linux-stable.git/drivers/watchdog, branch v6.14

Merge tag 'linux-watchdog-6.14-rc1' of git://www.linux-watchdog.org/linux-watchdog

2025-01-26T00:19:10+00:00

Pull watchdog updates from Wim Van Sebroeck:

 - Add Qualcomm IPQ5424 DT binding

 - da9052_wdt: add support for bootstatus bits

 - Other small fixes and improvements

* tag 'linux-watchdog-6.14-rc1' of git://www.linux-watchdog.org/linux-watchdog:
  dt-bindings: watchdog: Document Qualcomm IPQ5424
  watchdog: rti_wdt: Fix an OF node leak in rti_wdt_probe()
  watchdog: max77620: fix excess field in kerneldoc
  watchdog: sp805_wdt: Drop documentation of non-existent `status` member
  watchdog: rzv2h_wdt: Use local `dev` pointer in probe
  watchdog: da9052_wdt: add support for bootstatus bits
  watchdog: sp805: Report correct timeleft at maximum
  watchdog: rti: Fix off-by-one in heartbeat recovery

Merge tag 'kthread-for-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks

2025-01-22T01:10:05+00:00

Pull kthread updates from Frederic Weisbecker:
 "Kthreads affinity follow either of 4 existing different patterns:

   1) Per-CPU kthreads must stay affine to a single CPU and never
      execute relevant code on any other CPU. This is currently handled
      by smpboot code which takes care of CPU-hotplug operations.
      Affinity here is a correctness constraint.

   2) Some kthreads _have_ to be affine to a specific set of CPUs and
      can't run anywhere else. The affinity is set through
      kthread_bind_mask() and the subsystem takes care by itself to
      handle CPU-hotplug operations. Affinity here is assumed to be a
      correctness constraint.

   3) Per-node kthreads _prefer_ to be affine to a specific NUMA node.
      This is not a correctness constraint but merely a preference in
      terms of memory locality. kswapd and kcompactd both fall into this
      category. The affinity is set manually like for any other task and
      CPU-hotplug is supposed to be handled by the relevant subsystem so
      that the task is properly reaffined whenever a given CPU from the
      node comes up. Also care should be taken so that the node affinity
      doesn't cross isolated (nohz_full) cpumask boundaries.

   4) Similar to the previous point except kthreads have a _preferred_
      affinity different than a node. Both RCU boost kthreads and RCU
      exp kworkers fall into this category as they refer to "RCU nodes"
      from a distinctly distributed tree.

  Currently the preferred affinity patterns (3 and 4) have at least 4
  identified users, with more or less success when it comes to handle
  CPU-hotplug operations and CPU isolation. Each of which do it in its
  own ad-hoc way.

  This is an infrastructure proposal to handle this with the following
  API changes:

   - kthread_create_on_node() automatically affines the created kthread
     to its target node unless it has been set as per-cpu or bound with
     kthread_bind[_mask]() before the first wake-up.

   - kthread_affine_preferred() is a new function that can be called
     right after kthread_create_on_node() to specify a preferred
     affinity different than the specified node.

  When the preferred affinity can't be applied because the possible
  targets are offline or isolated (nohz_full), the kthread is affine to
  the housekeeping CPUs (which means to all online CPUs most of the time
  or only the non-nohz_full CPUs when nohz_full= is set).

  kswapd, kcompactd, RCU boost kthreads and RCU exp kworkers have been
  converted, along with a few old drivers.

  Summary of the changes:

   - Consolidate a bunch of ad-hoc implementations of
     kthread_run_on_cpu()

   - Introduce task_cpu_fallback_mask() that defines the default last
     resort affinity of a task to become nohz_full aware

   - Add some correctness check to ensure kthread_bind() is always
     called before the first kthread wake up.

   - Default affine kthread to its preferred node.

   - Convert kswapd / kcompactd and remove their halfway working ad-hoc
     affinity implementation

   - Implement kthreads preferred affinity

   - Unify kthread worker and kthread API's style

   - Convert RCU kthreads to the new API and remove the ad-hoc affinity
     implementation"

* tag 'kthread-for-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks:
  kthread: modify kernel-doc function name to match code
  rcu: Use kthread preferred affinity for RCU exp kworkers
  treewide: Introduce kthread_run_worker[_on_cpu]()
  kthread: Unify kthread_create_on_cpu() and kthread_create_worker_on_cpu() automatic format
  rcu: Use kthread preferred affinity for RCU boost
  kthread: Implement preferred affinity
  mm: Create/affine kswapd to its preferred node
  mm: Create/affine kcompactd to its preferred node
  kthread: Default affine kthread to its preferred NUMA node
  kthread: Make sure kthread hasn't started while binding it
  sched,arm64: Handle CPU isolation on last resort fallback rq selection
  arm64: Exclude nohz_full CPUs from 32bits el0 support
  lib: test_objpool: Use kthread_run_on_cpu()
  kallsyms: Use kthread_run_on_cpu()
  soc/qman: test: Use kthread_run_on_cpu()
  arm/bL_switcher: Use kthread_run_on_cpu()

treewide: Introduce kthread_run_worker[_on_cpu]()

2025-01-08T17:15:03+00:00

kthread_create() creates a kthread without running it yet. kthread_run()
creates a kthread and runs it.

