linux-stable.git/drivers/cpufreq, branch v5.4.294 Linux kernel stable tree cpufreq: scpi: Fix null-ptr-deref in scpi_cpufreq_get_rate() 2025-05-02T05:39:25+00:00 Henry Martin bsdhenrymartin@gmail.com 2025-04-08T15:03:54+00:00 ad4796f2da495b2cbbd0fccccbcbf63f2aeee613 [ Upstream commit 73b24dc731731edf762f9454552cb3a5b7224949 ] cpufreq_cpu_get_raw() can return NULL when the target CPU is not present in the policy->cpus mask. scpi_cpufreq_get_rate() does not check for this case, which results in a NULL pointer dereference. Fixes: 343a8d17fa8d ("cpufreq: scpi: remove arm_big_little dependency") Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 73b24dc731731edf762f9454552cb3a5b7224949 ]

cpufreq_cpu_get_raw() can return NULL when the target CPU is not present
in the policy->cpus mask. scpi_cpufreq_get_rate() does not check for
this case, which results in a NULL pointer dereference.

Fixes: 343a8d17fa8d ("cpufreq: scpi: remove arm_big_little dependency")
Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
cpufreq: Reference count policy in cpufreq_update_limits() 2025-05-02T05:39:21+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2025-03-28T20:39:08+00:00 66e30ca3c60c26c32b71ed250a5fc59c9c778242 commit 9e4e249018d208678888bdf22f6b652728106528 upstream. Since acpi_processor_notify() can be called before registering a cpufreq driver or even in cases when a cpufreq driver is not registered at all, cpufreq_update_limits() needs to check if a cpufreq driver is present and prevent it from being unregistered. For this purpose, make it call cpufreq_cpu_get() to obtain a cpufreq policy pointer for the given CPU and reference count the corresponding policy object, if present. Fixes: 5a25e3f7cc53 ("cpufreq: intel_pstate: Driver-specific handling of _PPC updates") Closes: https://lore.kernel.org/linux-acpi/Z-ShAR59cTow0KcR@mail-itl Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> Cc: All applicable <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Link: https://patch.msgid.link/1928789.tdWV9SEqCh@rjwysocki.net [do not use __free(cpufreq_cpu_put) in a backport] Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 9e4e249018d208678888bdf22f6b652728106528 upstream.

Since acpi_processor_notify() can be called before registering a cpufreq
driver or even in cases when a cpufreq driver is not registered at all,
cpufreq_update_limits() needs to check if a cpufreq driver is present
and prevent it from being unregistered.

For this purpose, make it call cpufreq_cpu_get() to obtain a cpufreq
policy pointer for the given CPU and reference count the corresponding
policy object, if present.

Fixes: 5a25e3f7cc53 ("cpufreq: intel_pstate: Driver-specific handling of _PPC updates")
Closes: https://lore.kernel.org/linux-acpi/Z-ShAR59cTow0KcR@mail-itl
Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://patch.msgid.link/1928789.tdWV9SEqCh@rjwysocki.net
[do not use __free(cpufreq_cpu_put) in a backport]
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cpufreq: governor: Fix negative 'idle_time' handling in dbs_update() 2025-04-10T12:29:39+00:00 Jie Zhan zhanjie9@hisilicon.com 2025-02-13T03:55:10+00:00 73cee9b56a3d32f72390aafd0e55b5e1320060d8 [ Upstream commit 3698dd6b139dc37b35a9ad83d9330c1f99666c02 ] We observed an issue that the CPU frequency can't raise up with a 100% CPU load when NOHZ is off and the 'conservative' governor is selected. 'idle_time' can be negative if it's obtained from get_cpu_idle_time_jiffy() when NOHZ is off. This was found and explained in commit 9485e4ca0b48 ("cpufreq: governor: Fix handling of special cases in dbs_update()"). However, commit 7592019634f8 ("cpufreq: governors: Fix long idle detection logic in load calculation") introduced a comparison between 'idle_time' and 'samling_rate' to detect a long idle interval. While 'idle_time' is converted to int before comparison, it's actually promoted to unsigned again when compared with an unsigned 'sampling_rate'. Hence, this leads to wrong idle interval detection when it's in fact 100% busy and sets policy_dbs->idle_periods to a very large value. 'conservative' adjusts the frequency to minimum because of the large 'idle_periods', such that the frequency can't raise up. 'Ondemand' doesn't use policy_dbs->idle_periods so it fortunately avoids the issue. Correct negative 'idle_time' to 0 before any use of it in dbs_update(). Fixes: 7592019634f8 ("cpufreq: governors: Fix long idle detection logic in load calculation") Signed-off-by: Jie Zhan <zhanjie9@hisilicon.com> Reviewed-by: Chen Yu <yu.c.chen@intel.com> Link: https://patch.msgid.link/20250213035510.2402076-1-zhanjie9@hisilicon.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 3698dd6b139dc37b35a9ad83d9330c1f99666c02 ]

