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-rw-r--r--arch/powerpc/kernel/traps.c2330
1 files changed, 2330 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
new file mode 100644
index 0000000000..fe3f720c9c
--- /dev/null
+++ b/arch/powerpc/kernel/traps.c
@@ -0,0 +1,2330 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ * Copyright 2007-2010 Freescale Semiconductor, Inc.
+ *
+ * Modified by Cort Dougan (cort@cs.nmt.edu)
+ * and Paul Mackerras (paulus@samba.org)
+ */
+
+/*
+ * This file handles the architecture-dependent parts of hardware exceptions
+ */
+
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/pkeys.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/extable.h>
+#include <linux/module.h> /* print_modules */
+#include <linux/prctl.h>
+#include <linux/delay.h>
+#include <linux/kprobes.h>
+#include <linux/kexec.h>
+#include <linux/backlight.h>
+#include <linux/bug.h>
+#include <linux/kdebug.h>
+#include <linux/ratelimit.h>
+#include <linux/context_tracking.h>
+#include <linux/smp.h>
+#include <linux/console.h>
+#include <linux/kmsg_dump.h>
+#include <linux/debugfs.h>
+
+#include <asm/emulated_ops.h>
+#include <linux/uaccess.h>
+#include <asm/interrupt.h>
+#include <asm/io.h>
+#include <asm/machdep.h>
+#include <asm/rtas.h>
+#include <asm/pmc.h>
+#include <asm/reg.h>
+#ifdef CONFIG_PMAC_BACKLIGHT
+#include <asm/backlight.h>
+#endif
+#ifdef CONFIG_PPC64
+#include <asm/firmware.h>
+#include <asm/processor.h>
+#endif
+#include <asm/kexec.h>
+#include <asm/ppc-opcode.h>
+#include <asm/rio.h>
+#include <asm/fadump.h>
+#include <asm/switch_to.h>
+#include <asm/tm.h>
+#include <asm/debug.h>
+#include <asm/asm-prototypes.h>
+#include <asm/hmi.h>
+#include <sysdev/fsl_pci.h>
+#include <asm/kprobes.h>
+#include <asm/stacktrace.h>
+#include <asm/nmi.h>
+#include <asm/disassemble.h>
+#include <asm/udbg.h>
+
+#if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC_CORE)
+int (*__debugger)(struct pt_regs *regs) __read_mostly;
+int (*__debugger_ipi)(struct pt_regs *regs) __read_mostly;
+int (*__debugger_bpt)(struct pt_regs *regs) __read_mostly;
+int (*__debugger_sstep)(struct pt_regs *regs) __read_mostly;
+int (*__debugger_iabr_match)(struct pt_regs *regs) __read_mostly;
+int (*__debugger_break_match)(struct pt_regs *regs) __read_mostly;
+int (*__debugger_fault_handler)(struct pt_regs *regs) __read_mostly;
+
+EXPORT_SYMBOL(__debugger);
+EXPORT_SYMBOL(__debugger_ipi);
+EXPORT_SYMBOL(__debugger_bpt);
+EXPORT_SYMBOL(__debugger_sstep);
+EXPORT_SYMBOL(__debugger_iabr_match);
+EXPORT_SYMBOL(__debugger_break_match);
+EXPORT_SYMBOL(__debugger_fault_handler);
+#endif
+
+/* Transactional Memory trap debug */
+#ifdef TM_DEBUG_SW
+#define TM_DEBUG(x...) printk(KERN_INFO x)
+#else
+#define TM_DEBUG(x...) do { } while(0)
+#endif
+
+static const char *signame(int signr)
+{
+ switch (signr) {
+ case SIGBUS: return "bus error";
+ case SIGFPE: return "floating point exception";
+ case SIGILL: return "illegal instruction";
+ case SIGSEGV: return "segfault";
+ case SIGTRAP: return "unhandled trap";
+ }
+
+ return "unknown signal";
+}
+
+/*
+ * Trap & Exception support
+ */
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+static void pmac_backlight_unblank(void)
+{
+ mutex_lock(&pmac_backlight_mutex);
+ if (pmac_backlight) {
+ struct backlight_properties *props;
+
+ props = &pmac_backlight->props;
+ props->brightness = props->max_brightness;
+ props->power = FB_BLANK_UNBLANK;
+ backlight_update_status(pmac_backlight);
+ }
+ mutex_unlock(&pmac_backlight_mutex);
+}
+#else
+static inline void pmac_backlight_unblank(void) { }
+#endif
+
+/*
+ * If oops/die is expected to crash the machine, return true here.
+ *
+ * This should not be expected to be 100% accurate, there may be
+ * notifiers registered or other unexpected conditions that may bring
+ * down the kernel. Or if the current process in the kernel is holding
+ * locks or has other critical state, the kernel may become effectively
+ * unusable anyway.
+ */
+bool die_will_crash(void)
+{
+ if (should_fadump_crash())
+ return true;
+ if (kexec_should_crash(current))
+ return true;
+ if (in_interrupt() || panic_on_oops ||
+ !current->pid || is_global_init(current))
+ return true;
+
+ return false;
+}
+
+static arch_spinlock_t die_lock = __ARCH_SPIN_LOCK_UNLOCKED;
+static int die_owner = -1;
+static unsigned int die_nest_count;
+static int die_counter;
+
+extern void panic_flush_kmsg_start(void)
+{
+ /*
+ * These are mostly taken from kernel/panic.c, but tries to do
+ * relatively minimal work. Don't use delay functions (TB may
+ * be broken), don't crash dump (need to set a firmware log),
+ * don't run notifiers. We do want to get some information to
+ * Linux console.
+ */
+ console_verbose();
+ bust_spinlocks(1);
+}
+
+extern void panic_flush_kmsg_end(void)
+{
+ kmsg_dump(KMSG_DUMP_PANIC);
+ bust_spinlocks(0);
+ debug_locks_off();
+ console_flush_on_panic(CONSOLE_FLUSH_PENDING);
+}
+
+static unsigned long oops_begin(struct pt_regs *regs)
+{
+ int cpu;
+ unsigned long flags;
+
+ oops_enter();
+
+ /* racy, but better than risking deadlock. */
+ raw_local_irq_save(flags);
+ cpu = smp_processor_id();
+ if (!arch_spin_trylock(&die_lock)) {
+ if (cpu == die_owner)
+ /* nested oops. should stop eventually */;
+ else
+ arch_spin_lock(&die_lock);
+ }
+ die_nest_count++;
+ die_owner = cpu;
+ console_verbose();
+ bust_spinlocks(1);
+ if (machine_is(powermac))
+ pmac_backlight_unblank();
+ return flags;
+}
+NOKPROBE_SYMBOL(oops_begin);
+
+static void oops_end(unsigned long flags, struct pt_regs *regs,
+ int signr)
+{
+ bust_spinlocks(0);
+ add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
+ die_nest_count--;
+ oops_exit();
+ printk("\n");
+ if (!die_nest_count) {
+ /* Nest count reaches zero, release the lock. */
+ die_owner = -1;
+ arch_spin_unlock(&die_lock);
+ }
+ raw_local_irq_restore(flags);
+
+ /*
+ * system_reset_excption handles debugger, crash dump, panic, for 0x100
+ */
+ if (TRAP(regs) == INTERRUPT_SYSTEM_RESET)
+ return;
+
+ crash_fadump(regs, "die oops");
+
+ if (kexec_should_crash(current))
+ crash_kexec(regs);
+
+ if (!signr)
+ return;
+
+ /*
+ * While our oops output is serialised by a spinlock, output
+ * from panic() called below can race and corrupt it. If we
+ * know we are going to panic, delay for 1 second so we have a
+ * chance to get clean backtraces from all CPUs that are oopsing.
