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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/ia64/kernel/traps.c
Initial import
Diffstat (limited to 'arch/ia64/kernel/traps.c')
-rw-r--r--arch/ia64/kernel/traps.c652
1 files changed, 652 insertions, 0 deletions
diff --git a/arch/ia64/kernel/traps.c b/arch/ia64/kernel/traps.c
new file mode 100644
index 000000000..6f7d4a4dc
--- /dev/null
+++ b/arch/ia64/kernel/traps.c
@@ -0,0 +1,652 @@
+/*
+ * 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.h>
+#include <linux/tty.h>
+#include <linux/vt_kern.h> /* For unblank_screen() */
+#include <linux/module.h> /* for EXPORT_SYMBOL */
+#include <linux/hardirq.h>
+#include <linux/kprobes.h>
+#include <linux/delay.h> /* for ssleep() */
+#include <linux/kdebug.h>
+
+#include <asm/fpswa.h>
+#include <asm/intrinsics.h>
+#include <asm/processor.h>
+#include <asm/uaccess.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");
+
+ do_exit(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)
+{
+ siginfo_t siginfo;
+ int sig, code;
+
+ /* SIGILL, SIGFPE, SIGSEGV, and SIGBUS want these field initialized: */
+ siginfo.si_addr = (void __user *) (regs->cr_iip + ia64_psr(regs)->ri);
+ siginfo.si_imm = break_num;
+ siginfo.si_flags = 0; /* clear __ISR_VALID */
+ siginfo.si_isr = 0;
+
+ 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;
+ }
+ }
+ siginfo.si_signo = sig;
+ siginfo.si_errno = 0;
+ siginfo.si_code = code;
+ force_sig_info(sig, &siginfo, current);
+}
+
+/*
+ * 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 *) &regs->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;
+ struct siginfo siginfo;
+
+ 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 mutiple 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, &regs->cr_ipsr, &regs->ar_fpsr, &isr, &regs->pr,
+ &regs->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? */
+ if (exception & 2) {
+ ia64_increment_ip(regs);
+ }
+ siginfo.si_signo = SIGFPE;
+ siginfo.si_errno = 0;
+ siginfo.si_code = __SI_FAULT; /* default code */
+ siginfo.si_addr = (void __user *) (regs->cr_iip + ia64_psr(regs)->ri);
+ if (isr & 0x11) {
+ siginfo.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() */
+ siginfo.si_code = FPE_FLTUND;
+ } else if (isr & 0x44) {
+ siginfo.si_code = FPE_FLTDIV;
+ }
+ siginfo.si_isr = isr;
+ siginfo.si_flags = __ISR_VALID;
+ siginfo.si_imm = 0;
+ force_sig_info(SIGFPE, &siginfo, current);
+ }
+ } else {
+ if (exception == -1) {
+ printk(KERN_ERR "handle_fpu_swa: fp_emulate() returned -1\n");
+ return -1;
+ } else if (exception != 0) {
+ /* raise exception */
+ siginfo.si_signo = SIGFPE;
+ siginfo.si_errno = 0;
+ siginfo.si_code = __SI_FAULT; /* default code */
+ siginfo.si_addr = (void __user *) (regs->cr_iip + ia64_psr(regs)->ri);
+ if (isr & 0x880) {
+ siginfo.si_code = FPE_FLTOVF;
+ } else if (isr & 0x1100) {
+ siginfo.si_code = FPE_FLTUND;
+ } else if (isr & 0x2200) {
+ siginfo.si_code = FPE_FLTRES;
+ }
+ siginfo.si_isr = isr;
+ siginfo.si_flags = __ISR_VALID;
+ siginfo.si_imm = 0;
+ force_sig_info(SIGFPE, &siginfo, current);
+ }
+ }
+ 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;
+ struct siginfo si;
+ 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(&regs, 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, &regs, 0))
+ return rv;
+
+ memset(&si, 0, sizeof(si));
+ si.si_signo = SIGILL;
+ si.si_code = ILL_ILLOPC;
+ si.si_addr = (void __user *) (regs.cr_iip + ia64_psr(&regs)->ri);
+ force_sig_info(SIGILL, &si, current);
+ 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;