We observed an issue that the CPU frequency can't raise up with a 100% CPU
load when NOHZ is off and the 'conservative' governor is selected.

'idle_time' can be negative if it's obtained from get_cpu_idle_time_jiffy()
when NOHZ is off.  This was found and explained in commit 9485e4ca0b48
("cpufreq: governor: Fix handling of special cases in dbs_update()").

However, commit 7592019634f8 ("cpufreq: governors: Fix long idle detection
logic in load calculation") introduced a comparison between 'idle_time' and
'samling_rate' to detect a long idle interval.  While 'idle_time' is
converted to int before comparison, it's actually promoted to unsigned
again when compared with an unsigned 'sampling_rate'.  Hence, this leads to
wrong idle interval detection when it's in fact 100% busy and sets
policy_dbs->idle_periods to a very large value.  'conservative' adjusts the
frequency to minimum because of the large 'idle_periods', such that the
frequency can't raise up.  'Ondemand' doesn't use policy_dbs->idle_periods
so it fortunately avoids the issue.

Correct negative 'idle_time' to 0 before any use of it in dbs_update().

Fixes: 7592019634f8 ("cpufreq: governors: Fix long idle detection logic in load calculation")
Signed-off-by: Jie Zhan <zhanjie9@hisilicon.com>
Reviewed-by: Chen Yu <yu.c.chen@intel.com>
Link: https://patch.msgid.link/20250213035510.2402076-1-zhanjie9@hisilicon.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
cpufreq: s3c64xx: Fix compilation warning 2025-03-13T11:43:06+00:00 Viresh Kumar viresh.kumar@linaro.org 2025-01-22T06:06:16+00:00 619708ef44f31cd3a08f774b4897179244c68448 commit 43855ac61483cb914f060851535ea753c094b3e0 upstream. The driver generates following warning when regulator support isn't enabled in the kernel. Fix it. drivers/cpufreq/s3c64xx-cpufreq.c: In function 's3c64xx_cpufreq_set_target': >> drivers/cpufreq/s3c64xx-cpufreq.c:55:22: warning: variable 'old_freq' set but not used [-Wunused-but-set-variable] 55 | unsigned int old_freq, new_freq; | ^~~~~~~~ >> drivers/cpufreq/s3c64xx-cpufreq.c:54:30: warning: variable 'dvfs' set but not used [-Wunused-but-set-variable] 54 | struct s3c64xx_dvfs *dvfs; | ^~~~ Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202501191803.CtfT7b2o-lkp@intel.com/ Cc: 5.4+ <stable@vger.kernel.org> # v5.4+ Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Link: https://patch.msgid.link/236b227e929e5adc04d1e9e7af6845a46c8e9432.1737525916.git.viresh.kumar@linaro.org Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 43855ac61483cb914f060851535ea753c094b3e0 upstream.

The driver generates following warning when regulator support isn't
enabled in the kernel. Fix it.

   drivers/cpufreq/s3c64xx-cpufreq.c: In function 's3c64xx_cpufreq_set_target':
>> drivers/cpufreq/s3c64xx-cpufreq.c:55:22: warning: variable 'old_freq' set but not used [-Wunused-but-set-variable]
      55 |         unsigned int old_freq, new_freq;
         |                      ^~~~~~~~
>> drivers/cpufreq/s3c64xx-cpufreq.c:54:30: warning: variable 'dvfs' set but not used [-Wunused-but-set-variable]
      54 |         struct s3c64xx_dvfs *dvfs;
         |                              ^~~~

