diff options
| author | Jiang Liu <jiang.liu@huawei.com> | 2013-09-27 09:04:41 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-01-09 12:24:26 -0800 |
| commit | 2bf5861acf602fe6201ac1f82955ac7283e56b6f (patch) | |
| tree | a9ce744c6ef2bd2b42ac4a54d712e4f2fe6e22f1 /arch/arm64 | |
| parent | 79f783f05539479676406d3d42c3d86bd203f083 (diff) | |
arm64: fix possible invalid FPSIMD initialization state
commit 6db83cea1c975b9a102e17def7d2795814e1ae2b upstream.
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>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/arm64')
| -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 e8b8357aedb4..2fa308e4a1fa 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -79,8 +79,10 @@ 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(); } /* |