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authorOtavio Salvador <otavio@ossystems.com.br>2019-07-15 11:15:02 -0300
committerGitHub <noreply@github.com>2019-07-15 11:15:02 -0300
commit6b774eec1f9d3064e9b33634dfa99d5666d0a73a (patch)
tree64fa879c312d6a52f90e6dbf3f7be2d66de3ddd4 /arch/x86/power/hibernate_64.c
parent774f42075a4800fe4106dffca804e3207bc3c2e7 (diff)
parent286d8c46ed06d5fc1b8c212356a11a19b2c94bc4 (diff)
Merge pull request #50 from MaxKrummenacher/4.14-2.0.x-imx
4.14 2.0.x imx
Diffstat (limited to 'arch/x86/power/hibernate_64.c')
-rw-r--r--arch/x86/power/hibernate_64.c33
1 files changed, 33 insertions, 0 deletions
diff --git a/arch/x86/power/hibernate_64.c b/arch/x86/power/hibernate_64.c
index 0ef5e5204968..9c80966c80ba 100644
--- a/arch/x86/power/hibernate_64.c
+++ b/arch/x86/power/hibernate_64.c
@@ -13,6 +13,7 @@
#include <linux/suspend.h>
#include <linux/scatterlist.h>
#include <linux/kdebug.h>
+#include <linux/cpu.h>
#include <crypto/hash.h>
@@ -347,3 +348,35 @@ int arch_hibernation_header_restore(void *addr)
return 0;
}
+
+int arch_resume_nosmt(void)
+{
+ int ret = 0;
+ /*
+ * We reached this while coming out of hibernation. This means
+ * that SMT siblings are sleeping in hlt, as mwait is not safe
+ * against control transition during resume (see comment in
+ * hibernate_resume_nonboot_cpu_disable()).
+ *
+ * If the resumed kernel has SMT disabled, we have to take all the
+ * SMT siblings out of hlt, and offline them again so that they
+ * end up in mwait proper.
+ *
+ * Called with hotplug disabled.
+ */
+ cpu_hotplug_enable();
+ if (cpu_smt_control == CPU_SMT_DISABLED ||
+ cpu_smt_control == CPU_SMT_FORCE_DISABLED) {
+ enum cpuhp_smt_control old = cpu_smt_control;
+
+ ret = cpuhp_smt_enable();
+ if (ret)
+ goto out;
+ ret = cpuhp_smt_disable(old);
+ if (ret)
+ goto out;
+ }
+out:
+ cpu_hotplug_disable();
+ return ret;
+}