mainline inclusion from mainline-v6.15-rc4 commit 3d59224947b024c9b2aa6e149a1537d449adb828 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/ICZ7F3 CVE: NA Reference: https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commi... ---------------------------------------------------------------------- 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... Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Lifeng Zheng <zhenglifeng1@huawei.com> Signed-off-by: Hongye Lin <linhongye@h-partners.com> --- drivers/cpufreq/acpi-cpufreq.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c index 221e3c1e2e75..1a52f561e324 100644 --- a/drivers/cpufreq/acpi-cpufreq.c +++ b/drivers/cpufreq/acpi-cpufreq.c @@ -953,6 +953,13 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) if (perf->states[0].core_frequency * 1000 != freq_table[0].frequency) pr_warn(FW_WARN "P-state 0 is not max freq\n"); + /* + * The firmware may have altered boost state while the CPU was offline + * (for example during a suspend-resume cycle). + */ + if (acpi_cpufreq_driver.set_boost && policy->boost_enabled != boost_state(cpu)) + set_boost(policy, policy->boost_enabled); + return result; err_unreg: -- 2.33.0