+ */
+ if (in_interrupt() || panic_on_oops || !current->pid ||
+ is_global_init(current)) {
+ mdelay(MSEC_PER_SEC);
+ }
+
+ if (panic_on_oops)
+ panic("Fatal exception");
+ make_task_dead(signr);
+}
+NOKPROBE_SYMBOL(oops_end);
+
+static char *get_mmu_str(void)
+{
+ if (early_radix_enabled())
+ return " MMU=Radix";
+ if (early_mmu_has_feature(MMU_FTR_HPTE_TABLE))
+ return " MMU=Hash";
+ return "";
+}
+
+static int __die(const char *str, struct pt_regs *regs, long err)
+{
+ printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
+
+ printk("%s PAGE_SIZE=%luK%s%s%s%s%s%s %s\n",
+ IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN) ? "LE" : "BE",
+ PAGE_SIZE / 1024, get_mmu_str(),
+ IS_ENABLED(CONFIG_PREEMPT) ? " PREEMPT" : "",
+ IS_ENABLED(CONFIG_SMP) ? " SMP" : "",
+ IS_ENABLED(CONFIG_SMP) ? (" NR_CPUS=" __stringify(NR_CPUS)) : "",
+ debug_pagealloc_enabled() ? " DEBUG_PAGEALLOC" : "",
+ IS_ENABLED(CONFIG_NUMA) ? " NUMA" : "",
+ ppc_md.name ? ppc_md.name : "");
+
+ if (notify_die(DIE_OOPS, str, regs, err, 255, SIGSEGV) == NOTIFY_STOP)
+ return 1;
+
+ print_modules();
+ show_regs(regs);
+
+ return 0;
+}
+NOKPROBE_SYMBOL(__die);
+
+void die(const char *str, struct pt_regs *regs, long err)
+{
+ unsigned long flags;
+
+ /*
+ * system_reset_excption handles debugger, crash dump, panic, for 0x100
+ */
+ if (TRAP(regs) != INTERRUPT_SYSTEM_RESET) {
+ if (debugger(regs))
+ return;
+ }
+
+ flags = oops_begin(regs);
+ if (__die(str, regs, err))
+ err = 0;
+ oops_end(flags, regs, err);
+}
+NOKPROBE_SYMBOL(die);
+
+void user_single_step_report(struct pt_regs *regs)
+{
+ force_sig_fault(SIGTRAP, TRAP_TRACE, (void __user *)regs->nip);
+}
+
+static void show_signal_msg(int signr, struct pt_regs *regs, int code,
+ unsigned long addr)
+{
+ static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL,
+ DEFAULT_RATELIMIT_BURST);
+
+ if (!show_unhandled_signals)
+ return;
+
+ if (!unhandled_signal(current, signr))
+ return;
+
+ if (!__ratelimit(&rs))
+ return;
+
+ pr_info("%s[%d]: %s (%d) at %lx nip %lx lr %lx code %x",
+ current->comm, current->pid, signame(signr), signr,
+ addr, regs->nip, regs->link, code);
+
+ print_vma_addr(KERN_CONT " in ", regs->nip);
+
+ pr_cont("\n");
+
+ show_user_instructions(regs);
+}
+
+static bool exception_common(int signr, struct pt_regs *regs, int code,
+ unsigned long addr)
+{
+ if (!user_mode(regs)) {
+ die("Exception in kernel mode", regs, signr);
+ return false;
+ }
+
+ /*
+ * Must not enable interrupts even for user-mode exception, because
+ * this can be called from machine check, which may be a NMI or IRQ
+ * which don't like interrupts being enabled. Could check for
+ * in_hardirq || in_nmi perhaps, but there doesn't seem to be a good
+ * reason why _exception() should enable irqs for an exception handler,
+ * the handlers themselves do that directly.
+ */
+
+ show_signal_msg(signr, regs, code, addr);
+
+ current->thread.trap_nr = code;
+
+ return true;
+}
+
+void _exception_pkey(struct pt_regs *regs, unsigned long addr, int key)
+{
+ if (!exception_common(SIGSEGV, regs, SEGV_PKUERR, addr))
+ return;
+
+ force_sig_pkuerr((void __user *) addr, key);
+}
+
+void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
+{
+ if (!exception_common(signr, regs, code, addr))
+ return;
+
+ force_sig_fault(signr, code, (void __user *)addr);
+}
+
+/*
+ * The interrupt architecture has a quirk in that the HV interrupts excluding
+ * the NMIs (0x100 and 0x200) do not clear MSR[RI] at entry. The first thing
+ * that an interrupt handler must do is save off a GPR into a scratch register,
+ * and all interrupts on POWERNV (HV=1) use the HSPRG1 register as scratch.
+ * Therefore an NMI can clobber an HV interrupt's live HSPRG1 without noticing
+ * that it is non-reentrant, which leads to random data corruption.
+ *
+ * The solution is for NMI interrupts in HV mode to check if they originated
+ * from these critical HV interrupt regions. If so, then mark them not
+ * recoverable.
+ *
+ * An alternative would be for HV NMIs to use SPRG for scratch to avoid the
+ * HSPRG1 clobber, however this would cause guest SPRG to be clobbered. Linux
+ * guests should always have MSR[RI]=0 when its scratch SPRG is in use, so
+ * that would work. However any other guest OS that may have the SPRG live
+ * and MSR[RI]=1 could encounter silent corruption.
+ *
+ * Builds that do not support KVM could take this second option to increase
+ * the recoverability of NMIs.
+ */
+noinstr void hv_nmi_check_nonrecoverable(struct pt_regs *regs)
+{
+#ifdef CONFIG_PPC_POWERNV
+ unsigned long kbase = (unsigned long)_stext;
+ unsigned long nip = regs->nip;
+
+ if (!(regs->msr & MSR_RI))
+ return;
+ if (!(regs->msr & MSR_HV))
+ return;
+ if (regs->msr & MSR_PR)
+ return;
+
+ /*
+ * Now test if the interrupt has hit a range that may be using
+ * HSPRG1 without having RI=0 (i.e., an HSRR interrupt). The
+ * problem ranges all run un-relocated. Test real and virt modes
+ * at the same time by dropping the high bit of the nip (virt mode
+ * entry points still have the +0x4000 offset).