+ struct siginfo siginfo;
+ char buf[128];
+ int result, sig;
+ 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(&regs)->ed = 1;
+ return;
+ }
+
+ iip = regs.cr_iip + ia64_psr(&regs)->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(&regs)->ri, regs.pr);
+# endif
+ return;
+ }
+ break;
+
+ case 25: /* Disabled FP-Register */
+ if (isr & 2) {
+ disabled_fph_fault(&regs);
+ return;
+ }
+ sprintf(buf, "Disabled FPL fault---not supposed to happen!");
+ break;
+
+ case 26: /* NaT Consumption */
+ if (user_mode(&regs)) {
+ 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(&regs)->ri);
+ }
+ siginfo.si_signo = sig;
+ siginfo.si_code = code;
+ siginfo.si_errno = 0;
+ siginfo.si_addr = addr;
+ siginfo.si_imm = vector;
+ siginfo.si_flags = __ISR_VALID;
+ siginfo.si_isr = isr;
+ force_sig_info(sig, &siginfo, current);
+ return;
+ } else if (ia64_done_with_exception(&regs))
+ return;
+ sprintf(buf, "NaT consumption");
+ break;
+
+ case 31: /* Unsupported Data Reference */
+ if (user_mode(&regs)) {
+ siginfo.si_signo = SIGILL;
+ siginfo.si_code = ILL_ILLOPN;
+ siginfo.si_errno = 0;
+ siginfo.si_addr = (void __user *) iip;
+ siginfo.si_imm = vector;
+ siginfo.si_flags = __ISR_VALID;
+ siginfo.si_isr = isr;
+ force_sig_info(SIGILL, &siginfo, current);
+ return;
+ }
+ sprintf(buf, "Unsupported data reference");
+ break;
+
+ case 29: /* Debug */
+ case 35: /* Taken Branch Trap */
+ case 36: /* Single Step Trap */
+ if (fsys_mode(current, &regs)) {
+ 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(&regs)->db = 0;
+ ia64_psr(&regs)->lp = 1;
+ return;
+ }
+ /* re-do the system call via break 0x100000: */
+ regs.cr_iip = (unsigned long) __kernel_syscall_via_break;
+ ia64_psr(&regs)->ri = 0;
+ ia64_psr(&regs)->cpl = 3;
+ return;
+ }
+ switch (vector) {
+ case 29:
+ siginfo.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(&regs)->is == 0)
+ ifa = regs.cr_iip;
+#endif
+ break;
+ case 35: siginfo.si_code = TRAP_BRANCH; ifa = 0; break;
+ case 36: siginfo.si_code = TRAP_TRACE; ifa = 0; break;
+ }
+ if (notify_die(DIE_FAULT, "ia64_fault", &regs, vector, siginfo.si_code, SIGTRAP)
+ == NOTIFY_STOP)
+ return;
+ siginfo.si_signo = SIGTRAP;
+ siginfo.si_errno = 0;
+ siginfo.si_addr = (void __user *) ifa;
+ siginfo.si_imm = 0;
+ siginfo.si_flags = __ISR_VALID;
+ siginfo.si_isr = isr;
+ force_sig_info(SIGTRAP, &siginfo, current);
+ return;
+
+ case 32: /* fp fault */
+ case 33: /* fp trap */
+ result = handle_fpu_swa((vector == 32) ? 1 : 0, &regs, isr);
+ if ((result < 0) || (current->thread.flags & IA64_THREAD_FPEMU_SIGFPE)) {
+ siginfo.si_signo = SIGFPE;
+ siginfo.si_errno = 0;
+ siginfo.si_code = FPE_FLTINV;
+ siginfo.si_addr = (void __user *) iip;
+ siginfo.si_flags = __ISR_VALID;
+ siginfo.si_isr = isr;
+ siginfo.si_imm = 0;
+ force_sig_info(SIGFPE, &siginfo, current);
+ }
+ 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(&regs)->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(&regs)->lp = 0;
+ return;
+ } else {
+ /* Unimplemented Instr. Address Trap */
+ if (user_mode(&regs)) {
+ siginfo.si_signo = SIGILL;
+ siginfo.si_code = ILL_BADIADDR;
+ siginfo.si_errno = 0;
+ siginfo.si_flags = 0;
+ siginfo.si_isr = 0;
+ siginfo.si_imm = 0;
+ siginfo.si_addr = (void __user *) iip;
+ force_sig_info(SIGILL, &siginfo, current);
+ 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, current);
+ 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, current);
+ 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, &regs, error))
+ force_sig(SIGILL, current);
+}