diff options
Diffstat (limited to 'arch/mips/include/asm')
-rw-r--r-- | arch/mips/include/asm/fpu_emulator.h | 13 | ||||
-rw-r--r-- | arch/mips/include/asm/switch_to.h | 18 |
2 files changed, 31 insertions, 0 deletions
diff --git a/arch/mips/include/asm/fpu_emulator.h b/arch/mips/include/asm/fpu_emulator.h index 355dc25172e7..c05369e0b8d6 100644 --- a/arch/mips/include/asm/fpu_emulator.h +++ b/arch/mips/include/asm/fpu_emulator.h @@ -63,6 +63,8 @@ do { \ extern int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx, int has_fpu, void *__user *fault_addr); +void force_fcr31_sig(unsigned long fcr31, void __user *fault_addr, + struct task_struct *tsk); int process_fpemu_return(int sig, void __user *fault_addr, unsigned long fcr31); int isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn, @@ -81,4 +83,15 @@ static inline void fpu_emulator_init_fpu(void) set_fpr64(&t->thread.fpu.fpr[i], 0, SIGNALLING_NAN); } +/* + * Mask the FCSR Cause bits according to the Enable bits, observing + * that Unimplemented is always enabled. + */ +static inline unsigned long mask_fcr31_x(unsigned long fcr31) +{ + return fcr31 & (FPU_CSR_UNI_X | + ((fcr31 & FPU_CSR_ALL_E) << + (ffs(FPU_CSR_ALL_X) - ffs(FPU_CSR_ALL_E)))); +} + #endif /* _ASM_FPU_EMULATOR_H */ diff --git a/arch/mips/include/asm/switch_to.h b/arch/mips/include/asm/switch_to.h index ebb5c0f2f90d..c0ae27971e31 100644 --- a/arch/mips/include/asm/switch_to.h +++ b/arch/mips/include/asm/switch_to.h @@ -76,6 +76,22 @@ do { if (cpu_has_rw_llb) { \ } while (0) /* + * Check FCSR for any unmasked exceptions pending set with `ptrace', + * clear them and send a signal. + */ +#define __sanitize_fcr31(next) \ +do { \ + unsigned long fcr31 = mask_fcr31_x(next->thread.fpu.fcr31); \ + void __user *pc; \ + \ + if (unlikely(fcr31)) { \ + pc = (void __user *)task_pt_regs(next)->cp0_epc; \ + next->thread.fpu.fcr31 &= ~fcr31; \ + force_fcr31_sig(fcr31, pc, next); \ + } \ +} while (0) + +/* * For newly created kernel threads switch_to() will return to * ret_from_kernel_thread, newly created user threads to ret_from_fork. * That is, everything following resume() will be skipped for new threads. @@ -85,6 +101,8 @@ do { if (cpu_has_rw_llb) { \ do { \ __mips_mt_fpaff_switch_to(prev); \ lose_fpu_inatomic(1, prev); \ + if (tsk_used_math(next)) \ + __sanitize_fcr31(next); \ if (cpu_has_dsp) { \ __save_dsp(prev); \ __restore_dsp(next); \ |