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authorJoseph Cihula <joseph.cihula@intel.com>2009-06-30 19:31:07 -0700
committerH. Peter Anvin <hpa@zytor.com>2009-07-21 11:50:04 -0700
commit86886e55b273f565935491816c7c96b82469d4f8 (patch)
tree0045d68e4720f545f546e216c71104ab31d9d80c /kernel/cpu.c
parent840c2baf2d4cdf35ecc3b7fcbba7740f97de30a4 (diff)
downloadlinux-2.6.34-ux500-86886e55b273f565935491816c7c96b82469d4f8.tar.gz
x86, intel_txt: Intel TXT Sx shutdown support
Support for graceful handling of sleep states (S3/S4/S5) after an Intel(R) TXT launch. Without this patch, attempting to place the system in one of the ACPI sleep states (S3/S4/S5) will cause the TXT hardware to treat this as an attack and will cause a system reset, with memory locked. Not only may the subsequent memory scrub take some time, but the platform will be unable to enter the requested power state. This patch calls back into the tboot so that it may properly and securely clean up system state and clear the secrets-in-memory flag, after which it will place the system into the requested sleep state using ACPI information passed by the kernel. arch/x86/kernel/smpboot.c | 2 ++ drivers/acpi/acpica/hwsleep.c | 3 +++ kernel/cpu.c | 7 ++++++- 3 files changed, 11 insertions(+), 1 deletion(-) Signed-off-by: Joseph Cihula <joseph.cihula@intel.com> Signed-off-by: Shane Wang <shane.wang@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Diffstat (limited to 'kernel/cpu.c')
-rw-r--r--kernel/cpu.c7
1 files changed, 6 insertions, 1 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 8ce10043e4a..ff071e022a8 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -14,6 +14,7 @@
#include <linux/kthread.h>
#include <linux/stop_machine.h>
#include <linux/mutex.h>
+#include <asm/tboot.h>
#ifdef CONFIG_SMP
/* Serializes the updates to cpu_online_mask, cpu_present_mask */
@@ -376,7 +377,7 @@ static cpumask_var_t frozen_cpus;
int disable_nonboot_cpus(void)
{
- int cpu, first_cpu, error;
+ int cpu, first_cpu, error, num_cpus = 0;
error = stop_machine_create();
if (error)
@@ -391,6 +392,7 @@ int disable_nonboot_cpus(void)
for_each_online_cpu(cpu) {
if (cpu == first_cpu)
continue;
+ num_cpus++;
error = _cpu_down(cpu, 1);
if (!error) {
cpumask_set_cpu(cpu, frozen_cpus);
@@ -401,6 +403,9 @@ int disable_nonboot_cpus(void)
break;
}
}
+ /* ensure all CPUs have gone into wait-for-SIPI */
+ error |= tboot_wait_for_aps(num_cpus);
+
if (!error) {
BUG_ON(num_online_cpus() > 1);
/* Make sure the CPUs won't be enabled by someone else */