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202501191803.CtfT7b2o-lkp@intel.com/
Cc: 5.4+ <stable@vger.kernel.org> # v5.4+
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://patch.msgid.link/236b227e929e5adc04d1e9e7af6845a46c8e9432.1737525916.git.viresh.kumar@linaro.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cpufreq: loongson2: Unregister platform_driver on failure 2024-12-14T18:44:29+00:00 Yuan Can yuancan@huawei.com 2024-10-16T09:06:15+00:00 b3617ac6aa9a809e6255f8e2fec7783465d13ca3 [ Upstream commit 5f856d71ccdf89b4bac0ff70ebb0bb582e7f7f18 ] When cpufreq_register_driver() returns error, the cpufreq_init() returns without unregister platform_driver, fix by add missing platform_driver_unregister() when cpufreq_register_driver() failed. Fixes: f8ede0f700f5 ("MIPS: Loongson 2F: Add CPU frequency scaling support") Signed-off-by: Yuan Can <yuancan@huawei.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 5f856d71ccdf89b4bac0ff70ebb0bb582e7f7f18 ]

When cpufreq_register_driver() returns error, the cpufreq_init() returns
without unregister platform_driver, fix by add missing
platform_driver_unregister() when cpufreq_register_driver() failed.

Fixes: f8ede0f700f5 ("MIPS: Loongson 2F: Add CPU frequency scaling support")
Signed-off-by: Yuan Can <yuancan@huawei.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
cpufreq: exit() callback is optional 2024-06-16T11:28:34+00:00 Viresh Kumar viresh.kumar@linaro.org 2024-04-12T05:49:20+00:00 2d730b465e377396d2a09a53524b96b111f7ccb6 [ Upstream commit b8f85833c05730d631576008daaa34096bc7f3ce ] The exit() callback is optional and shouldn't be called without checking a valid pointer first. Also, we must clear freq_table pointer even if the exit() callback isn't present. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Fixes: 91a12e91dc39 ("cpufreq: Allow light-weight tear down and bring up of CPUs") Fixes: f339f3541701 ("cpufreq: Rearrange locking in cpufreq_remove_dev()") Reported-by: Lizhe <sensor1010@163.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit b8f85833c05730d631576008daaa34096bc7f3ce ]

The exit() callback is optional and shouldn't be called without checking
a valid pointer first.

Also, we must clear freq_table pointer even if the exit() callback isn't
present.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Fixes: 91a12e91dc39 ("cpufreq: Allow light-weight tear down and bring up of CPUs")
Fixes: f339f3541701 ("cpufreq: Rearrange locking in cpufreq_remove_dev()")
Reported-by: Lizhe <sensor1010@163.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
cpufreq: Rearrange locking in cpufreq_remove_dev() 2024-06-16T11:28:34+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2022-05-11T15:51:39+00:00 e660a2e670dc5c6e33e5607472d09000bc975714 [ Upstream commit f339f3541701d824a0256ad4bf14c26ceb6d79c3 ] Currently, cpufreq_remove_dev() invokes the ->exit() driver callback without holding the policy rwsem which is inconsistent with what happens if ->exit() is invoked directly from cpufreq_offline(). It also manipulates the real_cpus mask and removes the CPU device symlink without holding the policy rwsem, but cpufreq_offline() holds the rwsem around the modifications thereof. For consistency, modify cpufreq_remove_dev() to hold the policy rwsem until the ->exit() callback has been called (or it has been determined that it is not necessary to call it). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Stable-dep-of: b8f85833c057 ("cpufreq: exit() callback is optional") Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit f339f3541701d824a0256ad4bf14c26ceb6d79c3 ]

Currently, cpufreq_remove_dev() invokes the ->exit() driver callback
without holding the policy rwsem which is inconsistent with what
happens if ->exit() is invoked directly from cpufreq_offline().

It also manipulates the real_cpus mask and removes the CPU device
symlink without holding the policy rwsem, but cpufreq_offline() holds
the rwsem around the modifications thereof.

For consistency, modify cpufreq_remove_dev() to hold the policy rwsem
until the ->exit() callback has been called (or it has been determined
that it is not necessary to call it).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Stable-dep-of: b8f85833c057 ("cpufreq: exit() callback is optional")
Signed-off-by: Sasha Levin <sashal@kernel.org>
cpufreq: Split cpufreq_offline() 2024-06-16T11:28:34+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2022-05-11T15:50:09+00:00 14bef1ad614e59c99c35b981cb72dfc439fa7f93 [ Upstream commit fddd8f86dff4a24742a7f0322ccbb34c6c1c9850 ] Split the "core" part running under the policy rwsem out of cpufreq_offline() to allow the locking in cpufreq_remove_dev() to be rearranged more easily. As a side-effect this eliminates the unlock label that's not needed any more. No expected functional impact. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Stable-dep-of: b8f85833c057 ("cpufreq: exit() callback is optional") Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit fddd8f86dff4a24742a7f0322ccbb34c6c1c9850 ]

Split the "core" part running under the policy rwsem out of
cpufreq_offline() to allow the locking in cpufreq_remove_dev() to be
rearranged more easily.