On the other hand, kthread_create_worker() creates a kthread worker and
runs it.

This difference in behaviours is confusing. Also there is no way to
create a kthread worker and affine it using kthread_bind_mask() or
kthread_affine_preferred() before starting it.

Consolidate the behaviours and introduce kthread_run_worker[_on_cpu]()
that behaves just like kthread_run(). kthread_create_worker[_on_cpu]()
will now only create a kthread worker without starting it.

Signed-off-by: Frederic Weisbecker 
Signed-off-by: Dan Carpenter

watchdog: rti_wdt: Fix an OF node leak in rti_wdt_probe()

2025-01-06T18:38:07+00:00

rti_wdt_probe() does not release the OF node reference obtained by
of_parse_phandle(). Add a of_node_put() call.

This was found by an experimental verification tool that I am
developing. Due to the lack of the actual device, no runtime test was
able to be performed.

Fixes: f20ca595ae23 ("watchdog:rit_wdt: Add support for WDIOF_CARDRESET")
Signed-off-by: Joe Hattori 
Reviewed-by: Guenter Roeck 
Link: https://lore.kernel.org/r/20250105111718.4184192-1-joe@pf.is.s.u-tokyo.ac.jp
Signed-off-by: Guenter Roeck 
Signed-off-by: Wim Van Sebroeck

watchdog: max77620: fix excess field in kerneldoc

2025-01-06T18:38:07+00:00

The wdt_info does not exist in the struct being documented.

Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202412281555.YMBF9azh-lkp@intel.com/
Signed-off-by: Luca Ceresoli 
Reviewed-by: Guenter Roeck 
Link: https://lore.kernel.org/r/20241230-max77620_wdt-kerneldoc-fix-v1-1-8a3211818993@bootlin.com
Signed-off-by: Guenter Roeck 
Signed-off-by: Wim Van Sebroeck

watchdog: sp805_wdt: Drop documentation of non-existent `status` member

2025-01-06T18:37:52+00:00

Remove the documentation for the `status` field in the `sp805_wdt`
structure, as the field does not exist.

Signed-off-by: Lad Prabhakar 
Reviewed-by: Guenter Roeck 
Link: https://lore.kernel.org/r/20241213192858.916377-1-prabhakar.csengg@gmail.com
Signed-off-by: Guenter Roeck 
Signed-off-by: Wim Van Sebroeck

watchdog: rzv2h_wdt: Use local `dev` pointer in probe

2025-01-06T18:37:51+00:00

Update the `rzv2h_wdt_probe()` function to consistently use the local
`dev` pointer, which is already extracted from `&pdev->dev`.

Signed-off-by: Lad Prabhakar 
Reviewed-by: Guenter Roeck 
Link: https://lore.kernel.org/r/20241213171157.898934-1-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Guenter Roeck 
Signed-off-by: Wim Van Sebroeck

watchdog: da9052_wdt: add support for bootstatus bits

2025-01-06T18:37:51+00:00

Enable support for these bootstatus bits:
    WDIOF_CARDRESET
    WDIOF_OVERHEAT
    WDIOF_POWERUNDER

Signed-off-by: Marcus Folkesson 
Reviewed-by: Guenter Roeck 
Link: https://lore.kernel.org/r/20241210-da9052-wdt-v2-2-95a5756e9ac8@gmail.com
Signed-off-by: Guenter Roeck 
Signed-off-by: Wim Van Sebroeck

watchdog: sp805: Report correct timeleft at maximum

2025-01-06T18:37:50+00:00

sp805_wdt::load_val is of type unsigned int. When the interrupt is
inactive wdt_timeleft adds one to the value, and then adds that to the
value used to calculate the time remaining. Unfortunately it's not
unlikely that load_val contains LOAD_MAX, which is 0xFFFFFFFF and wraps
to zero when one is added to it, resulting in the time left being
understated by about 21.7s. Fix this by ensuring the addition happens as
64-bit.

Signed-off-by: Mike Crowe 
Reviewed-by: Guenter Roeck 
Link: https://lore.kernel.org/r/20241203095744.3001795-1-mac@mcrowe.com
Signed-off-by: Guenter Roeck 
Signed-off-by: Wim Van Sebroeck

watchdog: rti: Fix off-by-one in heartbeat recovery

2025-01-06T18:37:49+00:00

According to AM62x TRM WDT period is (RTIDWDPRLD + 1) * (2^13) / RTICLK1,
Fix the heartbeat recovery. In practice this doesn't affect rounded
heatbeat in seconds, but it does correct 4% of error in milliseconds,
for, say, default 60s heartbeat. This affects last_ping calculation.

Signed-off-by: Alexander Sverdlin 
Reviewed-by: Guenter Roeck 
Link: https://lore.kernel.org/r/20241126073646.126752-1-alexander.sverdlin@siemens.com
Signed-off-by: Guenter Roeck 
Signed-off-by: Wim Van Sebroeck