+ */
+ nip &= ~0xc000000000000000ULL;
+ if ((nip >= 0x500 && nip < 0x600) || (nip >= 0x4500 && nip < 0x4600))
+ goto nonrecoverable;
+ if ((nip >= 0x980 && nip < 0xa00) || (nip >= 0x4980 && nip < 0x4a00))
+ goto nonrecoverable;
+ if ((nip >= 0xe00 && nip < 0xec0) || (nip >= 0x4e00 && nip < 0x4ec0))
+ goto nonrecoverable;
+ if ((nip >= 0xf80 && nip < 0xfa0) || (nip >= 0x4f80 && nip < 0x4fa0))
+ goto nonrecoverable;
+
+ /* Trampoline code runs un-relocated so subtract kbase. */
+ if (nip >= (unsigned long)(start_real_trampolines - kbase) &&
+ nip < (unsigned long)(end_real_trampolines - kbase))
+ goto nonrecoverable;
+ if (nip >= (unsigned long)(start_virt_trampolines - kbase) &&
+ nip < (unsigned long)(end_virt_trampolines - kbase))
+ goto nonrecoverable;
+ return;
+
+nonrecoverable:
+ regs->msr &= ~MSR_RI;
+ local_paca->hsrr_valid = 0;
+ local_paca->srr_valid = 0;
+#endif
+}
+DEFINE_INTERRUPT_HANDLER_NMI(system_reset_exception)
+{
+ unsigned long hsrr0, hsrr1;
+ bool saved_hsrrs = false;
+
+ /*
+ * System reset can interrupt code where HSRRs are live and MSR[RI]=1.
+ * The system reset interrupt itself may clobber HSRRs (e.g., to call
+ * OPAL), so save them here and restore them before returning.
+ *
+ * Machine checks don't need to save HSRRs, as the real mode handler
+ * is careful to avoid them, and the regular handler is not delivered
+ * as an NMI.
+ */
+ if (cpu_has_feature(CPU_FTR_HVMODE)) {
+ hsrr0 = mfspr(SPRN_HSRR0);
+ hsrr1 = mfspr(SPRN_HSRR1);
+ saved_hsrrs = true;
+ }
+
+ hv_nmi_check_nonrecoverable(regs);
+
+ __this_cpu_inc(irq_stat.sreset_irqs);
+
+ /* See if any machine dependent calls */
+ if (ppc_md.system_reset_exception) {
+ if (ppc_md.system_reset_exception(regs))
+ goto out;
+ }
+
+ if (debugger(regs))
+ goto out;
+
+ kmsg_dump(KMSG_DUMP_OOPS);
+ /*
+ * A system reset is a request to dump, so we always send
+ * it through the crashdump code (if fadump or kdump are
+ * registered).
+ */
+ crash_fadump(regs, "System Reset");
+
+ crash_kexec(regs);
+
+ /*
+ * We aren't the primary crash CPU. We need to send it
+ * to a holding pattern to avoid it ending up in the panic
+ * code.
+ */
+ crash_kexec_secondary(regs);
+
+ /*
+ * No debugger or crash dump registered, print logs then
+ * panic.
+ */
+ die("System Reset", regs, SIGABRT);
+
+ mdelay(2*MSEC_PER_SEC); /* Wait a little while for others to print */
+ add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
+ nmi_panic(regs, "System Reset");
+
+out:
+#ifdef CONFIG_PPC_BOOK3S_64
+ BUG_ON(get_paca()->in_nmi == 0);
+ if (get_paca()->in_nmi > 1)
+ die("Unrecoverable nested System Reset", regs, SIGABRT);
+#endif
+ /* Must die if the interrupt is not recoverable */
+ if (regs_is_unrecoverable(regs)) {
+ /* For the reason explained in die_mce, nmi_exit before die */
+ nmi_exit();
+ die("Unrecoverable System Reset", regs, SIGABRT);
+ }
+
+ if (saved_hsrrs) {
+ mtspr(SPRN_HSRR0, hsrr0);
+ mtspr(SPRN_HSRR1, hsrr1);
+ }
+
+ /* What should we do here? We could issue a shutdown or hard reset. */
+
+ return 0;
+}
+
+/*
+ * I/O accesses can cause machine checks on powermacs.
+ * Check if the NIP corresponds to the address of a sync
+ * instruction for which there is an entry in the exception
+ * table.
+ * -- paulus.
+ */
+static inline int check_io_access(struct pt_regs *regs)
+{
+#ifdef CONFIG_PPC32
+ unsigned long msr = regs->msr;
+ const struct exception_table_entry *entry;
+ unsigned int *nip = (unsigned int *)regs->nip;
+
+ if (((msr & 0xffff0000) == 0 || (msr & (0x80000 | 0x40000)))
+ && (entry = search_exception_tables(regs->nip)) != NULL) {
+ /*
+ * Check that it's a sync instruction, or somewhere
+ * in the twi; isync; nop sequence that inb/inw/inl uses.
+ * As the address is in the exception table
+ * we should be able to read the instr there.
+ * For the debug message, we look at the preceding
+ * load or store.