As a side-effect this eliminates the unlock label that's not needed
any more.

No expected functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Stable-dep-of: b8f85833c057 ("cpufreq: exit() callback is optional")
Signed-off-by: Sasha Levin <sashal@kernel.org>
cpufreq: Reorganize checks in cpufreq_offline() 2024-06-16T11:28:34+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2022-05-11T15:48:41+00:00 458965e83c7523f95b2bd3ce3dd132946d8d6461 [ Upstream commit e1e962c5b9edbc628a335bcdbd010331a12d3e5b ] Notice that cpufreq_offline() only needs to check policy_is_inactive() once and rearrange the code in there to make that happen. No expected functional impact. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Stable-dep-of: b8f85833c057 ("cpufreq: exit() callback is optional") Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit e1e962c5b9edbc628a335bcdbd010331a12d3e5b ]

Notice that cpufreq_offline() only needs to check policy_is_inactive()
once and rearrange the code in there to make that happen.

No expected functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Stable-dep-of: b8f85833c057 ("cpufreq: exit() callback is optional")
Signed-off-by: Sasha Levin <sashal@kernel.org>
cpufreq: imx6q: Don't disable 792 Mhz OPP unnecessarily 2023-12-08T07:44:28+00:00 Christoph Niedermaier cniedermaier@dh-electronics.com 2023-11-22T13:41:13+00:00 1a051c6d15aaa1178be77dce7ba56dc570c01dab [ Upstream commit 2e4e0984c7d696cc74cf2fd7e7f62997f0e9ebe6 ] For a 900MHz i.MX6ULL CPU the 792MHz OPP is disabled. There is no convincing reason to disable this OPP. If a CPU can run at 900MHz, it should also be able to cope with 792MHz. Looking at the voltage level of 792MHz in [1] (page 24, table 10. "Operating Ranges") the current defined OPP is above the minimum. So the voltage level shouldn't be a problem. However in [2] (page 24, table 10. "Operating Ranges"), it is not mentioned that 792MHz OPP isn't allowed. Change it to only disable 792MHz OPP for i.MX6ULL types below 792 MHz. [1] https://www.nxp.com/docs/en/data-sheet/IMX6ULLIEC.pdf [2] https://www.nxp.com/docs/en/data-sheet/IMX6ULLCEC.pdf Fixes: 0aa9abd4c212 ("cpufreq: imx6q: check speed grades for i.MX6ULL") Signed-off-by: Christoph Niedermaier <cniedermaier@dh-electronics.com> Reviewed-by: Marek Vasut <marex@denx.de> Reviewed-by: Fabio Estevam <festevam@denx.de> [ Viresh: Edited subject ] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 2e4e0984c7d696cc74cf2fd7e7f62997f0e9ebe6 ]

For a 900MHz i.MX6ULL CPU the 792MHz OPP is disabled. There is no
convincing reason to disable this OPP. If a CPU can run at 900MHz,
it should also be able to cope with 792MHz. Looking at the voltage
level of 792MHz in [1] (page 24, table 10. "Operating Ranges") the
current defined OPP is above the minimum. So the voltage level
shouldn't be a problem. However in [2] (page 24, table 10.
"Operating Ranges"), it is not mentioned that 792MHz OPP isn't
allowed. Change it to only disable 792MHz OPP for i.MX6ULL types
below 792 MHz.

[1] https://www.nxp.com/docs/en/data-sheet/IMX6ULLIEC.pdf
[2] https://www.nxp.com/docs/en/data-sheet/IMX6ULLCEC.pdf

Fixes: 0aa9abd4c212 ("cpufreq: imx6q: check speed grades for i.MX6ULL")
Signed-off-by: Christoph Niedermaier <cniedermaier@dh-electronics.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Reviewed-by: Fabio Estevam <festevam@denx.de>
[ Viresh: Edited subject ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>