diff options
Diffstat (limited to 'arch/mips/kernel/traps.c')
| -rw-r--r-- | arch/mips/kernel/traps.c | 93 |
1 files changed, 78 insertions, 15 deletions
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index c3b41e24c05a..5b4d711f878d 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -46,6 +46,7 @@ #include <asm/fpu.h> #include <asm/fpu_emulator.h> #include <asm/idle.h> +#include <asm/mips-r2-to-r6-emul.h> #include <asm/mipsregs.h> #include <asm/mipsmtregs.h> #include <asm/module.h> @@ -700,6 +701,13 @@ asmlinkage void do_ov(struct pt_regs *regs) int process_fpemu_return(int sig, void __user *fault_addr) { + /* + * We can't allow the emulated instruction to leave any of the cause + * bits set in FCSR. If they were then the kernel would take an FP + * exception when restoring FP context. + */ + current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X; + if (sig == SIGSEGV || sig == SIGBUS) { struct siginfo si = {0}; si.si_addr = fault_addr; @@ -780,6 +788,11 @@ asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31) if (notify_die(DIE_FP, "FP exception", regs, 0, regs_to_trapnr(regs), SIGFPE) == NOTIFY_STOP) goto out; + + /* Clear FCSR.Cause before enabling interrupts */ + write_32bit_cp1_register(CP1_STATUS, fcr31 & ~FPU_CSR_ALL_X); + local_irq_enable(); + die_if_kernel("FP exception in kernel code", regs); if (fcr31 & FPU_CSR_UNI_X) { @@ -803,18 +816,12 @@ asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31) sig = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1, &fault_addr); - /* - * We can't allow the emulated instruction to leave any of - * the cause bit set in $fcr31. - */ - current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X; + /* If something went wrong, signal */ + process_fpemu_return(sig, fault_addr); /* Restore the hardware register state */ own_fpu(1); /* Using the FPU again. */ - /* If something went wrong, signal */ - process_fpemu_return(sig, fault_addr); - goto out; } else if (fcr31 & FPU_CSR_INV_X) info.si_code = FPE_FLTINV; @@ -837,7 +844,7 @@ out: exception_exit(prev_state); } -static void do_trap_or_bp(struct pt_regs *regs, unsigned int code, +void do_trap_or_bp(struct pt_regs *regs, unsigned int code, const char *str) { siginfo_t info; @@ -1027,7 +1034,34 @@ asmlinkage void do_ri(struct pt_regs *regs) unsigned int opcode = 0; int status = -1; + /* + * Avoid any kernel code. Just emulate the R2 instruction + * as quickly as possible. + */ + if (mipsr2_emulation && cpu_has_mips_r6 && + likely(user_mode(regs))) { + if (likely(get_user(opcode, epc) >= 0)) { + status = mipsr2_decoder(regs, opcode); + switch (status) { + case 0: + case SIGEMT: + task_thread_info(current)->r2_emul_return = 1; + return; + case SIGILL: + goto no_r2_instr; + default: + process_fpemu_return(status, + ¤t->thread.cp0_baduaddr); + task_thread_info(current)->r2_emul_return = 1; + return; + } + } + } + +no_r2_instr: + prev_state = exception_enter(); + if (notify_die(DIE_RI, "RI Fault", regs, 0, regs_to_trapnr(regs), SIGILL) == NOTIFY_STOP) goto out; @@ -1134,10 +1168,29 @@ static int default_cu2_call(struct notifier_block *nfb, unsigned long action, return NOTIFY_OK; } +static int wait_on_fp_mode_switch(atomic_t *p) +{ + /* + * The FP mode for this task is currently being switched. That may + * involve modifications to the format of this tasks FP context which + * make it unsafe to proceed with execution for the moment. Instead, + * schedule some other task. + */ + schedule(); + return 0; +} + static int enable_restore_fp_context(int msa) { int err, was_fpu_owner, prior_msa; + /* + * If an FP mode switch is currently underway, wait for it to + * complete before proceeding. + */ + wait_on_atomic_t(¤t->mm->context.fp_mode_switching, + wait_on_fp_mode_switch, TASK_KILLABLE); + if (!used_math()) { /* First time FP context user. */ preempt_disable(); @@ -1345,13 +1398,22 @@ out: exception_exit(prev_state); } -asmlinkage void do_msa_fpe(struct pt_regs *regs) +asmlinkage void do_msa_fpe(struct pt_regs *regs, unsigned int msacsr) { enum ctx_state prev_state; prev_state = exception_enter(); + if (notify_die(DIE_MSAFP, "MSA FP exception", regs, 0, + regs_to_trapnr(regs), SIGFPE) == NOTIFY_STOP) + goto out; + + /* Clear MSACSR.Cause before enabling interrupts */ + write_msa_csr(msacsr & ~MSA_CSR_CAUSEF); + local_irq_enable(); + die_if_kernel("do_msa_fpe invoked from kernel context!", regs); force_sig(SIGFPE, current); +out: exception_exit(prev_state); } @@ -1541,6 +1603,7 @@ static inline void parity_protection_init(void) case CPU_INTERAPTIV: case CPU_PROAPTIV: case CPU_P5600: + case CPU_QEMU_GENERIC: { #define ERRCTL_PE 0x80000000 #define ERRCTL_L2P 0x00800000 @@ -1630,7 +1693,7 @@ asmlinkage void cache_parity_error(void) printk("Decoded c0_cacheerr: %s cache fault in %s reference.\n", reg_val & (1<<30) ? "secondary" : "primary", reg_val & (1<<31) ? "data" : "insn"); - if (cpu_has_mips_r2 && + if ((cpu_has_mips_r2_r6) && ((current_cpu_data.processor_id & 0xff0000) == PRID_COMP_MIPS)) { pr_err("Error bits: %s%s%s%s%s%s%s%s\n", reg_val & (1<<29) ? "ED " : "", @@ -1670,7 +1733,7 @@ asmlinkage void do_ftlb(void) unsigned int reg_val; /* For the moment, report the problem and hang. */ - if (cpu_has_mips_r2 && + if ((cpu_has_mips_r2_r6) && ((current_cpu_data.processor_id & 0xff0000) == PRID_COMP_MIPS)) { pr_err("FTLB error exception, cp0_ecc=0x%08x:\n", read_c0_ecc()); @@ -1959,7 +2022,7 @@ static void configure_hwrena(void) { unsigned int hwrena = cpu_hwrena_impl_bits; - if (cpu_has_mips_r2) + if (cpu_has_mips_r2_r6) hwrena |= 0x0000000f; if (!noulri && cpu_has_userlocal) @@ -2003,7 +2066,7 @@ void per_cpu_trap_init(bool is_boot_cpu) * o read IntCtl.IPTI to determine the timer interrupt * o read IntCtl.IPPCI to determine the performance counter interrupt */ - if (cpu_has_mips_r2) { + if (cpu_has_mips_r2_r6) { cp0_compare_irq_shift = CAUSEB_TI - CAUSEB_IP; cp0_compare_irq = (read_c0_intctl() >> INTCTLB_IPTI) & 7; cp0_perfcount_irq = (read_c0_intctl() >> INTCTLB_IPPCI) & 7; @@ -2094,7 +2157,7 @@ void __init trap_init(void) #else ebase = CKSEG0; #endif - if (cpu_has_mips_r2) + if (cpu_has_mips_r2_r6) ebase += (read_c0_ebase() & 0x3ffff000); } |
