Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64...

[linux-beck.git] / arch / arm64 / kernel / process.c

diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index bf669228a59f0cd134ef789129a22708846d758f..89f41f7d27dd2bc54da37bd850f5437f86b19630 100644 (file)
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -204,9 +204,27 @@ void exit_thread(void)
 {
 }
 
+static void tls_thread_flush(void)
+{
+       asm ("msr tpidr_el0, xzr");
+
+       if (is_compat_task()) {
+               current->thread.tp_value = 0;
+
+               /*
+                * We need to ensure ordering between the shadow state and the
+                * hardware state, so that we don't corrupt the hardware state
+                * with a stale shadow state during context switch.
+                */
+               barrier();
+               asm ("msr tpidrro_el0, xzr");
+       }
+}
+
 void flush_thread(void)
 {
        fpsimd_flush_thread();
+       tls_thread_flush();
        flush_ptrace_hw_breakpoint(current);
 }