diff options
| author | Jiang Liu <jiang.liu@huawei.com> | 2013-09-27 09:04:41 +0100 |
|---|---|---|
| committer | Mark Brown <broonie@linaro.org> | 2014-06-19 12:33:49 +0100 |
| commit | 2f36c2ef1393d17dd2dde3458a55f804e0c10eac (patch) | |
| tree | e7863d706686e86263bc7188d0422f85cee2837d | |
| parent | df40a738827ebc244d552261fca865c98cd35e61 (diff) | |
arm64: fix possible invalid FPSIMD initialization state
If context switching happens during executing fpsimd_flush_thread(),
stale value in FPSIMD registers will be saved into current thread's
fpsimd_state by fpsimd_thread_switch(). That may cause invalid
initialization state for the new process, so disable preemption
when executing fpsimd_flush_thread().
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Jiang Liu <liuj97@gmail.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 6db83cea1c975b9a102e17def7d2795814e1ae2b)
Signed-off-by: Mark Brown <broonie@linaro.org>
| -rw-r--r-- | arch/arm64/kernel/fpsimd.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 1f2e4d5a5c0f..bb785d23dbde 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -80,8 +80,10 @@ void fpsimd_thread_switch(struct task_struct *next) void fpsimd_flush_thread(void) { + preempt_disable(); memset(¤t->thread.fpsimd_state, 0, sizeof(struct fpsimd_state)); fpsimd_load_state(¤t->thread.fpsimd_state); + preempt_enable(); } #ifdef CONFIG_KERNEL_MODE_NEON |