]> www.infradead.org Git - users/jedix/linux-maple.git/commit
cpufreq: ACPI: Re-sync CPU boost state on system resume
authorViresh Kumar <viresh.kumar@linaro.org>
Thu, 24 Apr 2025 16:20:14 +0000 (21:50 +0530)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Fri, 25 Apr 2025 16:22:46 +0000 (18:22 +0200)
commit3d59224947b024c9b2aa6e149a1537d449adb828
treed668dc85fd2a7f44d8ce378361cfa034c8f1aaa4
parent5786ef8ad8d4222fdc2e7cf65337880695cef60e
cpufreq: ACPI: Re-sync CPU boost state on system resume

During CPU hotunplug events (such as those occurring during
suspend/resume cycles), platform firmware may modify the CPU boost
state.

If boost was disabled prior to CPU removal, it correctly remains
disabled upon re-plug. However, if firmware re-enables boost while the
CPU is offline, the CPU may return with boost enabled—even if it was
originally disabled—once it is hotplugged back in. This leads to
inconsistent behavior and violates user or kernel policy expectations.

To maintain consistency, ensure the boost state is re-synchronized with
the kernel policy when a CPU is hotplugged back in.

Note: This re-synchronization is not necessary during the initial call
to ->init() for a CPU, as the cpufreq core handles it via
cpufreq_online(). At that point, acpi_cpufreq_driver.boost_enabled is
initialized to the value returned by boost_state(0).

Fixes: 2b16c631832d ("cpufreq: ACPI: Remove set_boost in acpi_cpufreq_cpu_init()")
Reported-by: Nicholas Chin <nic.c3.14@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220013
Tested-by: Nicholas Chin <nic.c3.14@gmail.com>
Reviewed-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://patch.msgid.link/9c7de55fb06015c1b77e7dafd564b659838864e0.1745511526.git.viresh.kumar@linaro.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
drivers/cpufreq/acpi-cpufreq.c