diff options
Diffstat (limited to 'arch/mips/kernel/traps.c')
| -rw-r--r-- | arch/mips/kernel/traps.c | 72 |
1 files changed, 39 insertions, 33 deletions
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index b9a910b208f9..3905003dfe2b 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -708,6 +708,32 @@ asmlinkage void do_ov(struct pt_regs *regs) exception_exit(prev_state); } +/* + * Send SIGFPE according to FCSR Cause bits, which must have already + * been masked against Enable bits. This is impotant as Inexact can + * happen together with Overflow or Underflow, and `ptrace' can set + * any bits. + */ +void force_fcr31_sig(unsigned long fcr31, void __user *fault_addr, + struct task_struct *tsk) +{ + struct siginfo si = { .si_addr = fault_addr, .si_signo = SIGFPE }; + + if (fcr31 & FPU_CSR_INV_X) + si.si_code = FPE_FLTINV; + else if (fcr31 & FPU_CSR_DIV_X) + si.si_code = FPE_FLTDIV; + else if (fcr31 & FPU_CSR_OVF_X) + si.si_code = FPE_FLTOVF; + else if (fcr31 & FPU_CSR_UDF_X) + si.si_code = FPE_FLTUND; + else if (fcr31 & FPU_CSR_INE_X) + si.si_code = FPE_FLTRES; + else + si.si_code = __SI_FAULT; + force_sig_info(SIGFPE, &si, tsk); +} + int process_fpemu_return(int sig, void __user *fault_addr, unsigned long fcr31) { struct siginfo si = { 0 }; @@ -718,27 +744,7 @@ int process_fpemu_return(int sig, void __user *fault_addr, unsigned long fcr31) return 0; case SIGFPE: - si.si_addr = fault_addr; - si.si_signo = sig; - /* - * Inexact can happen together with Overflow or Underflow. - * Respect the mask to deliver the correct exception. - */ - fcr31 &= (fcr31 & FPU_CSR_ALL_E) << - (ffs(FPU_CSR_ALL_X) - ffs(FPU_CSR_ALL_E)); - if (fcr31 & FPU_CSR_INV_X) - si.si_code = FPE_FLTINV; - else if (fcr31 & FPU_CSR_DIV_X) - si.si_code = FPE_FLTDIV; - else if (fcr31 & FPU_CSR_OVF_X) - si.si_code = FPE_FLTOVF; - else if (fcr31 & FPU_CSR_UDF_X) - si.si_code = FPE_FLTUND; - else if (fcr31 & FPU_CSR_INE_X) - si.si_code = FPE_FLTRES; - else - si.si_code = __SI_FAULT; - force_sig_info(sig, &si, current); + force_fcr31_sig(fcr31, fault_addr, current); return 1; case SIGBUS: @@ -802,13 +808,13 @@ static int simulate_fp(struct pt_regs *regs, unsigned int opcode, /* Run the emulator */ sig = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1, &fault_addr); - fcr31 = current->thread.fpu.fcr31; /* - * We can't allow the emulated instruction to leave any of - * the cause bits set in $fcr31. + * We can't allow the emulated instruction to leave any + * enabled Cause bits set in $fcr31. */ - current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X; + fcr31 = mask_fcr31_x(current->thread.fpu.fcr31); + current->thread.fpu.fcr31 &= ~fcr31; /* Restore the hardware register state */ own_fpu(1); @@ -834,7 +840,7 @@ asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31) goto out; /* Clear FCSR.Cause before enabling interrupts */ - write_32bit_cp1_register(CP1_STATUS, fcr31 & ~FPU_CSR_ALL_X); + write_32bit_cp1_register(CP1_STATUS, fcr31 & ~mask_fcr31_x(fcr31)); local_irq_enable(); die_if_kernel("FP exception in kernel code", regs); @@ -856,13 +862,13 @@ asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31) /* Run the emulator */ sig = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1, &fault_addr); - fcr31 = current->thread.fpu.fcr31; /* - * We can't allow the emulated instruction to leave any of - * the cause bits set in $fcr31. + * We can't allow the emulated instruction to leave any + * enabled Cause bits set in $fcr31. */ - current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X; + fcr31 = mask_fcr31_x(current->thread.fpu.fcr31); + current->thread.fpu.fcr31 &= ~fcr31; /* Restore the hardware register state */ own_fpu(1); /* Using the FPU again. */ @@ -1427,13 +1433,13 @@ asmlinkage void do_cpu(struct pt_regs *regs) sig = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 0, &fault_addr); - fcr31 = current->thread.fpu.fcr31; /* * We can't allow the emulated instruction to leave - * any of the cause bits set in $fcr31. + * any enabled Cause bits set in $fcr31. */ - current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X; + fcr31 = mask_fcr31_x(current->thread.fpu.fcr31); + current->thread.fpu.fcr31 &= ~fcr31; /* Send a signal if required. */ if (!process_fpemu_return(sig, fault_addr, fcr31) && !err) |