diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kernel/i387.c | 31 |
1 files changed, 17 insertions, 14 deletions
diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c index 95079026c386..909d10d2fb70 100644 --- a/arch/x86/kernel/i387.c +++ b/arch/x86/kernel/i387.c @@ -283,27 +283,30 @@ EXPORT_SYMBOL_GPL(fpstate_alloc_init); * value at reset if we support XMM instructions and then * remember the current task has used the FPU. */ -static int init_fpu(struct task_struct *tsk) +static int fpu__unlazy_stopped(struct task_struct *child) { int ret; - if (tsk_used_math(tsk)) { - if (cpu_has_fpu && tsk == current) - fpu__save(tsk); - task_disable_lazy_fpu_restore(tsk); + if (WARN_ON_ONCE(child == current)) + return -EINVAL; + + if (tsk_used_math(child)) { + if (cpu_has_fpu && child == current) + fpu__save(child); + task_disable_lazy_fpu_restore(child); return 0; } /* * Memory allocation at the first usage of the FPU and other state. */ - ret = fpu_alloc(&tsk->thread.fpu); + ret = fpu_alloc(&child->thread.fpu); if (ret) return ret; - fpu_finit(&tsk->thread.fpu); + fpu_finit(&child->thread.fpu); - set_stopped_child_used_math(tsk); + set_stopped_child_used_math(child); return 0; } @@ -331,7 +334,7 @@ int xfpregs_get(struct task_struct *target, const struct user_regset *regset, if (!cpu_has_fxsr) return -ENODEV; - ret = init_fpu(target); + ret = fpu__unlazy_stopped(target); if (ret) return ret; @@ -350,7 +353,7 @@ int xfpregs_set(struct task_struct *target, const struct user_regset *regset, if (!cpu_has_fxsr) return -ENODEV; - ret = init_fpu(target); + ret = fpu__unlazy_stopped(target); if (ret) return ret; @@ -384,7 +387,7 @@ int xstateregs_get(struct task_struct *target, const struct user_regset *regset, if (!cpu_has_xsave) return -ENODEV; - ret = init_fpu(target); + ret = fpu__unlazy_stopped(target); if (ret) return ret; @@ -414,7 +417,7 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset, if (!cpu_has_xsave) return -ENODEV; - ret = init_fpu(target); + ret = fpu__unlazy_stopped(target); if (ret) return ret; @@ -577,7 +580,7 @@ int fpregs_get(struct task_struct *target, const struct user_regset *regset, struct user_i387_ia32_struct env; int ret; - ret = init_fpu(target); + ret = fpu__unlazy_stopped(target); if (ret) return ret; @@ -608,7 +611,7 @@ int fpregs_set(struct task_struct *target, const struct user_regset *regset, struct user_i387_ia32_struct env; int ret; - ret = init_fpu(target); + ret = fpu__unlazy_stopped(target); if (ret) return ret; |