linux-stable.git/drivers/base, branch linux-6.8.y

regmap: Add regmap_read_bypassed()

2024-05-17T10:14:26+00:00

[ Upstream commit 70ee853eec5693fefd8348a2b049d9cb83362e58 ]

Add a regmap_read_bypassed() to allow reads from the hardware registers
while the regmap is in cache-only mode.

A typical use for this is to keep the cache in cache-only mode until
the hardware has reached a valid state, but one or more status registers
must be polled to determine when this state is reached.

For example, firmware download on the cs35l56 can take several seconds if
there are multiple amps sharing limited bus bandwidth. This is too long
to block in probe() so it is done as a background task. The device must
be soft-reset to reboot the firmware and during this time the registers are
not accessible, so the cache should be in cache-only. But the driver must
poll a register to detect when reboot has completed.

Signed-off-by: Richard Fitzgerald 
Fixes: 8a731fd37f8b ("ASoC: cs35l56: Move utility functions to shared file")
Link: https://msgid.link/r/20240408101803.43183-2-rf@opensource.cirrus.com
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

base/node / ACPI: Enumerate node access class for 'struct access_coordinate'

2024-04-17T09:23:29+00:00

[ Upstream commit 11270e526276ffad4c4237acb393da82a3287487 ]

Both generic node and HMAT handling code have been using magic numbers to
indicate access classes for 'struct access_coordinate'. Introduce enums to
enumerate the access0 and access1 classes shared by the two subsystems.
Update the function parameters and callers as appropriate to utilize the
new enum.

Access0 is named to ACCESS_COORDINATE_LOCAL in order to indicate that the
access class is for 'struct access_coordinate' between a target node and
the nearest initiator node.

Access1 is named to ACCESS_COORDINATE_CPU in order to indicate that the
access class is for 'struct access_coordinate' between a target node and
the nearest CPU node.

Cc: Greg Kroah-Hartman 
Cc: Rafael J. Wysocki 
Reviewed-by: Jonathan Cameron 
Tested-by: Jonathan Cameron 
Acked-by: Greg Kroah-Hartman 
Signed-off-by: Dave Jiang 
Link: https://lore.kernel.org/r/20240308220055.2172956-3-dave.jiang@intel.com
Signed-off-by: Dan Williams 
Stable-dep-of: 592780b8391f ("cxl: Fix retrieving of access_coordinates in PCIe path")
Signed-off-by: Sasha Levin

driver core: Introduce device_link_wait_removal()

2024-04-10T14:38:18+00:00

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 
Tested-by: Luca Ceresoli 
Reviewed-by: Nuno Sa 
Reviewed-by: Saravana Kannan 
Acked-by: Greg Kroah-Hartman 
Link: https://lore.kernel.org/r/20240325152140.198219-2-herve.codina@bootlin.com
Signed-off-by: Rob Herring 
Signed-off-by: Greg Kroah-Hartman

regmap: maple: Fix uninitialized symbol 'ret' warnings

2024-04-10T14:38:12+00:00

[ Upstream commit eaa03486d932572dfd1c5f64f9dfebe572ad88c0 ]

Fix warnings reported by smatch by initializing local 'ret' variable
to 0.

drivers/base/regmap/regcache-maple.c:186 regcache_maple_drop()
error: uninitialized symbol 'ret'.
drivers/base/regmap/regcache-maple.c:290 regcache_maple_sync()
error: uninitialized symbol 'ret'.

Signed-off-by: Richard Fitzgerald 
Fixes: f033c26de5a5 ("regmap: Add maple tree based register cache")
Link: https://lore.kernel.org/r/20240329144630.1965159-1-rf@opensource.cirrus.com
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

regmap: maple: Fix cache corruption in regcache_maple_drop()

2024-04-10T14:38:10+00:00

[ Upstream commit 00bb549d7d63a21532e76e4a334d7807a54d9f31 ]

When keeping the upper end of a cache block entry, the entry[] array
must be indexed by the offset from the base register of the block,
i.e. max - mas.index.

The code was indexing entry[] by only the register address, leading
to an out-of-bounds access that copied some part of the kernel
memory over the cache contents.

This bug was not detected by the regmap KUnit test because it only
tests with a block of registers starting at 0, so mas.index == 0.

Signed-off-by: Richard Fitzgerald 
Fixes: f033c26de5a5 ("regmap: Add maple tree based register cache")
Link: https://msgid.link/r/20240327114406.976986-1-rf@opensource.cirrus.com
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

PM: sleep: wakeirq: fix wake irq warning in system suspend

2024-04-03T13:32:11+00:00

[ Upstream commit e7a7681c859643f3f2476b2a28a494877fd89442 ]

When driver uses pm_runtime_force_suspend() as the system suspend callback
function and registers the wake irq with reverse enable ordering, the wake
irq will be re-enabled when entering system suspend, triggering an
'Unbalanced enable for IRQ xxx' warning. In this scenario, the call
sequence during system suspend is as follows:
  suspend_devices_and_enter()
    -> dpm_suspend_start()
      -> dpm_run_callback()
        -> pm_runtime_force_suspend()
          -> dev_pm_enable_wake_irq_check()
          -> dev_pm_enable_wake_irq_complete()

    -> suspend_enter()
      -> dpm_suspend_noirq()
        -> device_wakeup_arm_wake_irqs()
          -> dev_pm_arm_wake_irq()

To fix this issue, complete the setting of WAKE_IRQ_DEDICATED_ENABLED flag
in dev_pm_enable_wake_irq_complete() to avoid redundant irq enablement.

