diff options
| -rw-r--r-- | arch/x86/kernel/i387.c | 12 | ||||
| -rw-r--r-- | include/asm-x86/i387.h | 10 |
2 files changed, 19 insertions, 3 deletions
diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c index db6839b53195..e03cc952f233 100644 --- a/arch/x86/kernel/i387.c +++ b/arch/x86/kernel/i387.c @@ -450,7 +450,6 @@ static inline int restore_i387_fsave(struct _fpstate_ia32 __user *buf) { struct task_struct *tsk = current; - clear_fpu(tsk); return __copy_from_user(&tsk->thread.xstate->fsave, buf, sizeof(struct i387_fsave_struct)); } @@ -461,7 +460,6 @@ static int restore_i387_fxsave(struct _fpstate_ia32 __user *buf) struct user_i387_ia32_struct env; int err; - clear_fpu(tsk); err = __copy_from_user(&tsk->thread.xstate->fxsave, &buf->_fxsr_env[0], sizeof(struct i387_fxsave_struct)); /* mxcsr reserved bits must be masked to zero for security reasons */ @@ -478,6 +476,16 @@ int restore_i387_ia32(struct _fpstate_ia32 __user *buf) int err; if (HAVE_HWFP) { + struct task_struct *tsk = current; + + clear_fpu(tsk); + + if (!used_math()) { + err = init_fpu(tsk); + if (err) + return err; + } + if (cpu_has_fxsr) err = restore_i387_fxsave(buf); else diff --git a/include/asm-x86/i387.h b/include/asm-x86/i387.h index da2adb45f6e3..6b722d315936 100644 --- a/include/asm-x86/i387.h +++ b/include/asm-x86/i387.h @@ -175,7 +175,15 @@ static inline int save_i387(struct _fpstate __user *buf) */ static inline int restore_i387(struct _fpstate __user *buf) { - set_used_math(); + struct task_struct *tsk = current; + int err; + + if (!used_math()) { + err = init_fpu(tsk); + if (err) + return err; + } + if (!(task_thread_info(current)->status & TS_USEDFPU)) { clts(); task_thread_info(current)->status |= TS_USEDFPU; |