kernel/linux.git/drivers/cpufreq, branch v5.15.7

cpufreq: Fix get_cpu_device() failure in add_cpu_dev_symlink()

2021-12-08T08:04:42+00:00

commit 2c1b5a84669d2477d8fffe9136e86a2cff591729 upstream. When I hot added a CPU, I found 'cpufreq' directory was not created below /sys/devices/system/cpu/cpuX/. It is because get_cpu_device() failed in add_cpu_dev_symlink(). cpufreq_add_dev() is the .add_dev callback of a CPU subsys interface. It will be called when the CPU device registered into the system. The call chain is as follows: register_cpu() ->device_register() ->device_add() ->bus_probe_device() ->cpufreq_add_dev() But only after the CPU device has been registered, we can get the CPU device by get_cpu_device(), otherwise it will return NULL. Since we already have the CPU device in cpufreq_add_dev(), pass it to add_cpu_dev_symlink(). I noticed that the 'kobj' of the CPU device has been added into the system before cpufreq_add_dev(). Fixes: 2f0ba790df51 ("cpufreq: Fix creation of symbolic links to policy directories") Signed-off-by: Xiongfeng Wang Acked-by: Viresh Kumar Cc: All applicable Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

cpufreq: intel_pstate: Add Ice Lake server to out-of-band IDs

2021-12-01T08:04:51+00:00

[ Upstream commit cd23f02f166892603eb9f2d488152b975872b682 ] Commit fbdc21e9b038 ("cpufreq: intel_pstate: Add Icelake servers support in no-HWP mode") enabled the use of Intel P-State driver for Ice Lake servers. But it doesn't cover the case when OS can't control P-States. Therefore, for Ice Lake server, if MSR_MISC_PWR_MGMT bits 8 or 18 are enabled, then the Intel P-State driver should exit as OS can't control P-States. Fixes: fbdc21e9b038 ("cpufreq: intel_pstate: Add Icelake servers support in no-HWP mode") Signed-off-by: Adamos Ttofari Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

cpufreq: intel_pstate: Fix active mode offline/online EPP handling

2021-12-01T08:04:44+00:00

commit ed38eb49d101e829ae0f8c0a0d3bf5cb6bcbc6b2 upstream. After commit 4adcf2e5829f ("cpufreq: intel_pstate: Add ->offline and ->online callbacks") the EPP value set by the "performance" scaling algorithm in the active mode is not restored after an offline/online cycle which replaces it with the saved EPP value coming from user space. Address this issue by forcing intel_pstate_hwp_set() to set a new EPP value when it runs first time after online. Fixes: 4adcf2e5829f ("cpufreq: intel_pstate: Add ->offline and ->online callbacks") Link: https://lore.kernel.org/linux-pm/adc7132c8655bd4d1c8b6129578e931a14fe1db2.camel@linux.intel.com/ Reported-by: Srinivas Pandruvada Cc: 5.9+ # 5.9+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

cpufreq: intel_pstate: Clear HWP desired on suspend/shutdown and offline

2021-11-18T18:17:08+00:00

[ Upstream commit dbea75fe18f60e364de6d994fc938a24ba249d81 ] Commit a365ab6b9dfb ("cpufreq: intel_pstate: Implement the ->adjust_perf() callback") caused intel_pstate to use nonzero HWP desired values in certain usage scenarios, but it did not prevent them from being leaked into the confugirations in which HWP desired is expected to be 0. The failing scenarios are switching the driver from the passive mode to the active mode and starting a new kernel via kexec() while intel_pstate is running in the passive mode. To address this issue, ensure that HWP desired will be cleared on offline and suspend/shutdown. Fixes: a365ab6b9dfb ("cpufreq: intel_pstate: Implement the ->adjust_perf() callback") Reported-by: Julia Lawall Tested-by: Julia Lawall Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

cpufreq: intel_pstate: Fix cpu->pstate.turbo_freq initialization

2021-11-18T18:16:42+00:00

[ Upstream commit c72bcf0ab87a92634e58af62e89af0f40dfd0b88 ] Fix a problem in active mode that cpu->pstate.turbo_freq is initialized only if HWP-to-frequency scaling factor is refined. In passive mode, this problem is not exposed, because cpu->pstate.turbo_freq is set again, later in intel_cpufreq_cpu_init()->intel_pstate_get_hwp_cap(). Fixes: eb3693f0521e ("cpufreq: intel_pstate: hybrid: CPU-specific scaling factor") Signed-off-by: Zhang Rui Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

