources in the state left by the
bootloader. For example, if the bootloader leaves the display
backlight at a fixed voltage and the backlight driver is never probed,
you don't want the backlight to ever be turned off after boot up.
Also, when multiple devices are added after kernel init, some
suppliers could be added before their consumer devices get added. In
these instances, the supplier devices could get their sync_state
callback called right after they probe because the consumers devices
haven't had a chance to create device links to the suppliers.
To handle this correctly, this change also provides APIs to
pause/resume sync state callbacks so that when multiple devices are
added, their sync_state callback evaluation can be postponed to happen
after all of them are added.
kbuild test robot reported missing documentation for device.state_synced
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20190904211126.47518-5-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The firmware corresponding to a device (dev.fwnode) might be able to
provide functional dependency information between a device and its
supplier and consumer devices. Tracking this functional dependency
allows optimizing device probe order and informing a supplier when all
its consumers have probed (and thereby actively managing their
resources).
The existing device links feature allows tracking and using
supplier-consumer relationships. So, this patch adds the add_links()
fwnode callback to allow firmware to create device links for each
device as the device is added.
However, when consumer devices are added, they might not have a supplier
device to link to despite needing mandatory resources/functionality from
one or more suppliers. A waiting_for_suppliers list is created to track
such consumers and retry linking them when new devices get added.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20190904211126.47518-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's often useful to look up a device that corresponds to a fwnode. So
add an API to do that irrespective of the bus on which the device has
been added to.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20190904211126.47518-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Saravana Kannan