diff options
| -rw-r--r-- | arch/mips/kernel/unaligned.c | 255 |
1 files changed, 255 insertions, 0 deletions
diff --git a/arch/mips/kernel/unaligned.c b/arch/mips/kernel/unaligned.c index 0213906e3f8..203d8857070 100644 --- a/arch/mips/kernel/unaligned.c +++ b/arch/mips/kernel/unaligned.c @@ -1304,6 +1304,250 @@ sigill: force_sig(SIGILL, current); } +static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr) +{ + unsigned long value; + unsigned int res; + int reg; + unsigned long orig31; + u16 __user *pc16; + unsigned long origpc; + union mips16e_instruction mips16inst, oldinst; + + origpc = regs->cp0_epc; + orig31 = regs->regs[31]; + pc16 = (unsigned short __user *)msk_isa16_mode(origpc); + /* + * This load never faults. + */ + __get_user(mips16inst.full, pc16); + oldinst = mips16inst; + + /* skip EXTEND instruction */ + if (mips16inst.ri.opcode == MIPS16e_extend_op) { + pc16++; + __get_user(mips16inst.full, pc16); + } else if (delay_slot(regs)) { + /* skip jump instructions */ + /* JAL/JALX are 32 bits but have OPCODE in first short int */ + if (mips16inst.ri.opcode == MIPS16e_jal_op) + pc16++; + pc16++; + if (get_user(mips16inst.full, pc16)) + goto sigbus; + } + + switch (mips16inst.ri.opcode) { + case MIPS16e_i64_op: /* I64 or RI64 instruction */ + switch (mips16inst.i64.func) { /* I64/RI64 func field check */ + case MIPS16e_ldpc_func: + case MIPS16e_ldsp_func: + reg = reg16to32[mips16inst.ri64.ry]; + goto loadDW; + + case MIPS16e_sdsp_func: + reg = reg16to32[mips16inst.ri64.ry]; + goto writeDW; + + case MIPS16e_sdrasp_func: + reg = 29; /* GPRSP */ + goto writeDW; + } + + goto sigbus; + + case MIPS16e_swsp_op: + case MIPS16e_lwpc_op: + case MIPS16e_lwsp_op: + reg = reg16to32[mips16inst.ri.rx]; + break; + + case MIPS16e_i8_op: + if (mips16inst.i8.func != MIPS16e_swrasp_func) + goto sigbus; + reg = 29; /* GPRSP */ + break; + + default: + reg = reg16to32[mips16inst.rri.ry]; + break; + } + + switch (mips16inst.ri.opcode) { + + case MIPS16e_lb_op: + case MIPS16e_lbu_op: + case MIPS16e_sb_op: + goto sigbus; + + case MIPS16e_lh_op: + if (!access_ok(VERIFY_READ, addr, 2)) + goto sigbus; + + LoadHW(addr, value, res); + if (res) + goto fault; + MIPS16e_compute_return_epc(regs, &oldinst); + regs->regs[reg] = value; + break; + + case MIPS16e_lhu_op: + if (!access_ok(VERIFY_READ, addr, 2)) + goto sigbus; + + LoadHWU(addr, value, res); + if (res) + goto fault; + MIPS16e_compute_return_epc(regs, &oldinst); + regs->regs[reg] = value; + break; + + case MIPS16e_lw_op: + case MIPS16e_lwpc_op: + case MIPS16e_lwsp_op: + if (!access_ok(VERIFY_READ, addr, 4)) + goto sigbus; + + LoadW(addr, value, res); + if (res) + goto fault; + MIPS16e_compute_return_epc(regs, &oldinst); + regs->regs[reg] = value; + break; + + case MIPS16e_lwu_op: +#ifdef CONFIG_64BIT + /* + * A 32-bit kernel might be running on a 64-bit processor. But + * if we're on a 32-bit processor and an i-cache incoherency + * or race makes us see a 64-bit instruction here the sdl/sdr + * would blow up, so for now we don't handle unaligned 64-bit + * instructions on 32-bit kernels. + */ + if (!access_ok(VERIFY_READ, addr, 4)) + goto sigbus; + + LoadWU(addr, value, res); + if (res) + goto fault; + MIPS16e_compute_return_epc(regs, &oldinst); + regs->regs[reg] = value; + break; +#endif /* CONFIG_64BIT */ + + /* Cannot handle 64-bit instructions in 32-bit kernel */ + goto sigill; + + case MIPS16e_ld_op: +loadDW: +#ifdef CONFIG_64BIT + /* + * A 32-bit kernel might be running on a 64-bit processor. But + * if we're on a 32-bit processor and an i-cache incoherency + * or race makes us see a 64-bit instruction here the sdl/sdr + * would blow up, so for now we don't handle unaligned 64-bit + * instructions on 32-bit kernels. + */ + if (!access_ok(VERIFY_READ, addr, 8)) + goto sigbus; + + LoadDW(addr, value, res); + if (res) + goto fault; + MIPS16e_compute_return_epc(regs, &oldinst); + regs->regs[reg] = value; + break; +#endif /* CONFIG_64BIT */ + + /* Cannot handle 64-bit instructions in 32-bit kernel */ + goto sigill; + + case MIPS16e_sh_op: + if (!access_ok(VERIFY_WRITE, addr, 2)) + goto sigbus; + + MIPS16e_compute_return_epc(regs, &oldinst); + value = regs->regs[reg]; + StoreHW(addr, value, res); + if (res) + goto fault; + break; + + case MIPS16e_sw_op: + case MIPS16e_swsp_op: + case MIPS16e_i8_op: /* actually - MIPS16e_swrasp_func */ + if (!access_ok(VERIFY_WRITE, addr, 4)) + goto sigbus; + + MIPS16e_compute_return_epc(regs, &oldinst); + value = regs->regs[reg]; + StoreW(addr, value, res); + if (res) + goto fault; + break; + + case MIPS16e_sd_op: +writeDW: +#ifdef CONFIG_64BIT + /* + * A 32-bit kernel might be running on a 64-bit processor. But + * if we're on a 32-bit processor and an i-cache incoherency + * or race makes us see a 64-bit instruction here the sdl/sdr + * would blow up, so for now we don't handle unaligned 64-bit + * instructions on 32-bit kernels. + */ + if (!access_ok(VERIFY_WRITE, addr, 8)) + goto sigbus; + + MIPS16e_compute_return_epc(regs, &oldinst); + value = regs->regs[reg]; + StoreDW(addr, value, res); + if (res) + goto fault; + break; +#endif /* CONFIG_64BIT */ + + /* Cannot handle 64-bit instructions in 32-bit kernel */ + goto sigill; + + default: + /* + * Pheeee... We encountered an yet unknown instruction or + * cache coherence problem. Die sucker, die ... + */ + goto sigill; + } + +#ifdef CONFIG_DEBUG_FS + unaligned_instructions++; +#endif + + return; + +fault: + /* roll back jump/branch */ + regs->cp0_epc = origpc; + regs->regs[31] = orig31; + /* Did we have an exception handler installed? */ + if (fixup_exception(regs)) + return; + + die_if_kernel("Unhandled kernel unaligned access", regs); + force_sig(SIGSEGV, current); + + return; + +sigbus: + die_if_kernel("Unhandled kernel unaligned access", regs); + force_sig(SIGBUS, current); + + return; + +sigill: + die_if_kernel + ("Unhandled kernel unaligned access or invalid instruction", regs); + force_sig(SIGILL, current); +} asmlinkage void do_ade(struct pt_regs *regs) { unsigned int __user *pc; @@ -1351,6 +1595,17 @@ asmlinkage void do_ade(struct pt_regs *regs) return; } + if (cpu_has_mips16) { + seg = get_fs(); + if (!user_mode(regs)) + set_fs(KERNEL_DS); + emulate_load_store_MIPS16e(regs, + (void __user *)regs->cp0_badvaddr); + set_fs(seg); + + return; + } + goto sigbus; } |