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Diffstat (limited to 'arch/x86/include/asm/switch_to.h')
-rw-r--r--arch/x86/include/asm/switch_to.h12
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/x86/include/asm/switch_to.h b/arch/x86/include/asm/switch_to.h
index fcc5cd387fd1..7ae8caffbada 100644
--- a/arch/x86/include/asm/switch_to.h
+++ b/arch/x86/include/asm/switch_to.h
@@ -72,4 +72,16 @@ do { \
((last) = __switch_to_asm((prev), (next))); \
} while (0)
+#ifdef CONFIG_X86_32
+static inline void refresh_sysenter_cs(struct thread_struct *thread)
+{
+ /* Only happens when SEP is enabled, no need to test "SEP"arately: */
+ if (unlikely(this_cpu_read(cpu_tss.x86_tss.ss1) == thread->sysenter_cs))
+ return;
+
+ this_cpu_write(cpu_tss.x86_tss.ss1, thread->sysenter_cs);
+ wrmsr(MSR_IA32_SYSENTER_CS, thread->sysenter_cs, 0);
+}
+#endif
+
#endif /* _ASM_X86_SWITCH_TO_H */