diff options
| -rw-r--r-- | arch/riscv/include/asm/switch_to.h | 6 | ||||
| -rw-r--r-- | arch/riscv/kernel/process.c | 11 |
2 files changed, 15 insertions, 2 deletions
diff --git a/arch/riscv/include/asm/switch_to.h b/arch/riscv/include/asm/switch_to.h index 853b65ef656d..949d9cd91dec 100644 --- a/arch/riscv/include/asm/switch_to.h +++ b/arch/riscv/include/asm/switch_to.h @@ -19,6 +19,12 @@ static inline void __fstate_clean(struct pt_regs *regs) regs->sstatus |= (regs->sstatus & ~(SR_FS)) | SR_FS_CLEAN; } +static inline void fstate_off(struct task_struct *task, + struct pt_regs *regs) +{ + regs->sstatus = (regs->sstatus & ~SR_FS) | SR_FS_OFF; +} + static inline void fstate_save(struct task_struct *task, struct pt_regs *regs) { diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c index f23794bd1e90..fb3a082362eb 100644 --- a/arch/riscv/kernel/process.c +++ b/arch/riscv/kernel/process.c @@ -64,8 +64,14 @@ void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp) { regs->sstatus = SR_SPIE; - if (has_fpu) + if (has_fpu) { regs->sstatus |= SR_FS_INITIAL; + /* + * Restore the initial value to the FP register + * before starting the user program. + */ + fstate_restore(current, regs); + } regs->sepc = pc; regs->sp = sp; set_fs(USER_DS); @@ -75,10 +81,11 @@ void flush_thread(void) { #ifdef CONFIG_FPU /* - * Reset FPU context + * Reset FPU state and context * frm: round to nearest, ties to even (IEEE default) * fflags: accrued exceptions cleared */ + fstate_off(current, task_pt_regs(current)); memset(¤t->thread.fstate, 0, sizeof(current->thread.fstate)); #endif } |