From: Zhao Yakui <yakui.zhao@xxxxxxxxx> The IRQ operation(enable/disable) should be avoided when throttling is controlled via PTC method. It is replaced by the migration of task. This fixes an oops on T61 -- a regression due to f79f06ab9f86 b/c FixedHW support tried to read remote MSR with interrupts disabled. Signed-off-by: Zhao Yakui <yakui.zhao@xxxxxxxxx> Signed-off-by: Len Brown <len.brown@xxxxxxxxx> --- drivers/acpi/processor_throttling.c | 36 +++++++++++++++++++++++++++------- 1 files changed, 28 insertions(+), 8 deletions(-) diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c index c26c61f..6742d7b 100644 --- a/drivers/acpi/processor_throttling.c +++ b/drivers/acpi/processor_throttling.c @@ -29,6 +29,7 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> +#include <linux/sched.h> #include <linux/cpufreq.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> @@ -413,7 +414,7 @@ static int acpi_throttling_rdmsr(struct acpi_processor *pr, } else { msr_low = 0; msr_high = 0; - rdmsr_on_cpu(cpu, MSR_IA32_THERM_CONTROL, + rdmsr_safe(MSR_IA32_THERM_CONTROL, (u32 *)&msr_low , (u32 *) &msr_high); msr = (msr_high << 32) | msr_low; *value = (acpi_integer) msr; @@ -438,7 +439,7 @@ static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value) "HARDWARE addr space,NOT supported yet\n"); } else { msr = value; - wrmsr_on_cpu(cpu, MSR_IA32_THERM_CONTROL, + wrmsr_safe(MSR_IA32_THERM_CONTROL, msr & 0xffffffff, msr >> 32); ret = 0; } @@ -572,21 +573,32 @@ static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr) return -ENODEV; pr->throttling.state = 0; - local_irq_disable(); + value = 0; ret = acpi_read_throttling_status(pr, &value); if (ret >= 0) { state = acpi_get_throttling_state(pr, value); pr->throttling.state = state; } - local_irq_enable(); return 0; } static int acpi_processor_get_throttling(struct acpi_processor *pr) { - return pr->throttling.acpi_processor_get_throttling(pr); + cpumask_t saved_mask; + int ret; + + /* + * Migrate task to the cpu pointed by pr. + */ + saved_mask = current->cpus_allowed; + set_cpus_allowed(current, cpumask_of_cpu(pr->id)); + ret = pr->throttling.acpi_processor_get_throttling(pr); + /* restore the previous state */ + set_cpus_allowed(current, saved_mask); + + return ret; } static int acpi_processor_get_fadt_info(struct acpi_processor *pr) @@ -717,21 +729,29 @@ static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr, if (state < pr->throttling_platform_limit) return -EPERM; - local_irq_disable(); value = 0; ret = acpi_get_throttling_value(pr, state, &value); if (ret >= 0) { acpi_write_throttling_state(pr, value); pr->throttling.state = state; } - local_irq_enable(); return 0; } int acpi_processor_set_throttling(struct acpi_processor *pr, int state) { - return pr->throttling.acpi_processor_set_throttling(pr, state); + cpumask_t saved_mask; + int ret; + /* + * Migrate task to the cpu pointed by pr. + */ + saved_mask = current->cpus_allowed; + set_cpus_allowed(current, cpumask_of_cpu(pr->id)); + ret = pr->throttling.acpi_processor_set_throttling(pr, state); + /* restore the previous state */ + set_cpus_allowed(current, saved_mask); + return ret; } int acpi_processor_get_throttling_info(struct acpi_processor *pr) -- 1.5.3.7.949.g2221a6 - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html