From dbf8243fe3682941df2af0019ba72f96b1d80dd5 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sat, 11 Sep 2021 12:12:16 +0800 Subject: [PATCH] Intel: intel_idle: Add module parameter to prevent ACPI _CST from being used mainline inclusion from mainline-v5.6-rc1 commit 4ec32d9e8e5b6d6eb491eeee3938665d8a2388fa category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I47H3V CVE: NA -------------------------------- commit 4ec32d9e8e5b6d6eb491eeee3938665d8a2388fa upstream Add a new module parameter called "no_acpi" to the intel_idle driver to allow the driver to be prevented from using ACPI _CST via kernel command line. Signed-off-by: Rafael J. Wysocki Signed-off-by: yjia Signed-off-by: Jackie Liu Signed-off-by: Zheng Zengkai Reviewed-by: Hanjun Guo Reviewed-by: Xie XiuQi Signed-off-by: Yang Yingliang --- drivers/idle/intel_idle.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index 487edbad098d..cfd3ecafed7b 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -1152,6 +1152,10 @@ static bool intel_idle_max_cstate_reached(int cstate) #ifdef CONFIG_ACPI_PROCESSOR_CSTATE #include +static bool no_acpi __read_mostly; +module_param(no_acpi, bool, 0444); +MODULE_PARM_DESC(no_acpi, "Do not use ACPI _CST for building the idle states list"); + static struct acpi_processor_power acpi_state_table; /** @@ -1181,6 +1185,11 @@ static bool intel_idle_acpi_cst_extract(void) { unsigned int cpu; + if (no_acpi) { + pr_debug("Not allowed to use ACPI _CST\n"); + return false; + } + for_each_possible_cpu(cpu) { struct acpi_processor *pr = per_cpu(processors, cpu); -- GitLab