cpufreq: Make policy min/max hard requirements

2021-11-18T18:16:14+00:00

[ Upstream commit 15171769069408789a72f9aa9a52cc931b839b56 ] When applying the policy min/max limits, the requested frequency is simply clamped to not be out of range. It means, however, if one of the boundaries isn't an available frequency, the frequency resolution can return a value out of those limits, depending on the relation used. e.g. freq{0,1,2} being available frequencies. freq0 policy->min freq1 policy->max freq2 | | | | | 17kHz 18kHz 19kHz 20kHz 21kHz __resolve_freq(21kHz, CPUFREQ_RELATION_L) -> 21kHz (out of bounds) __resolve_freq(17kHz, CPUFREQ_RELATION_H) -> 17kHz (out of bounds) If, during the policy init, we resolve the requested min/max to existing frequencies, we ensure that any CPUFREQ_RELATION_* would resolve to a frequency which is inside the policy min/max range. Making the policy limits rigid helps to introduce the inefficient frequencies support. Resolving an inefficient frequency to an efficient one should not transgress policy->max (which can be set for thermal reason) and having a value we can trust simplify this comparison. Signed-off-by: Vincent Donnefort Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

Merge tag 'pm-5.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2021-09-17T19:05:04+00:00

Pull power management fixes from Rafael Wysocki: "These fix two cpufreq issues, one in the intel_pstate driver and one in the core. Specifics: - Prevent intel_pstate from avoiding to use HWP, even if instructed to do so via the kernel command line, when HWP has been enabled already by the platform firmware (Doug Smythies). - Prevent use-after-free from occurring in the schedutil cpufreq governor on exit by fixing a core helper function that attempts to access memory associated with a kobject after calling kobject_put() on it (James Morse)" * tag 'pm-5.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpufreq: schedutil: Destroy mutex before kobject_put() frees the memory cpufreq: intel_pstate: Override parameters if HWP forced by BIOS

cpufreq: vexpress: Drop unused variable

2021-09-16T18:29:27+00:00

arm:allmodconfig fails to build with the following error. drivers/cpufreq/vexpress-spc-cpufreq.c:454:13: error: unused variable 'cur_cluster' Remove the unused variable. Fixes: bb8c26d9387f ("cpufreq: vexpress: Set CPUFREQ_IS_COOLING_DEV flag") Cc: Viresh Kumar Signed-off-by: Guenter Roeck Reviewed-by: Kees Cook Signed-off-by: Linus Torvalds

cpufreq: schedutil: Destroy mutex before kobject_put() frees the memory

2021-09-14T17:01:36+00:00

Since commit e5c6b312ce3c ("cpufreq: schedutil: Use kobject release() method to free sugov_tunables") kobject_put() has kfree()d the attr_set before gov_attr_set_put() returns. kobject_put() isn't the last user of attr_set in gov_attr_set_put(), the subsequent mutex_destroy() triggers a use-after-free: | BUG: KASAN: use-after-free in mutex_is_locked+0x20/0x60 | Read of size 8 at addr ffff000800ca4250 by task cpuhp/2/20 | | CPU: 2 PID: 20 Comm: cpuhp/2 Not tainted 5.15.0-rc1 #12369 | Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development | Platform, BIOS EDK II Jul 30 2018 | Call trace: | dump_backtrace+0x0/0x380 | show_stack+0x1c/0x30 | dump_stack_lvl+0x8c/0xb8 | print_address_description.constprop.0+0x74/0x2b8 | kasan_report+0x1f4/0x210 | kasan_check_range+0xfc/0x1a4 | __kasan_check_read+0x38/0x60 | mutex_is_locked+0x20/0x60 | mutex_destroy+0x80/0x100 | gov_attr_set_put+0xfc/0x150 | sugov_exit+0x78/0x190 | cpufreq_offline.isra.0+0x2c0/0x660 | cpuhp_cpufreq_offline+0x14/0x24 | cpuhp_invoke_callback+0x430/0x6d0 | cpuhp_thread_fun+0x1b0/0x624 | smpboot_thread_fn+0x5e0/0xa6c | kthread+0x3a0/0x450 | ret_from_fork+0x10/0x20 Swap the order of the calls. Fixes: e5c6b312ce3c ("cpufreq: schedutil: Use kobject release() method to free sugov_tunables") Cc: 4.7+ # 4.7+ Signed-off-by: James Morse Signed-off-by: Rafael J. Wysocki

cpufreq: intel_pstate: Override parameters if HWP forced by BIOS

2021-09-13T17:26:08+00:00

If HWP has been already been enabled by BIOS, it may be necessary to override some kernel command line parameters. Once it has been enabled it requires a reset to be disabled. Suggested-by: Rafael J. Wysocki Signed-off-by: Doug Smythies Signed-off-by: Rafael J. Wysocki