Fixes: 8527beb12087 ("PM: sleep: wakeirq: fix wake irq arming")
Reviewed-by: Dhruva Gole 
Signed-off-by: Qingliang Li 
Reviewed-by: Johan Hovold 
Cc: 5.16+  # 5.16+
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

x86/rfds: Mitigate Register File Data Sampling (RFDS)

2024-03-15T14:48:13+00:00

commit 8076fcde016c9c0e0660543e67bff86cb48a7c9c upstream.

RFDS is a CPU vulnerability that may allow userspace to infer kernel
stale data previously used in floating point registers, vector registers
and integer registers. RFDS only affects certain Intel Atom processors.

Intel released a microcode update that uses VERW instruction to clear
the affected CPU buffers. Unlike MDS, none of the affected cores support
SMT.

Add RFDS bug infrastructure and enable the VERW based mitigation by
default, that clears the affected buffers just before exiting to
userspace. Also add sysfs reporting and cmdline parameter
"reg_file_data_sampling" to control the mitigation.

For details see:
Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst

Signed-off-by: Pawan Gupta 
Signed-off-by: Dave Hansen 
Reviewed-by: Thomas Gleixner 
Acked-by: Josh Poimboeuf 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'driver-core-6.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2024-02-17T16:56:41+00:00

Pull driver core fixes from Greg KH:
 "Here are some driver core fixes, a kobject fix, and a documentation
  update for 6.8-rc5. In detail these changes are:

   - devlink fixes for reported issues with 6.8-rc1

   - topology scheduling regression fix that has been reported by many

   - kobject loosening of checks change in -rc1 is now reverted as some
     codepaths seemed to need the checks

   - documentation update for the CVE process. Has been reviewed by
     many, the last minute change to the document was to bring the .rst
     format back into the the new style rules, the contents did not
     change.

  All of these, except for the documentation update, have been in
  linux-next for over a week. The documentation update has been reviewed
  for weeks by a group of developers, and in public for a week and the
  wording has stabilized for now. If future changes are needed, we can
  do so before 6.8-final is out (or anytime after that)"

* tag 'driver-core-6.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  Documentation: Document the Linux Kernel CVE process
  Revert "kobject: Remove redundant checks for whether ktype is NULL"
  driver core: fw_devlink: Improve logs for cycle detection
  driver core: fw_devlink: Improve detection of overlapping cycles
  driver core: Fix device_link_flag_is_sync_state_only()
  topology: Set capacity_freq_ref in all cases

regmap: kunit: Ensure that changed bytes are actually different

2024-02-12T13:55:51+00:00

During the cache sync test we verify that values we expect to have been
written only to the cache do not appear in the hardware. This works most
of the time but since we randomly generate both the original and new values
there is a low probability that these values may actually be the same.
Wrap get_random_bytes() to ensure that the values are different, there
are other tests which should have similar verification that we actually
changed something.

While we're at it refactor the test to use three changed values rather
than attempting to use one of them twice, that just complicates checking
that our new values are actually new.

We use random generation to try to avoid data dependencies in the tests.

Reported-by: Guenter Roeck 
Reviewed-by: Guenter Roeck 
Tested-by: Guenter Roeck 
Signed-off-by: Mark Brown 
Link: https://msgid.link/r/20240211-regmap-kunit-random-change-v3-1-e387a9ea4468@kernel.org
Signed-off-by: Mark Brown

regmap: kunit: fix raw noinc write test wrapping

2024-02-07T11:17:11+00:00

The raw noinc write test places a known value in the register following
the noinc register to verify that it is not disturbed by the noinc
write. This test ensures this value is distinct by adding 100 to the
second element of the noinc write data.

The regmap registers are 16-bit, while the test value is stored in an
unsigned int. Therefore, adding 100 may cause the register to wrap while
the test value does not, causing the test to fail. This patch fixes this
by changing val_test and val_last from unsigned int to u16.

Signed-off-by: Ben Wolsieffer 
Reported-by: Guenter Roeck 
Closes: https://lore.kernel.org/linux-kernel/745d3a11-15bc-48b6-84c8-c8761c943bed@roeck-us.net/T/
Tested-by: Guenter Roeck 
Link: https://lore.kernel.org/r/20240206151004.1636761-2-ben.wolsieffer@hefring.com
Signed-off-by: Mark Brown