diff options
Diffstat (limited to 'arch/powerpc/kernel/traps.c')
| -rw-r--r-- | arch/powerpc/kernel/traps.c | 111 |
1 files changed, 75 insertions, 36 deletions
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 535f50665647..dcc6f159fd94 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -174,7 +174,7 @@ void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr) * generate the same exception over and over again and we get * nowhere. Better to kill it and let the kernel panic. */ - if (current->pid == 1) { + if (is_init(current)) { __sighandler_t handler; spin_lock_irq(¤t->sighand->siglock); @@ -535,34 +535,40 @@ static void emulate_single_step(struct pt_regs *regs) } } -static void parse_fpe(struct pt_regs *regs) +static inline int __parse_fpscr(unsigned long fpscr) { - int code = 0; - unsigned long fpscr; - - flush_fp_to_thread(current); - - fpscr = current->thread.fpscr.val; + int ret = 0; /* Invalid operation */ if ((fpscr & FPSCR_VE) && (fpscr & FPSCR_VX)) - code = FPE_FLTINV; + ret = FPE_FLTINV; /* Overflow */ else if ((fpscr & FPSCR_OE) && (fpscr & FPSCR_OX)) - code = FPE_FLTOVF; + ret = FPE_FLTOVF; /* Underflow */ else if ((fpscr & FPSCR_UE) && (fpscr & FPSCR_UX)) - code = FPE_FLTUND; + ret = FPE_FLTUND; /* Divide by zero */ else if ((fpscr & FPSCR_ZE) && (fpscr & FPSCR_ZX)) - code = FPE_FLTDIV; + ret = FPE_FLTDIV; /* Inexact result */ else if ((fpscr & FPSCR_XE) && (fpscr & FPSCR_XX)) - code = FPE_FLTRES; + ret = FPE_FLTRES; + + return ret; +} + +static void parse_fpe(struct pt_regs *regs) +{ + int code = 0; + + flush_fp_to_thread(current); + + code = __parse_fpscr(current->thread.fpscr.val); _exception(SIGFPE, regs, code, regs->nip); } @@ -739,20 +745,7 @@ void __kprobes program_check_exception(struct pt_regs *regs) extern int do_mathemu(struct pt_regs *regs); /* We can now get here via a FP Unavailable exception if the core - * has no FPU, in that case no reason flags will be set */ -#ifdef CONFIG_MATH_EMULATION - /* (reason & REASON_ILLEGAL) would be the obvious thing here, - * but there seems to be a hardware bug on the 405GP (RevD) - * that means ESR is sometimes set incorrectly - either to - * ESR_DST (!?) or 0. In the process of chasing this with the - * hardware people - not sure if it can happen on any illegal - * instruction or only on FP instructions, whether there is a - * pattern to occurences etc. -dgibson 31/Mar/2003 */ - if (!(reason & REASON_TRAP) && do_mathemu(regs) == 0) { - emulate_single_step(regs); - return; - } -#endif /* CONFIG_MATH_EMULATION */ + * has no FPU, in that case the reason flags will be 0 */ if (reason & REASON_FP) { /* IEEE FP exception */ @@ -778,6 +771,31 @@ void __kprobes program_check_exception(struct pt_regs *regs) local_irq_enable(); +#ifdef CONFIG_MATH_EMULATION + /* (reason & REASON_ILLEGAL) would be the obvious thing here, + * but there seems to be a hardware bug on the 405GP (RevD) + * that means ESR is sometimes set incorrectly - either to + * ESR_DST (!?) or 0. In the process of chasing this with the + * hardware people - not sure if it can happen on any illegal + * instruction or only on FP instructions, whether there is a + * pattern to occurences etc. -dgibson 31/Mar/2003 */ + switch (do_mathemu(regs)) { + case 0: + emulate_single_step(regs); + return; + case 1: { + int code = 0; + code = __parse_fpscr(current->thread.fpscr.val); + _exception(SIGFPE, regs, code, regs->nip); + return; + } + case -EFAULT: + _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip); + return; + } + /* fall through on any other errors */ +#endif /* CONFIG_MATH_EMULATION */ + /* Try to emulate it if we should. */ if (reason & (REASON_ILLEGAL | REASON_PRIVILEGED)) { switch (emulate_instruction(regs)) { @@ -891,18 +909,39 @@ void SoftwareEmulation(struct pt_regs *regs) #ifdef CONFIG_MATH_EMULATION errcode = do_mathemu(regs); + + switch (errcode) { + case 0: + emulate_single_step(regs); + return; + case 1: { + int code = 0; + code = __parse_fpscr(current->thread.fpscr.val); + _exception(SIGFPE, regs, code, regs->nip); + return; + } + case -EFAULT: + _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip); + return; + default: + _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); + return; + } + #else errcode = Soft_emulate_8xx(regs); -#endif - if (errcode) { - if (errcode > 0) - _exception(SIGFPE, regs, 0, 0); - else if (errcode == -EFAULT) - _exception(SIGSEGV, regs, 0, 0); - else - _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); - } else + switch (errcode) { + case 0: emulate_single_step(regs); + return; + case 1: + _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); + return; + case -EFAULT: + _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip); + return; + } +#endif } #endif /* CONFIG_8xx */ |