+ */
+ if (*nip == PPC_RAW_NOP())
+ nip -= 2;
+ else if (*nip == PPC_RAW_ISYNC())
+ --nip;
+ if (*nip == PPC_RAW_SYNC() || get_op(*nip) == OP_TRAP) {
+ unsigned int rb;
+
+ --nip;
+ rb = (*nip >> 11) & 0x1f;
+ printk(KERN_DEBUG "%s bad port %lx at %p\n",
+ (*nip & 0x100)? "OUT to": "IN from",
+ regs->gpr[rb] - _IO_BASE, nip);
+ regs_set_recoverable(regs);
+ regs_set_return_ip(regs, extable_fixup(entry));
+ return 1;
+ }
+ }
+#endif /* CONFIG_PPC32 */
+ return 0;
+}
+
+#ifdef CONFIG_PPC_ADV_DEBUG_REGS
+/* On 4xx, the reason for the machine check or program exception
+ is in the ESR. */
+#define get_reason(regs) ((regs)->esr)
+#define REASON_FP ESR_FP
+#define REASON_ILLEGAL (ESR_PIL | ESR_PUO)
+#define REASON_PRIVILEGED ESR_PPR
+#define REASON_TRAP ESR_PTR
+#define REASON_PREFIXED 0
+#define REASON_BOUNDARY 0
+
+/* single-step stuff */
+#define single_stepping(regs) (current->thread.debug.dbcr0 & DBCR0_IC)
+#define clear_single_step(regs) (current->thread.debug.dbcr0 &= ~DBCR0_IC)
+#define clear_br_trace(regs) do {} while(0)
+#else
+/* On non-4xx, the reason for the machine check or program
+ exception is in the MSR. */
+#define get_reason(regs) ((regs)->msr)
+#define REASON_TM SRR1_PROGTM
+#define REASON_FP SRR1_PROGFPE
+#define REASON_ILLEGAL SRR1_PROGILL
+#define REASON_PRIVILEGED SRR1_PROGPRIV
+#define REASON_TRAP SRR1_PROGTRAP
+#define REASON_PREFIXED SRR1_PREFIXED
+#define REASON_BOUNDARY SRR1_BOUNDARY
+
+#define single_stepping(regs) ((regs)->msr & MSR_SE)
+#define clear_single_step(regs) (regs_set_return_msr((regs), (regs)->msr & ~MSR_SE))
+#define clear_br_trace(regs) (regs_set_return_msr((regs), (regs)->msr & ~MSR_BE))
+#endif
+
+#define inst_length(reason) (((reason) & REASON_PREFIXED) ? 8 : 4)
+
+#if defined(CONFIG_PPC_E500)
+int machine_check_e500mc(struct pt_regs *regs)
+{
+ unsigned long mcsr = mfspr(SPRN_MCSR);
+ unsigned long pvr = mfspr(SPRN_PVR);
+ unsigned long reason = mcsr;
+ int recoverable = 1;
+
+ if (reason & MCSR_LD) {
+ recoverable = fsl_rio_mcheck_exception(regs);
+ if (recoverable == 1)
+ goto silent_out;
+ }
+
+ printk("Machine check in kernel mode.\n");
+ printk("Caused by (from MCSR=%lx): ", reason);
+
+ if (reason & MCSR_MCP)
+ pr_cont("Machine Check Signal\n");
+
+ if (reason & MCSR_ICPERR) {
+ pr_cont("Instruction Cache Parity Error\n");
+
+ /*
+ * This is recoverable by invalidating the i-cache.
+ */
+ mtspr(SPRN_L1CSR1, mfspr(SPRN_L1CSR1) | L1CSR1_ICFI);
+ while (mfspr(SPRN_L1CSR1) & L1CSR1_ICFI)
+ ;
+
+ /*
+ * This will generally be accompanied by an instruction
+ * fetch error report -- only treat MCSR_IF as fatal
+ * if it wasn't due to an L1 parity error.
+ */
+ reason &= ~MCSR_IF;
+ }
+
+ if (reason & MCSR_DCPERR_MC) {
+ pr_cont("Data Cache Parity Error\n");
+
+ /*
+ * In write shadow mode we auto-recover from the error, but it
+ * may still get logged and cause a machine check. We should
+ * only treat the non-write shadow case as non-recoverable.
+ */
+ /* On e6500 core, L1 DCWS (Data cache write shadow mode) bit
+ * is not implemented but L1 data cache always runs in write
+ * shadow mode. Hence on data cache parity errors HW will
+ * automatically invalidate the L1 Data Cache.
+ */
+ if (PVR_VER(pvr) != PVR_VER_E6500) {
+ if (!(mfspr(SPRN_L1CSR2) & L1CSR2_DCWS))
+ recoverable = 0;
+ }
+ }
+
+ if (reason & MCSR_L2MMU_MHIT) {
+ pr_cont("Hit on multiple TLB entries\n");
+ recoverable = 0;
+ }
+
+ if (reason & MCSR_NMI)
+ pr_cont("Non-maskable interrupt\n");
+
+ if (reason & MCSR_IF) {
+ pr_cont("Instruction Fetch Error Report\n");
+ recoverable = 0;
+ }
+
+ if (reason & MCSR_LD) {
+ pr_cont("Load Error Report\n");
+ recoverable = 0;
+ }
+
+ if (reason & MCSR_ST) {
+ pr_cont("Store Error Report\n");
+ recoverable = 0;
+ }
+
+ if (reason & MCSR_LDG) {
+ pr_cont("Guarded Load Error Report\n");
+ recoverable = 0;
+ }
+
+ if (reason & MCSR_TLBSYNC)
+ pr_cont("Simultaneous tlbsync operations\n");
+
+ if (reason & MCSR_BSL2_ERR) {
+ pr_cont("Level 2 Cache Error\n");
+ recoverable = 0;
+ }
+
+ if (reason & MCSR_MAV) {
+ u64 addr;
+
+ addr = mfspr(SPRN_MCAR);
+ addr |= (u64)mfspr(SPRN_MCARU) << 32;
+
+ pr_cont("Machine Check %s Address: %#llx\n",
+ reason & MCSR_MEA ? "Effective" : "Physical", addr);
+ }
+
+silent_out:
+ mtspr(SPRN_MCSR, mcsr);
+ return mfspr(SPRN_MCSR) == 0 && recoverable;
+}
+
+int machine_check_e500(struct pt_regs *regs)
+{
+ unsigned long reason = mfspr(SPRN_MCSR);
+
+ if (reason & MCSR_BUS_RBERR) {
+ if (fsl_rio_mcheck_exception(regs))
+ return 1;
+ if (fsl_pci_mcheck_exception(regs))
+ return 1;
+ }
+
+ printk("Machine check in kernel mode.\n");
+ printk("Caused by (from MCSR=%lx): ", reason);
+
+ if (reason & MCSR_MCP)
+ pr_cont("Machine Check Signal\n");
+ if (reason & MCSR_ICPERR)
+ pr_cont("Instruction Cache Parity Error\n");
+ if (reason & MCSR_DCP_PERR)
+ pr_cont("Data Cache Push Parity Error\n");
+ if (reason & MCSR_DCPERR)
+ pr_cont("Data Cache Parity Error\n");
+ if (reason & MCSR_BUS_IAERR)
+ pr_cont("Bus - Instruction Address Error\n");
+ if (reason & MCSR_BUS_RAERR)
+ pr_cont("Bus - Read Address Error\n");
+ if (reason & MCSR_BUS_WAERR)
+ pr_cont("Bus - Write Address Error\n");
+ if (reason & MCSR_BUS_IBERR)
+ pr_cont("Bus - Instruction Data Error\n");
+ if (reason & MCSR_BUS_RBERR)
+ pr_cont("Bus - Read Data Bus Error\n");
+ if (reason & MCSR_BUS_WBERR)
+ pr_cont("Bus - Write Data Bus Error\n");
+ if (reason & MCSR_BUS_IPERR)
+ pr_cont("Bus - Instruction Parity Error\n");
+ if (reason & MCSR_BUS_RPERR)
+ pr_cont("Bus - Read Parity Error\n");
+
+ return 0;
+}
+
+int machine_check_generic(struct pt_regs *regs)
+{
+ return 0;
+}
+#elif defined(CONFIG_PPC32)
+int machine_check_generic(struct pt_regs *regs)
+{
+ unsigned long reason = regs->msr;
+
+ printk("Machine check in kernel mode.\n");
+ printk("Caused by (from SRR1=%lx): ", reason);
+ switch (reason & 0x601F0000) {
+ case 0x80000:
+ pr_cont("Machine check signal\n");
+ break;
+ case 0x40000:
+ case 0x140000: /* 7450 MSS error and TEA */
+ pr_cont("Transfer error ack signal\n");
+ break;
+ case 0x20000:
+ pr_cont("Data parity error signal\n");
+ break;
+ case 0x10000:
+ pr_cont("Address parity error signal\n");
+ break;
+ case 0x20000000:
+ pr_cont("L1 Data Cache error\n");
+ break;
+ case 0x40000000:
+ pr_cont("L1 Instruction Cache error\n");
+ break;
+ case 0x00100000:
+ pr_cont("L2 data cache parity error\n");
+ break;
+ default:
+ pr_cont("Unknown values in msr\n");
+ }
+ return 0;
+}
+#endif /* everything else */
+
+void die_mce(const char *str, struct pt_regs *regs, long err)
+{
+ /*
+ * The machine check wants to kill the interrupted context,
+ * but make_task_dead() checks for in_interrupt() and panics
+ * in that case, so exit the irq/nmi before calling die.
