summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--arch/arm64/include/asm/processor.h3
-rw-r--r--arch/arm64/kernel/process.c8
-rw-r--r--arch/arm64/kernel/ptrace.c4
3 files changed, 13 insertions, 2 deletions
diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h
index 9428b93fefb2..64c9e78f9882 100644
--- a/arch/arm64/include/asm/processor.h
+++ b/arch/arm64/include/asm/processor.h
@@ -104,6 +104,9 @@ struct thread_struct {
#define task_user_tls(t) (&(t)->thread.tp_value)
#endif
+/* Sync TPIDR_EL0 back to thread_struct for current */
+void tls_preserve_current_state(void);
+
#define INIT_THREAD { }
static inline void start_thread_common(struct pt_regs *regs, unsigned long pc)
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index af1ea258c212..659ae8094ed5 100644
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -298,12 +298,16 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start,
return 0;
}
+void tls_preserve_current_state(void)
+{
+ *task_user_tls(current) = read_sysreg(tpidr_el0);
+}
+
static void tls_thread_switch(struct task_struct *next)
{
unsigned long tpidr, tpidrro;
- tpidr = read_sysreg(tpidr_el0);
- *task_user_tls(current) = tpidr;
+ tls_preserve_current_state();
tpidr = *task_user_tls(next);
tpidrro = is_compat_thread(task_thread_info(next)) ?
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index eeef01a219a6..35846f1550db 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -652,6 +652,10 @@ static int tls_get(struct task_struct *target, const struct user_regset *regset,
void *kbuf, void __user *ubuf)
{
unsigned long *tls = &target->thread.tp_value;
+
+ if (target == current)
+ tls_preserve_current_state();
+
return user_regset_copyout(&pos, &count, &kbuf, &ubuf, tls, 0, -1);
}