X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=arch%2Fmips%2Fkernel%2Funaligned.c;h=8b9c34ffae184fecf7fe720eaa0b596305194fe9;hb=8b805ef617cf0e02f6d18b891f8deb6246421b01;hp=a7d49ae805b43636ca49311a14ab14d4c2434364;hpb=df6d3916f3b7b7e2067567a256dd4f0c1ea854a2;p=linux-2.6-omap-h63xx.git diff --git a/arch/mips/kernel/unaligned.c b/arch/mips/kernel/unaligned.c index a7d49ae805b..bf4c4a979ab 100644 --- a/arch/mips/kernel/unaligned.c +++ b/arch/mips/kernel/unaligned.c @@ -76,7 +76,8 @@ #include #include #include - +#include +#include #include #include #include @@ -87,20 +88,27 @@ #define STR(x) __STR(x) #define __STR(x) #x -#ifdef CONFIG_PROC_FS -unsigned long unaligned_instructions; +enum { + UNALIGNED_ACTION_QUIET, + UNALIGNED_ACTION_SIGNAL, + UNALIGNED_ACTION_SHOW, +}; +#ifdef CONFIG_DEBUG_FS +static u32 unaligned_instructions; +static u32 unaligned_action; +#else +#define unaligned_action UNALIGNED_ACTION_QUIET #endif +extern void show_registers(struct pt_regs *regs); -static inline int emulate_load_store_insn(struct pt_regs *regs, - void __user *addr, unsigned int __user *pc, - unsigned long **regptr, unsigned long *newvalue) +static void emulate_load_store_insn(struct pt_regs *regs, + void __user *addr, unsigned int __user *pc) { union mips_instruction insn; unsigned long value; unsigned int res; regs->regs[0] = 0; - *regptr=NULL; /* * This load never faults. @@ -169,8 +177,8 @@ static inline int emulate_load_store_insn(struct pt_regs *regs, : "r" (addr), "i" (-EFAULT)); if (res) goto fault; - *newvalue = value; - *regptr = ®s->regs[insn.i_format.rt]; + compute_return_epc(regs); + regs->regs[insn.i_format.rt] = value; break; case lw_op: @@ -199,8 +207,8 @@ static inline int emulate_load_store_insn(struct pt_regs *regs, : "r" (addr), "i" (-EFAULT)); if (res) goto fault; - *newvalue = value; - *regptr = ®s->regs[insn.i_format.rt]; + compute_return_epc(regs); + regs->regs[insn.i_format.rt] = value; break; case lhu_op: @@ -233,8 +241,8 @@ static inline int emulate_load_store_insn(struct pt_regs *regs, : "r" (addr), "i" (-EFAULT)); if (res) goto fault; - *newvalue = value; - *regptr = ®s->regs[insn.i_format.rt]; + compute_return_epc(regs); + regs->regs[insn.i_format.rt] = value; break; case lwu_op: @@ -273,8 +281,8 @@ static inline int emulate_load_store_insn(struct pt_regs *regs, : "r" (addr), "i" (-EFAULT)); if (res) goto fault; - *newvalue = value; - *regptr = ®s->regs[insn.i_format.rt]; + compute_return_epc(regs); + regs->regs[insn.i_format.rt] = value; break; #endif /* CONFIG_64BIT */ @@ -315,8 +323,8 @@ static inline int emulate_load_store_insn(struct pt_regs *regs, : "r" (addr), "i" (-EFAULT)); if (res) goto fault; - *newvalue = value; - *regptr = ®s->regs[insn.i_format.rt]; + compute_return_epc(regs); + regs->regs[insn.i_format.rt] = value; break; #endif /* CONFIG_64BIT */ @@ -357,6 +365,7 @@ static inline int emulate_load_store_insn(struct pt_regs *regs, : "r" (value), "r" (addr), "i" (-EFAULT)); if (res) goto fault; + compute_return_epc(regs); break; case sw_op: @@ -387,6 +396,7 @@ static inline int emulate_load_store_insn(struct pt_regs *regs, : "r" (value), "r" (addr), "i" (-EFAULT)); if (res) goto fault; + compute_return_epc(regs); break; case sd_op: @@ -425,6 +435,7 @@ static inline int emulate_load_store_insn(struct pt_regs *regs, : "r" (value), "r" (addr), "i" (-EFAULT)); if (res) goto fault; + compute_return_epc(regs); break; #endif /* CONFIG_64BIT */ @@ -459,53 +470,38 @@ static inline int emulate_load_store_insn(struct pt_regs *regs, goto sigill; } -#ifdef CONFIG_PROC_FS +#ifdef CONFIG_DEBUG_FS unaligned_instructions++; #endif - return 0; + return; fault: /* Did we have an exception handler installed? */ if (fixup_exception(regs)) - return 1; + return; - die_if_kernel ("Unhandled kernel unaligned access", regs); + die_if_kernel("Unhandled kernel unaligned access", regs); send_sig(SIGSEGV, current, 1); - return 0; + return; sigbus: die_if_kernel("Unhandled kernel unaligned access", regs); send_sig(SIGBUS, current, 1); - return 0; + return; sigill: die_if_kernel("Unhandled kernel unaligned access or invalid instruction", regs); send_sig(SIGILL, current, 1); - - return 0; } asmlinkage void do_ade(struct pt_regs *regs) { - unsigned long *regptr, newval; - extern int do_dsemulret(struct pt_regs *); unsigned int __user *pc; mm_segment_t seg; - /* - * Address errors may be deliberately induced by the FPU emulator to - * retake control of the CPU after executing the instruction in the - * delay slot of an emulated branch. - */ - /* Terminate if exception was recognized as a delay slot return */ - if (do_dsemulret(regs)) - return; - - /* Otherwise handle as normal */ - /* * Did we catch a fault trying to load an instruction? * Or are we running in MIPS16 mode? @@ -514,8 +510,12 @@ asmlinkage void do_ade(struct pt_regs *regs) goto sigbus; pc = (unsigned int __user *) exception_epc(regs); - if (user_mode(regs) && (current->thread.mflags & MF_FIXADE) == 0) + if (user_mode(regs) && !test_thread_flag(TIF_FIXADE)) goto sigbus; + if (unaligned_action == UNALIGNED_ACTION_SIGNAL) + goto sigbus; + else if (unaligned_action == UNALIGNED_ACTION_SHOW) + show_registers(regs); /* * Do branch emulation only if we didn't forward the exception. @@ -524,16 +524,7 @@ asmlinkage void do_ade(struct pt_regs *regs) seg = get_fs(); if (!user_mode(regs)) set_fs(KERNEL_DS); - if (!emulate_load_store_insn(regs, (void __user *)regs->cp0_badvaddr, pc, - ®ptr, &newval)) { - compute_return_epc(regs); - /* - * Now that branch is evaluated, update the dest - * register if necessary - */ - if (regptr) - *regptr = newval; - } + emulate_load_store_insn(regs, (void __user *)regs->cp0_badvaddr, pc); set_fs(seg); return; @@ -546,3 +537,24 @@ sigbus: * XXX On return from the signal handler we should advance the epc */ } + +#ifdef CONFIG_DEBUG_FS +extern struct dentry *mips_debugfs_dir; +static int __init debugfs_unaligned(void) +{ + struct dentry *d; + + if (!mips_debugfs_dir) + return -ENODEV; + d = debugfs_create_u32("unaligned_instructions", S_IRUGO, + mips_debugfs_dir, &unaligned_instructions); + if (!d) + return -ENOMEM; + d = debugfs_create_u32("unaligned_action", S_IRUGO | S_IWUSR, + mips_debugfs_dir, &unaligned_action); + if (!d) + return -ENOMEM; + return 0; +} +__initcall(debugfs_unaligned); +#endif