+ */
+ if (in_nmi())
+ nmi_exit();
+ else
+ irq_exit();
+ die(str, regs, err);
+}
+
+/*
+ * BOOK3S_64 does not usually call this handler as a non-maskable interrupt
+ * (it uses its own early real-mode handler to handle the MCE proper
+ * and then raises irq_work to call this handler when interrupts are
+ * enabled). The only time when this is not true is if the early handler
+ * is unrecoverable, then it does call this directly to try to get a
+ * message out.
+ */
+static void __machine_check_exception(struct pt_regs *regs)
+{
+ int recover = 0;
+
+ __this_cpu_inc(irq_stat.mce_exceptions);
+
+ add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE);
+
+ /* See if any machine dependent calls. In theory, we would want
+ * to call the CPU first, and call the ppc_md. one if the CPU
+ * one returns a positive number. However there is existing code
+ * that assumes the board gets a first chance, so let's keep it
+ * that way for now and fix things later. --BenH.
+ */
+ if (ppc_md.machine_check_exception)
+ recover = ppc_md.machine_check_exception(regs);
+ else if (cur_cpu_spec->machine_check)
+ recover = cur_cpu_spec->machine_check(regs);
+
+ if (recover > 0)
+ goto bail;
+
+ if (debugger_fault_handler(regs))
+ goto bail;
+
+ if (check_io_access(regs))
+ goto bail;
+
+ die_mce("Machine check", regs, SIGBUS);
+
+bail:
+ /* Must die if the interrupt is not recoverable */
+ if (regs_is_unrecoverable(regs))
+ die_mce("Unrecoverable Machine check", regs, SIGBUS);
+}
+
+#ifdef CONFIG_PPC_BOOK3S_64
+DEFINE_INTERRUPT_HANDLER_RAW(machine_check_early_boot)
+{
+ udbg_printf("Machine check (early boot)\n");
+ udbg_printf("SRR0=0x%016lx SRR1=0x%016lx\n", regs->nip, regs->msr);
+ udbg_printf(" DAR=0x%016lx DSISR=0x%08lx\n", regs->dar, regs->dsisr);
+ udbg_printf(" LR=0x%016lx R1=0x%08lx\n", regs->link, regs->gpr[1]);
+ udbg_printf("------\n");
+ die("Machine check (early boot)", regs, SIGBUS);
+ for (;;)
+ ;
+ return 0;
+}
+
+DEFINE_INTERRUPT_HANDLER_ASYNC(machine_check_exception_async)
+{
+ __machine_check_exception(regs);
+}
+#endif
+DEFINE_INTERRUPT_HANDLER_NMI(machine_check_exception)
+{
+ __machine_check_exception(regs);
+
+ return 0;
+}
+
+DEFINE_INTERRUPT_HANDLER(SMIException) /* async? */
+{
+ die("System Management Interrupt", regs, SIGABRT);
+}
+
+#ifdef CONFIG_VSX
+static void p9_hmi_special_emu(struct pt_regs *regs)
+{
+ unsigned int ra, rb, t, i, sel, instr, rc;
+ const void __user *addr;
+ u8 vbuf[16] __aligned(16), *vdst;
+ unsigned long ea, msr, msr_mask;
+ bool swap;
+
+ if (__get_user(instr, (unsigned int __user *)regs->nip))
+ return;
+
+ /*
+ * lxvb16x opcode: 0x7c0006d8
+ * lxvd2x opcode: 0x7c000698
+ * lxvh8x opcode: 0x7c000658
+ * lxvw4x opcode: 0x7c000618
+ */
+ if ((instr & 0xfc00073e) != 0x7c000618) {
+ pr_devel("HMI vec emu: not vector CI %i:%s[%d] nip=%016lx"
+ " instr=%08x\n",
+ smp_processor_id(), current->comm, current->pid,
+ regs->nip, instr);
+ return;
+ }
+
+ /* Grab vector registers into the task struct */
+ msr = regs->msr; /* Grab msr before we flush the bits */
+ flush_vsx_to_thread(current);
+ enable_kernel_altivec();
+
+ /*
+ * Is userspace running with a different endian (this is rare but
+ * not impossible)
+ */
+ swap = (msr & MSR_LE) != (MSR_KERNEL & MSR_LE);
+
+ /* Decode the instruction */
+ ra = (instr >> 16) & 0x1f;
+ rb = (instr >> 11) & 0x1f;
+ t = (instr >> 21) & 0x1f;
+ if (instr & 1)
+ vdst = (u8 *)&current->thread.vr_state.vr[t];
+ else
+ vdst = (u8 *)&current->thread.fp_state.fpr[t][0];
+
+ /* Grab the vector address */
+ ea = regs->gpr[rb] + (ra ? regs->gpr[ra] : 0);
+ if (is_32bit_task())
+ ea &= 0xfffffffful;
+ addr = (__force const void __user *)ea;
+
+ /* Check it */
+ if (!access_ok(addr, 16)) {
+ pr_devel("HMI vec emu: bad access %i:%s[%d] nip=%016lx"
+ " instr=%08x addr=%016lx\n",
+ smp_processor_id(), current->comm, current->pid,
+ regs->nip, instr, (unsigned long)addr);
+ return;
+ }
+
+ /* Read the vector */
+ rc = 0;
+ if ((unsigned long)addr & 0xfUL)
+ /* unaligned case */
+ rc = __copy_from_user_inatomic(vbuf, addr, 16);
+ else
+ __get_user_atomic_128_aligned(vbuf, addr, rc);
+ if (rc) {
+ pr_devel("HMI vec emu: page fault %i:%s[%d] nip=%016lx"
+ " instr=%08x addr=%016lx\n",
+ smp_processor_id(), current->comm, current->pid,
+ regs->nip, instr, (unsigned long)addr);
+ return;
+ }
+
+ pr_devel("HMI vec emu: emulated vector CI %i:%s[%d] nip=%016lx"
+ " instr=%08x addr=%016lx\n",
+ smp_processor_id(), current->comm, current->pid, regs->nip,
+ instr, (unsigned long) addr);
+
+ /* Grab instruction "selector" */
+ sel = (instr >> 6) & 3;
+
+ /*
+ * Check to make sure the facility is actually enabled. This
+ * could happen if we get a false positive hit.
