diff options
Diffstat (limited to 'arch/ia64/kernel/traps.c')
| -rw-r--r-- | arch/ia64/kernel/traps.c | 612 |
1 files changed, 612 insertions, 0 deletions
diff --git a/arch/ia64/kernel/traps.c b/arch/ia64/kernel/traps.c new file mode 100644 index 000000000..53735b1d1 --- /dev/null +++ b/arch/ia64/kernel/traps.c @@ -0,0 +1,612 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Architecture-specific trap handling. + * + * Copyright (C) 1998-2003 Hewlett-Packard Co + * David Mosberger-Tang <davidm@hpl.hp.com> + * + * 05/12/00 grao <goutham.rao@intel.com> : added isr in siginfo for SIGFPE + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/sched/signal.h> +#include <linux/sched/debug.h> +#include <linux/tty.h> +#include <linux/vt_kern.h> /* For unblank_screen() */ +#include <linux/export.h> +#include <linux/extable.h> +#include <linux/hardirq.h> +#include <linux/kprobes.h> +#include <linux/delay.h> /* for ssleep() */ +#include <linux/kdebug.h> +#include <linux/uaccess.h> + +#include <asm/fpswa.h> +#include <asm/intrinsics.h> +#include <asm/processor.h> +#include <asm/exception.h> +#include <asm/setup.h> + +fpswa_interface_t *fpswa_interface; +EXPORT_SYMBOL(fpswa_interface); + +void __init +trap_init (void) +{ + if (ia64_boot_param->fpswa) + /* FPSWA fixup: make the interface pointer a kernel virtual address: */ + fpswa_interface = __va(ia64_boot_param->fpswa); +} + +int +die (const char *str, struct pt_regs *regs, long err) +{ + static struct { + spinlock_t lock; + u32 lock_owner; + int lock_owner_depth; + } die = { + .lock = __SPIN_LOCK_UNLOCKED(die.lock), + .lock_owner = -1, + .lock_owner_depth = 0 + }; + static int die_counter; + int cpu = get_cpu(); + + if (die.lock_owner != cpu) { + console_verbose(); + spin_lock_irq(&die.lock); + die.lock_owner = cpu; + die.lock_owner_depth = 0; + bust_spinlocks(1); + } + put_cpu(); + + if (++die.lock_owner_depth < 3) { + printk("%s[%d]: %s %ld [%d]\n", + current->comm, task_pid_nr(current), str, err, ++die_counter); + if (notify_die(DIE_OOPS, str, regs, err, 255, SIGSEGV) + != NOTIFY_STOP) + show_regs(regs); + else + regs = NULL; + } else + printk(KERN_ERR "Recursive die() failure, output suppressed\n"); + + bust_spinlocks(0); + die.lock_owner = -1; + add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); + spin_unlock_irq(&die.lock); + + if (!regs) + return 1; + + if (panic_on_oops) + panic("Fatal exception"); + + make_task_dead(SIGSEGV); + return 0; +} + +int +die_if_kernel (char *str, struct pt_regs *regs, long err) +{ + if (!user_mode(regs)) + return die(str, regs, err); + return 0; +} + +void +__kprobes ia64_bad_break (unsigned long break_num, struct pt_regs *regs) +{ + int sig, code; + + switch (break_num) { + case 0: /* unknown error (used by GCC for __builtin_abort()) */ + if (notify_die(DIE_BREAK, "break 0", regs, break_num, TRAP_BRKPT, SIGTRAP) + == NOTIFY_STOP) + return; + if (die_if_kernel("bugcheck!", regs, break_num)) + return; + sig = SIGILL; code = ILL_ILLOPC; + break; + + case 1: /* integer divide by zero */ + sig = SIGFPE; code = FPE_INTDIV; + break; + + case 2: /* integer overflow */ + sig = SIGFPE; code = FPE_INTOVF; + break; + + case 3: /* range check/bounds check */ + sig = SIGFPE; code = FPE_FLTSUB; + break; + + case 4: /* null pointer dereference */ + sig = SIGSEGV; code = SEGV_MAPERR; + break; + + case 5: /* misaligned data */ + sig = SIGSEGV; code = BUS_ADRALN; + break; + + case 6: /* decimal overflow */ + sig = SIGFPE; code = __FPE_DECOVF; + break; + + case 7: /* decimal divide by zero */ + sig = SIGFPE; code = __FPE_DECDIV; + break; + + case 8: /* packed decimal error */ + sig = SIGFPE; code = __FPE_DECERR; + break; + + case 9: /* invalid ASCII digit */ + sig = SIGFPE; code = __FPE_INVASC; + break; + + case 10: /* invalid decimal digit */ + sig = SIGFPE; code = __FPE_INVDEC; + break; + + case 11: /* paragraph stack overflow */ + sig = SIGSEGV; code = __SEGV_PSTKOVF; + break; + + case 0x3f000 ... 0x3ffff: /* bundle-update in progress */ + sig = SIGILL; code = __ILL_BNDMOD; + break; + + default: + if ((break_num < 0x40000 || break_num > 0x100000) + && die_if_kernel("Bad break", regs, break_num)) + return; + + if (break_num < 0x80000) { + sig = SIGILL; code = __ILL_BREAK; + } else { + if (notify_die(DIE_BREAK, "bad break", regs, break_num, TRAP_BRKPT, SIGTRAP) + == NOTIFY_STOP) + return; + sig = SIGTRAP; code = TRAP_BRKPT; + } + } + force_sig_fault(sig, code, + (void __user *) (regs->cr_iip + ia64_psr(regs)->ri), + break_num, 0 /* clear __ISR_VALID */, 0); +} + +/* + * disabled_fph_fault() is called when a user-level process attempts to access f32..f127 + * and it doesn't own the fp-high register partition. When this happens, we save the + * current fph partition in the task_struct of the fpu-owner (if necessary) and then load + * the fp-high partition of the current task (if necessary). Note that the kernel has + * access to fph by the time we get here, as the IVT's "Disabled FP-Register" handler takes + * care of clearing psr.dfh. + */ +static inline void +disabled_fph_fault (struct pt_regs *regs) +{ + struct ia64_psr *psr = ia64_psr(regs); + + /* first, grant user-level access to fph partition: */ + psr->dfh = 0; + + /* + * Make sure that no other task gets in on this processor + * while we're claiming the FPU + */ + preempt_disable(); +#ifndef CONFIG_SMP + { + struct task_struct *fpu_owner + = (struct task_struct *)ia64_get_kr(IA64_KR_FPU_OWNER); + + if (ia64_is_local_fpu_owner(current)) { + preempt_enable_no_resched(); + return; + } + + if (fpu_owner) + ia64_flush_fph(fpu_owner); + } +#endif /* !CONFIG_SMP */ + ia64_set_local_fpu_owner(current); + if ((current->thread.flags & IA64_THREAD_FPH_VALID) != 0) { + __ia64_load_fpu(current->thread.fph); + psr->mfh = 0; + } else { + __ia64_init_fpu(); + /* + * Set mfh because the state in thread.fph does not match the state in + * the fph partition. + */ + psr->mfh = 1; + } + preempt_enable_no_resched(); +} + +static inline int +fp_emulate (int fp_fault, void *bundle, long *ipsr, long *fpsr, long *isr, long *pr, long *ifs, + struct pt_regs *regs) +{ + fp_state_t fp_state; + fpswa_ret_t ret; + + if (!fpswa_interface) + return -1; + + memset(&fp_state, 0, sizeof(fp_state_t)); + + /* + * compute fp_state. only FP registers f6 - f11 are used by the + * kernel, so set those bits in the mask and set the low volatile + * pointer to point to these registers. + */ + fp_state.bitmask_low64 = 0xfc0; /* bit6..bit11 */ + + fp_state.fp_state_low_volatile = (fp_state_low_volatile_t *) ®s->f6; + /* + * unsigned long (*EFI_FPSWA) ( + * unsigned long trap_type, + * void *Bundle, + * unsigned long *pipsr, + * unsigned long *pfsr, + * unsigned long *pisr, + * unsigned long *ppreds, + * unsigned long *pifs, + * void *fp_state); + */ + ret = (*fpswa_interface->fpswa)((unsigned long) fp_fault, bundle, + (unsigned long *) ipsr, (unsigned long *) fpsr, + (unsigned long *) isr, (unsigned long *) pr, + (unsigned long *) ifs, &fp_state); + + return ret.status; +} + +struct fpu_swa_msg { + unsigned long count; + unsigned long time; +}; +static DEFINE_PER_CPU(struct fpu_swa_msg, cpulast); +DECLARE_PER_CPU(struct fpu_swa_msg, cpulast); +static struct fpu_swa_msg last __cacheline_aligned; + + +/* + * Handle floating-point assist faults and traps. + */ +static int +handle_fpu_swa (int fp_fault, struct pt_regs *regs, unsigned long isr) +{ + long exception, bundle[2]; + unsigned long fault_ip; + + fault_ip = regs->cr_iip; + if (!fp_fault && (ia64_psr(regs)->ri == 0)) + fault_ip -= 16; + if (copy_from_user(bundle, (void __user *) fault_ip, sizeof(bundle))) + return -1; + + if (!(current->thread.flags & IA64_THREAD_FPEMU_NOPRINT)) { + unsigned long count, current_jiffies = jiffies; + struct fpu_swa_msg *cp = this_cpu_ptr(&cpulast); + + if (unlikely(current_jiffies > cp->time)) + cp->count = 0; + if (unlikely(cp->count < 5)) { + cp->count++; + cp->time = current_jiffies + 5 * HZ; + + /* minimize races by grabbing a copy of count BEFORE checking last.time. */ + count = last.count; + barrier(); + + /* + * Lower 4 bits are used as a count. Upper bits are a sequence + * number that is updated when count is reset. The cmpxchg will + * fail is seqno has changed. This minimizes multiple cpus + * resetting the count. + */ + if (current_jiffies > last.time) + (void) cmpxchg_acq(&last.count, count, 16 + (count & ~15)); + + /* used fetchadd to atomically update the count */ + if ((last.count & 15) < 5 && (ia64_fetchadd(1, &last.count, acq) & 15) < 5) { + last.time = current_jiffies + 5 * HZ; + printk(KERN_WARNING + "%s(%d): floating-point assist fault at ip %016lx, isr %016lx\n", + current->comm, task_pid_nr(current), regs->cr_iip + ia64_psr(regs)->ri, isr); + } + } + } + + exception = fp_emulate(fp_fault, bundle, ®s->cr_ipsr, ®s->ar_fpsr, &isr, ®s->pr, + ®s->cr_ifs, regs); + if (fp_fault) { + if (exception == 0) { + /* emulation was successful */ + ia64_increment_ip(regs); + } else if (exception == -1) { + printk(KERN_ERR "handle_fpu_swa: fp_emulate() returned -1\n"); + return -1; + } else { + /* is next instruction a trap? */ + int si_code; + + if (exception & 2) { + ia64_increment_ip(regs); + } + si_code = FPE_FLTUNK; /* default code */ + if (isr & 0x11) { + si_code = FPE_FLTINV; + } else if (isr & 0x22) { + /* denormal operand gets the same si_code as underflow + * see arch/i386/kernel/traps.c:math_error() */ + si_code = FPE_FLTUND; + } else if (isr & 0x44) { + si_code = FPE_FLTDIV; + } + force_sig_fault(SIGFPE, si_code, + (void __user *) (regs->cr_iip + ia64_psr(regs)->ri), + 0, __ISR_VALID, isr); + } + } else { + if (exception == -1) { + printk(KERN_ERR "handle_fpu_swa: fp_emulate() returned -1\n"); + return -1; + } else if (exception != 0) { + /* raise exception */ + int si_code; + + si_code = FPE_FLTUNK; /* default code */ + if (isr & 0x880) { + si_code = FPE_FLTOVF; + } else if (isr & 0x1100) { + si_code = FPE_FLTUND; + } else if (isr & 0x2200) { + si_code = FPE_FLTRES; + } + force_sig_fault(SIGFPE, si_code, + (void __user *) (regs->cr_iip + ia64_psr(regs)->ri), + 0, __ISR_VALID, isr); + } + } + return 0; +} + +struct illegal_op_return { + unsigned long fkt, arg1, arg2, arg3; +}; + +struct illegal_op_return +ia64_illegal_op_fault (unsigned long ec, long arg1, long arg2, long arg3, + long arg4, long arg5, long arg6, long arg7, + struct pt_regs regs) +{ + struct illegal_op_return rv; + char buf[128]; + +#ifdef CONFIG_IA64_BRL_EMU + { + extern struct illegal_op_return ia64_emulate_brl (struct pt_regs *, unsigned long); + + rv = ia64_emulate_brl(®s, ec); + if (rv.fkt != (unsigned long) -1) + return rv; + } +#endif + + sprintf(buf, "IA-64 Illegal operation fault"); + rv.fkt = 0; + if (die_if_kernel(buf, ®s, 0)) + return rv; + + force_sig_fault(SIGILL, ILL_ILLOPC, + (void __user *) (regs.cr_iip + ia64_psr(®s)->ri), + 0, 0, 0); + return rv; +} + +void __kprobes +ia64_fault (unsigned long vector, unsigned long isr, unsigned long ifa, + unsigned long iim, unsigned long itir, long arg5, long arg6, + long arg7, struct pt_regs regs) +{ + unsigned long code, error = isr, iip; + char buf[128]; + int result, sig, si_code; + static const char *reason[] = { + "IA-64 Illegal Operation fault", + "IA-64 Privileged Operation fault", + "IA-64 Privileged Register fault", + "IA-64 Reserved Register/Field fault", + "Disabled Instruction Set Transition fault", + "Unknown fault 5", "Unknown fault 6", "Unknown fault 7", "Illegal Hazard fault", + "Unknown fault 9", "Unknown fault 10", "Unknown fault 11", "Unknown fault 12", + "Unknown fault 13", "Unknown fault 14", "Unknown fault 15" + }; + + if ((isr & IA64_ISR_NA) && ((isr & IA64_ISR_CODE_MASK) == IA64_ISR_CODE_LFETCH)) { + /* + * This fault was due to lfetch.fault, set "ed" bit in the psr to cancel + * the lfetch. + */ + ia64_psr(®s)->ed = 1; + return; + } + + iip = regs.cr_iip + ia64_psr(®s)->ri; + + switch (vector) { + case 24: /* General Exception */ + code = (isr >> 4) & 0xf; + sprintf(buf, "General Exception: %s%s", reason[code], + (code == 3) ? ((isr & (1UL << 37)) + ? " (RSE access)" : " (data access)") : ""); + if (code == 8) { +# ifdef CONFIG_IA64_PRINT_HAZARDS + printk("%s[%d]: possible hazard @ ip=%016lx (pr = %016lx)\n", + current->comm, task_pid_nr(current), + regs.cr_iip + ia64_psr(®s)->ri, regs.pr); +# endif + return; + } + break; + + case 25: /* Disabled FP-Register */ + if (isr & 2) { + disabled_fph_fault(®s); + return; + } + sprintf(buf, "Disabled FPL fault---not supposed to happen!"); + break; + + case 26: /* NaT Consumption */ + if (user_mode(®s)) { + void __user *addr; + + if (((isr >> 4) & 0xf) == 2) { + /* NaT page consumption */ + sig = SIGSEGV; + code = SEGV_ACCERR; + addr = (void __user *) ifa; + } else { + /* register NaT consumption */ + sig = SIGILL; + code = ILL_ILLOPN; + addr = (void __user *) (regs.cr_iip + + ia64_psr(®s)->ri); + } + force_sig_fault(sig, code, addr, + vector, __ISR_VALID, isr); + return; + } else if (ia64_done_with_exception(®s)) + return; + sprintf(buf, "NaT consumption"); + break; + + case 31: /* Unsupported Data Reference */ + if (user_mode(®s)) { + force_sig_fault(SIGILL, ILL_ILLOPN, (void __user *) iip, + vector, __ISR_VALID, isr); + return; + } + sprintf(buf, "Unsupported data reference"); + break; + + case 29: /* Debug */ + case 35: /* Taken Branch Trap */ + case 36: /* Single Step Trap */ + if (fsys_mode(current, ®s)) { + extern char __kernel_syscall_via_break[]; + /* + * Got a trap in fsys-mode: Taken Branch Trap + * and Single Step trap need special handling; + * Debug trap is ignored (we disable it here + * and re-enable it in the lower-privilege trap). + */ + if (unlikely(vector == 29)) { + set_thread_flag(TIF_DB_DISABLED); + ia64_psr(®s)->db = 0; + ia64_psr(®s)->lp = 1; + return; + } + /* re-do the system call via break 0x100000: */ + regs.cr_iip = (unsigned long) __kernel_syscall_via_break; + ia64_psr(®s)->ri = 0; + ia64_psr(®s)->cpl = 3; + return; + } + switch (vector) { + default: + case 29: + si_code = TRAP_HWBKPT; +#ifdef CONFIG_ITANIUM + /* + * Erratum 10 (IFA may contain incorrect address) now has + * "NoFix" status. There are no plans for fixing this. + */ + if (ia64_psr(®s)->is == 0) + ifa = regs.cr_iip; +#endif + break; + case 35: si_code = TRAP_BRANCH; ifa = 0; break; + case 36: si_code = TRAP_TRACE; ifa = 0; break; + } + if (notify_die(DIE_FAULT, "ia64_fault", ®s, vector, si_code, SIGTRAP) + == NOTIFY_STOP) + return; + force_sig_fault(SIGTRAP, si_code, (void __user *) ifa, + 0, __ISR_VALID, isr); + return; + + case 32: /* fp fault */ + case 33: /* fp trap */ + result = handle_fpu_swa((vector == 32) ? 1 : 0, ®s, isr); + if ((result < 0) || (current->thread.flags & IA64_THREAD_FPEMU_SIGFPE)) { + force_sig_fault(SIGFPE, FPE_FLTINV, (void __user *) iip, + 0, __ISR_VALID, isr); + } + return; + + case 34: + if (isr & 0x2) { + /* Lower-Privilege Transfer Trap */ + + /* If we disabled debug traps during an fsyscall, + * re-enable them here. + */ + if (test_thread_flag(TIF_DB_DISABLED)) { + clear_thread_flag(TIF_DB_DISABLED); + ia64_psr(®s)->db = 1; + } + + /* + * Just clear PSR.lp and then return immediately: + * all the interesting work (e.g., signal delivery) + * is done in the kernel exit path. + */ + ia64_psr(®s)->lp = 0; + return; + } else { + /* Unimplemented Instr. Address Trap */ + if (user_mode(®s)) { + force_sig_fault(SIGILL, ILL_BADIADDR, + (void __user *) iip, + 0, 0, 0); + return; + } + sprintf(buf, "Unimplemented Instruction Address fault"); + } + break; + + case 45: + printk(KERN_ERR "Unexpected IA-32 exception (Trap 45)\n"); + printk(KERN_ERR " iip - 0x%lx, ifa - 0x%lx, isr - 0x%lx\n", + iip, ifa, isr); + force_sig(SIGSEGV); + return; + + case 46: + printk(KERN_ERR "Unexpected IA-32 intercept trap (Trap 46)\n"); + printk(KERN_ERR " iip - 0x%lx, ifa - 0x%lx, isr - 0x%lx, iim - 0x%lx\n", + iip, ifa, isr, iim); + force_sig(SIGSEGV); + return; + + case 47: + sprintf(buf, "IA-32 Interruption Fault (int 0x%lx)", isr >> 16); + break; + + default: + sprintf(buf, "Fault %lu", vector); + break; + } + if (!die_if_kernel(buf, ®s, error)) + force_sig(SIGILL); +} |