linux.git/drivers/powercap, branch v6.12.61

powercap: dtpm_cpu: Fix NULL pointer dereference in get_pd_power_uw()

2025-08-15T10:13:36+00:00

[ Upstream commit 46dc57406887dd02565cb264224194a6776d882b ]

The get_pd_power_uw() function can crash with a NULL pointer dereference
when em_cpu_get() returns NULL. This occurs when a CPU becomes impossible
during runtime, causing get_cpu_device() to return NULL, which propagates
through em_cpu_get() and leads to a crash when em_span_cpus() dereferences
the NULL pointer.

Add a NULL check after em_cpu_get() and return 0 if unavailable,
matching the existing fallback behavior in __dtpm_cpu_setup().

Fixes: eb82bace8931 ("powercap/drivers/dtpm: Scale the power with the load")
Signed-off-by: Sivan Zohar-Kotzer 
Link: https://patch.msgid.link/20250701221355.96916-1-sivany32@gmail.com
[ rjw: Drop an excess empty code line ]
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

powercap: intel_rapl: Do not change CLAMPING bit if ENABLE bit cannot be changed

2025-07-10T14:05:12+00:00

commit 964209202ebe1569c858337441e87ef0f9d71416 upstream.

PL1 cannot be disabled on some platforms. The ENABLE bit is still set
after software clears it. This behavior leads to a scenario where, upon
user request to disable the Power Limit through the powercap sysfs, the
ENABLE bit remains set while the CLAMPING bit is inadvertently cleared.

According to the Intel Software Developer's Manual, the CLAMPING bit,
"When set, allows the processor to go below the OS requested P states in
order to maintain the power below specified Platform Power Limit value."

Thus this means the system may operate at higher power levels than
intended on such platforms.

Enhance the code to check ENABLE bit after writing to it, and stop
further processing if ENABLE bit cannot be changed.

Reported-by: Srinivas Pandruvada 
Fixes: 2d281d8196e3 ("PowerCap: Introduce Intel RAPL power capping driver")
Cc: All applicable 
Signed-off-by: Zhang Rui 
Link: https://patch.msgid.link/20250619071340.384782-1-rui.zhang@intel.com
[ rjw: Use str_enabled_disabled() instead of open-coded equivalent ]
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

powercap: call put_device() on an error path in powercap_register_control_type()

2025-03-22T19:54:14+00:00

[ Upstream commit 93c66fbc280747ea700bd6199633d661e3c819b3 ]

powercap_register_control_type() calls device_register(), but does not
release the refcount of the device when it fails.

Call put_device() before returning an error to balance the refcount.

Since the kfree(control_type) will be done by powercap_release(), remove
the lines in powercap_register_control_type() before returning the error.

This bug was found by an experimental verifier that I am developing.

Signed-off-by: Joe Hattori 
Link: https://patch.msgid.link/20250110010554.1583411-1-joe@pf.is.s.u-tokyo.ac.jp
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

powercap: dtpm_devfreq: Fix error check against dev_pm_qos_add_request()

2024-10-21T11:23:06+00:00

The caller of the function dev_pm_qos_add_request() checks again a non
zero value but dev_pm_qos_add_request() can return '1' if the request
already exists. Therefore, the setup function fails while the QoS
request actually did not failed.

Fix that by changing the check against a negative value like all the
other callers of the function.

Fixes: e44655617317 ("powercap/drivers/dtpm: Add dtpm devfreq with energy model support")
Signed-off-by: Yuan Can 
Reviewed-by: Lukasz Luba 
Link: https://patch.msgid.link/20241018021205.46460-1-yuancan@huawei.com
[ rjw: Subject edit ]
Signed-off-by: Rafael J. Wysocki

powercap: intel_rapl_msr: Add PL4 support for ArrowLake-H

2024-10-16T20:34:03+00:00

Add ArrowLake-H to the list of processors where PL4 is supported.

Signed-off-by: Srinivas Pandruvada 
Link: https://patch.msgid.link/20241016154851.1293654-1-srinivas.pandruvada@linux.intel.com
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki

powercap: intel_rapl_msr: Add PL4 support for Arrowlake-U

2024-10-08T19:39:33+00:00

Add PL4 support for ArrowLake-U platform.

Signed-off-by: Sumeet Pawnikar 
Signed-off-by: Zhang Rui 
Reviewed-by: Srinivas Pandruvada 
Link: https://patch.msgid.link/20240930081801.28502-5-rui.zhang@intel.com
Signed-off-by: Rafael J. Wysocki

powercap: intel_rapl_tpmi: Ignore minor version change

2024-10-08T19:38:49+00:00

The hardware definition of every TPMI feature contains a major and minor
version. When there is a change in the MMIO offset or change in the
definition of a field, hardware will change major version. For addition
of new fields without modifying existing MMIO offsets or fields, only
the minor version is changed.

If the driver has not been updated to recognize a new hardware major
version, it cannot provide the RAPL interface to users due to possible
register layout incompatibilities. However, the driver does not need to
be updated every time the hardware minor version changes because in that
case it will just miss some new functionality exposed by the hardware.

The current implementation causes the driver to refuse to work for any
hardware version change which is unnecessarily restrictive.

If there is a minor version mismatch, log an information message and
continue, but if there is a major version mismatch, log a warning and
exit (as before).

Signed-off-by: Zhang Rui 
Reviewed-by: Srinivas Pandruvada 
Link: https://patch.msgid.link/20240930081801.28502-4-rui.zhang@intel.com
Fixes: 9eef7f9da928 ("powercap: intel_rapl: Introduce RAPL TPMI interface driver")
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki

powercap: intel_rapl_tpmi: Fix bogus register reading

2024-10-07T18:10:56+00:00

The TPMI_RAPL_REG_DOMAIN_INFO value needs to be multiplied by 8 to get
the register offset.

Cc: All applicable 
Fixes: 903eb9fb85e3 ("powercap: intel_rapl_tpmi: Fix System Domain probing")
Signed-off-by: Zhang Rui 
Link: https://patch.msgid.link/20240930081801.28502-2-rui.zhang@intel.com
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki

powercap: intel_rapl: Change an error pointer to NULL

2024-08-23T13:45:17+00:00

The rapl_find_package_domain_cpuslocked() function is supposed to
return NULL on error.

This new error patch returns ERR_PTR(-EINVAL) but none of the callers
check for that so it would lead to an Oops.

Fixes: 26096aed255f ("powercap/intel_rapl: Fix the energy-pkg event for AMD CPUs")
Signed-off-by: Dan Carpenter 
Link: https://patch.msgid.link/fa719c6a-8d3b-4cca-9b43-bcd477ff6655@stanley.mountain
Signed-off-by: Rafael J. Wysocki

powercap: intel_rapl: Fix off by one in get_rpi()

2024-08-21T10:59:55+00:00

The rp->priv->rpi array is either rpi_msr or rpi_tpmi which have
NR_RAPL_PRIMITIVES number of elements.  Thus the > needs to be >=
to prevent an off by one access.

Fixes: 98ff639a7289 ("powercap: intel_rapl: Support per Interface primitive information")
Signed-off-by: Dan Carpenter 
Acked-by: Zhang Rui 
Link: https://patch.msgid.link/86e3a059-504d-4795-a5ea-4a653f3b41f8@stanley.mountain
Signed-off-by: Rafael J. Wysocki