+ *
+ * lxvd2x/lxvw4x always check MSR VSX sel = 0,2
+ * lxvh8x/lxvb16x check MSR VSX or VEC depending on VSR used sel = 1,3
+ */
+ msr_mask = MSR_VSX;
+ if ((sel & 1) && (instr & 1)) /* lxvh8x & lxvb16x + VSR >= 32 */
+ msr_mask = MSR_VEC;
+ if (!(msr & msr_mask)) {
+ pr_devel("HMI vec emu: MSR fac clear %i:%s[%d] nip=%016lx"
+ " instr=%08x msr:%016lx\n",
+ smp_processor_id(), current->comm, current->pid,
+ regs->nip, instr, msr);
+ return;
+ }
+
+ /* Do logging here before we modify sel based on endian */
+ switch (sel) {
+ case 0: /* lxvw4x */
+ PPC_WARN_EMULATED(lxvw4x, regs);
+ break;
+ case 1: /* lxvh8x */
+ PPC_WARN_EMULATED(lxvh8x, regs);
+ break;
+ case 2: /* lxvd2x */
+ PPC_WARN_EMULATED(lxvd2x, regs);
+ break;
+ case 3: /* lxvb16x */
+ PPC_WARN_EMULATED(lxvb16x, regs);
+ break;
+ }
+
+#ifdef __LITTLE_ENDIAN__
+ /*
+ * An LE kernel stores the vector in the task struct as an LE
+ * byte array (effectively swapping both the components and
+ * the content of the components). Those instructions expect
+ * the components to remain in ascending address order, so we
+ * swap them back.
+ *
+ * If we are running a BE user space, the expectation is that
+ * of a simple memcpy, so forcing the emulation to look like
+ * a lxvb16x should do the trick.
+ */
+ if (swap)
+ sel = 3;
+
+ switch (sel) {
+ case 0: /* lxvw4x */
+ for (i = 0; i < 4; i++)
+ ((u32 *)vdst)[i] = ((u32 *)vbuf)[3-i];
+ break;
+ case 1: /* lxvh8x */
+ for (i = 0; i < 8; i++)
+ ((u16 *)vdst)[i] = ((u16 *)vbuf)[7-i];
+ break;
+ case 2: /* lxvd2x */
+ for (i = 0; i < 2; i++)
+ ((u64 *)vdst)[i] = ((u64 *)vbuf)[1-i];
+ break;
+ case 3: /* lxvb16x */
+ for (i = 0; i < 16; i++)
+ vdst[i] = vbuf[15-i];
+ break;
+ }
+#else /* __LITTLE_ENDIAN__ */
+ /* On a big endian kernel, a BE userspace only needs a memcpy */
+ if (!swap)
+ sel = 3;
+
+ /* Otherwise, we need to swap the content of the components */
+ switch (sel) {
+ case 0: /* lxvw4x */
+ for (i = 0; i < 4; i++)
+ ((u32 *)vdst)[i] = cpu_to_le32(((u32 *)vbuf)[i]);
+ break;
+ case 1: /* lxvh8x */
+ for (i = 0; i < 8; i++)
+ ((u16 *)vdst)[i] = cpu_to_le16(((u16 *)vbuf)[i]);
+ break;
+ case 2: /* lxvd2x */
+ for (i = 0; i < 2; i++)
+ ((u64 *)vdst)[i] = cpu_to_le64(((u64 *)vbuf)[i]);
+ break;
+ case 3: /* lxvb16x */
+ memcpy(vdst, vbuf, 16);
+ break;
+ }
+#endif /* !__LITTLE_ENDIAN__ */
+
+ /* Go to next instruction */
+ regs_add_return_ip(regs, 4);
+}
+#endif /* CONFIG_VSX */
+
+DEFINE_INTERRUPT_HANDLER_ASYNC(handle_hmi_exception)
+{
+ struct pt_regs *old_regs;
+
+ old_regs = set_irq_regs(regs);
+
+#ifdef CONFIG_VSX
+ /* Real mode flagged P9 special emu is needed */
+ if (local_paca->hmi_p9_special_emu) {
+ local_paca->hmi_p9_special_emu = 0;
+
+ /*
+ * We don't want to take page faults while doing the
+ * emulation, we just replay the instruction if necessary.
+ */
+ pagefault_disable();
+ p9_hmi_special_emu(regs);
+ pagefault_enable();
+ }
+#endif /* CONFIG_VSX */
+
+ if (ppc_md.handle_hmi_exception)
+ ppc_md.handle_hmi_exception(regs);
+
+ set_irq_regs(old_regs);
+}
+
+DEFINE_INTERRUPT_HANDLER(unknown_exception)
+{
+ printk("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
+ regs->nip, regs->msr, regs->trap);
+
+ _exception(SIGTRAP, regs, TRAP_UNK, 0);
+}
+
+DEFINE_INTERRUPT_HANDLER_ASYNC(unknown_async_exception)
+{
+ printk("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
+ regs->nip, regs->msr, regs->trap);
+
+ _exception(SIGTRAP, regs, TRAP_UNK, 0);
+}
+
+DEFINE_INTERRUPT_HANDLER_NMI(unknown_nmi_exception)
+{
+ printk("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
+ regs->nip, regs->msr, regs->trap);
+
+ _exception(SIGTRAP, regs, TRAP_UNK, 0);
+
+ return 0;
+}
+
+DEFINE_INTERRUPT_HANDLER(instruction_breakpoint_exception)
+{
+ if (notify_die(DIE_IABR_MATCH, "iabr_match", regs, 5,
+ 5, SIGTRAP) == NOTIFY_STOP)
+ return;
+ if (debugger_iabr_match(regs))
+ return;
+ _exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
+}
+
+DEFINE_INTERRUPT_HANDLER(RunModeException)
+{
+ _exception(SIGTRAP, regs, TRAP_UNK, 0);
+}
+
+static void __single_step_exception(struct pt_regs *regs)
+{
+ clear_single_step(regs);
+ clear_br_trace(regs);
+
+ if (kprobe_post_handler(regs))
+ return;
+
+ if (notify_die(DIE_SSTEP, "single_step", regs, 5,
+ 5, SIGTRAP) == NOTIFY_STOP)
+ return;
+ if (debugger_sstep(regs))
+ return;
+
+ _exception(SIGTRAP, regs, TRAP_TRACE, regs->nip);
+}
+
+DEFINE_INTERRUPT_HANDLER(single_step_exception)
+{
+ __single_step_exception(regs);
+}
+
+/*
+ * After we have successfully emulated an instruction, we have to
+ * check if the instruction was being single-stepped, and if so,
+ * pretend we got a single-step exception. This was pointed out
+ * by Kumar Gala. -- paulus
+ */
+void emulate_single_step(struct pt_regs *regs)
+{
+ if (single_stepping(regs))
+ __single_step_exception(regs);
+}
+
+#ifdef CONFIG_PPC_FPU_REGS
+static inline int __parse_fpscr(unsigned long fpscr)
+{
+ int ret = FPE_FLTUNK;
+
+ /* Invalid operation */
+ if ((fpscr & FPSCR_VE) && (fpscr & FPSCR_VX))
+ ret = FPE_FLTINV;
+
+ /* Overflow */
+ else if ((fpscr & FPSCR_OE) && (fpscr & FPSCR_OX))
+ ret = FPE_FLTOVF;
+
+ /* Underflow */
+ else if ((fpscr & FPSCR_UE) && (fpscr & FPSCR_UX))
+ ret = FPE_FLTUND;
+
+ /* Divide by zero */
+ else if ((fpscr & FPSCR_ZE) && (fpscr & FPSCR_ZX))
+ ret = FPE_FLTDIV;
+
+ /* Inexact result */
+ else if ((fpscr & FPSCR_XE) && (fpscr & FPSCR_XX))
+ ret = FPE_FLTRES;
+
+ return ret;
+}
+#endif
+
+static void parse_fpe(struct pt_regs *regs)
+{
+ int code = 0;
+
+ flush_fp_to_thread(current);
+
+#ifdef CONFIG_PPC_FPU_REGS
+ code = __parse_fpscr(current->thread.fp_state.fpscr);
+#endif
+
+ _exception(SIGFPE, regs, code, regs->nip);
+}
+
+/*
+ * Illegal instruction emulation support. Originally written to
+ * provide the PVR to user applications using the mfspr rd, PVR.
+ * Return non-zero if we can't emulate, or -EFAULT if the associated
+ * memory access caused an access fault. Return zero on success.
+ *
+ * There are a couple of ways to do this, either "decode" the instruction
+ * or directly match lots of bits. In this case, matching lots of
+ * bits is faster and easier.
+ *
+ */
+static int emulate_string_inst(struct pt_regs *regs, u32 instword)
+{
+ u8 rT = (instword >> 21) & 0x1f;
+ u8 rA = (instword >> 16) & 0x1f;
+ u8 NB_RB = (instword >> 11) & 0x1f;
+ u32 num_bytes;
+ unsigned long EA;
+ int pos = 0;
+
+ /* Early out if we are an invalid form of lswx */
+ if ((instword & PPC_INST_STRING_MASK) == PPC_INST_LSWX)
+ if ((rT == rA) || (rT == NB_RB))
+ return -EINVAL;
+
+ EA = (rA == 0) ? 0 : regs->gpr[rA];
+
+ switch (instword & PPC_INST_STRING_MASK) {
+ case PPC_INST_LSWX:
+ case PPC_INST_STSWX:
+ EA += NB_RB;
+ num_bytes = regs->xer & 0x7f;
+ break;
+ case PPC_INST_LSWI:
+ case PPC_INST_STSWI:
+ num_bytes = (NB_RB == 0) ? 32 : NB_RB;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ while (num_bytes != 0)
+ {
+ u8 val;
+ u32 shift = 8 * (3 - (pos & 0x3));
+
+ /* if process is 32-bit, clear upper 32 bits of EA */
+ if ((regs->msr & MSR_64BIT) == 0)
+ EA &= 0xFFFFFFFF;
+
+ switch ((instword & PPC_INST_STRING_MASK)) {
+ case PPC_INST_LSWX:
+ case PPC_INST_LSWI:
+ if (get_user(val, (u8 __user *)EA))
+ return -EFAULT;
+ /* first time updating this reg,
+ * zero it out */
+ if (pos == 0)
+ regs->gpr[rT] = 0;
+ regs->gpr[rT] |= val << shift;
+ break;
+ case PPC_INST_STSWI:
+ case PPC_INST_STSWX:
+ val = regs->gpr[rT] >> shift;
+ if (put_user(val, (u8 __user *)EA))
+ return -EFAULT;
+ break;
+ }
+ /* move EA to next address */
+ EA += 1;
+ num_bytes--;
+
+ /* manage our position within the register */
+ if (++pos == 4) {
+ pos = 0;
+ if (++rT == 32)
+ rT = 0;
+ }
+ }
+
+ return 0;
+}
+
+static int emulate_popcntb_inst(struct pt_regs *regs, u32 instword)
+{
+ u32 ra,rs;
+ unsigned long tmp;
+
+ ra = (instword >> 16) & 0x1f;
+ rs = (instword >> 21) & 0x1f;
+
+ tmp = regs->gpr[rs];
+ tmp = tmp - ((tmp >> 1) & 0x5555555555555555ULL);
+ tmp = (tmp & 0x3333333333333333ULL) + ((tmp >> 2) & 0x3333333333333333ULL);
+ tmp = (tmp + (tmp >> 4)) & 0x0f0f0f0f0f0f0f0fULL;
+ regs->gpr[ra] = tmp;
+
+ return 0;
+}
+
+static int emulate_isel(struct pt_regs *regs, u32 instword)
+{
+ u8 rT = (instword >> 21) & 0x1f;
+ u8 rA = (instword >> 16) & 0x1f;
+ u8 rB = (instword >> 11) & 0x1f;
+ u8 BC = (instword >> 6) & 0x1f;
+ u8 bit;
+ unsigned long tmp;
+
+ tmp = (rA == 0) ? 0 : regs->gpr[rA];
+ bit = (regs->ccr >> (31 - BC)) & 0x1;
+
+ regs->gpr[rT] = bit ? tmp : regs->gpr[rB];
+
+ return 0;
+}
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+static inline bool tm_abort_check(struct pt_regs *regs, int cause)
+{
+ /* If we're emulating a load/store in an active transaction, we cannot
+ * emulate it as the kernel operates in transaction suspended context.
+ * We need to abort the transaction. This creates a persistent TM
+ * abort so tell the user what caused it with a new code.
+ */
+ if (MSR_TM_TRANSACTIONAL(regs->msr)) {
+ tm_enable();
+ tm_abort(cause);
+ return true;
+ }
+ return false;
+}
+#else
+static inline bool tm_abort_check(struct pt_regs *regs, int reason)
+{
+ return false;
+}
+#endif
+
+static int emulate_instruction(struct pt_regs *regs)
+{
+ u32 instword;
+ u32 rd;
+
+ if (!user_mode(regs))
+ return -EINVAL;
+
+ if (get_user(instword, (u32 __user *)(regs->nip)))
+ return -EFAULT;
+
+ /* Emulate the mfspr rD, PVR. */
+ if ((instword & PPC_INST_MFSPR_PVR_MASK) == PPC_INST_MFSPR_PVR) {
+ PPC_WARN_EMULATED(mfpvr, regs);
+ rd = (instword >> 21) & 0x1f;
+ regs->gpr[rd] = mfspr(SPRN_PVR);
+ return 0;
+ }
+
+ /* Emulating the dcba insn is just a no-op. */
+ if ((instword & PPC_INST_DCBA_MASK) == PPC_INST_DCBA) {
+ PPC_WARN_EMULATED(dcba, regs);
+ return 0;
+ }
+
+ /* Emulate the mcrxr insn. */
+ if ((instword & PPC_INST_MCRXR_MASK) == PPC_INST_MCRXR) {
+ int shift = (instword >> 21) & 0x1c;
+ unsigned long msk = 0xf0000000UL >> shift;
+
+ PPC_WARN_EMULATED(mcrxr, regs);
+ regs->ccr = (regs->ccr & ~msk) | ((regs->xer >> shift) & msk);
+ regs->xer &= ~0xf0000000UL;
+ return 0;
+ }
+
+ /* Emulate load/store string insn. */
+ if ((instword & PPC_INST_STRING_GEN_MASK) == PPC_INST_STRING) {
+ if (tm_abort_check(regs,
+ TM_CAUSE_EMULATE | TM_CAUSE_PERSISTENT))
+ return -EINVAL;
+ PPC_WARN_EMULATED(string, regs);
+ return emulate_string_inst(regs, instword);
+ }
+
+ /* Emulate the popcntb (Population Count Bytes) instruction. */
+ if ((instword & PPC_INST_POPCNTB_MASK) == PPC_INST_POPCNTB) {
+ PPC_WARN_EMULATED(popcntb, regs);
+ return emulate_popcntb_inst(regs, instword);
+ }
+
+ /* Emulate isel (Integer Select) instruction */
+ if ((instword & PPC_INST_ISEL_MASK) == PPC_INST_ISEL) {
+ PPC_WARN_EMULATED(isel, regs);
+ return emulate_isel(regs, instword);
+ }
+
+ /* Emulate sync instruction variants */
+ if ((instword & PPC_INST_SYNC_MASK) == PPC_INST_SYNC) {
+ PPC_WARN_EMULATED(sync, regs);
+ asm volatile("sync");
+ return 0;
+ }
+
+#ifdef CONFIG_PPC64
+ /* Emulate the mfspr rD, DSCR. */
+ if ((((instword & PPC_INST_MFSPR_DSCR_USER_MASK) ==
+ PPC_INST_MFSPR_DSCR_USER) ||
+ ((instword & PPC_INST_MFSPR_DSCR_MASK) ==
+ PPC_INST_MFSPR_DSCR)) &&
+ cpu_has_feature(CPU_FTR_DSCR)) {
+ PPC_WARN_EMULATED(mfdscr, regs);
+ rd = (instword >> 21) & 0x1f;
+ regs->gpr[rd] = mfspr(SPRN_DSCR);
+ return 0;
+ }
+ /* Emulate the mtspr DSCR, rD. */
+ if ((((instword & PPC_INST_MTSPR_DSCR_USER_MASK) ==
+ PPC_INST_MTSPR_DSCR_USER) ||
+ ((instword & PPC_INST_MTSPR_DSCR_MASK) ==
+ PPC_INST_MTSPR_DSCR)) &&
+ cpu_has_feature(CPU_FTR_DSCR)) {
+ PPC_WARN_EMULATED(mtdscr, regs);
+ rd = (instword >> 21) & 0x1f;
+ current->thread.dscr = regs->gpr[rd];
+ current->thread.dscr_inherit = 1;
+ mtspr(SPRN_DSCR, current->thread.dscr);
+ return 0;
+ }
+#endif
+
+ return -EINVAL;
+}
+
+int is_valid_bugaddr(unsigned long addr)
+{
+ return is_kernel_addr(addr);
+}
+
+#ifdef CONFIG_MATH_EMULATION
+static int emulate_math(struct pt_regs *regs)
+{
+ int ret;
+
+ ret = do_mathemu(regs);
+ if (ret >= 0)
+ PPC_WARN_EMULATED(math, regs);
+
+ switch (ret) {
+ case 0:
+ emulate_single_step(regs);
+ return 0;
+ case 1: {
+ int code = 0;
+ code = __parse_fpscr(current->thread.fp_state.fpscr);
+ _exception(SIGFPE, regs, code, regs->nip);
+ return 0;
+ }
+ case -EFAULT:
+ _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
+ return 0;
+ }
+
+ return -1;
+}
+#else
+static inline int emulate_math(struct pt_regs *regs) { return -1; }
+#endif
+
+static void do_program_check(struct pt_regs *regs)
+{
+ unsigned int reason = get_reason(regs);
+
+ /* We can now get here via a FP Unavailable exception if the core
+ * has no FPU, in that case the reason flags will be 0 */
+
+ if (reason & REASON_FP) {
+ /* IEEE FP exception */
+ parse_fpe(regs);
+ return;
+ }
+ if (reason & REASON_TRAP) {
+ unsigned long bugaddr;
+ /* Debugger is first in line to stop recursive faults in
+ * rcu_lock, notify_die, or atomic_notifier_call_chain */
+ if (debugger_bpt(regs))
+ return;
+
+ if (kprobe_handler(regs))
+ return;
+
+ /* trap exception */
+ if (notify_die(DIE_BPT, "breakpoint", regs, 5, 5, SIGTRAP)
+ == NOTIFY_STOP)
+ return;
+
+ bugaddr = regs->nip;
+ /*
+ * Fixup bugaddr for BUG_ON() in real mode
+ */
+ if (!is_kernel_addr(bugaddr) && !(regs->msr & MSR_IR))
+ bugaddr += PAGE_OFFSET;
+
+ if (!(regs->msr & MSR_PR) && /* not user-mode */
+ report_bug(bugaddr, regs) == BUG_TRAP_TYPE_WARN) {
+ regs_add_return_ip(regs, 4);
+ return;
+ }
+
+ /* User mode considers other cases after enabling IRQs */
+ if (!user_mode(regs)) {
+ _exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
+ return;
+ }
+ }
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+ if (reason & REASON_TM) {
+ /* This is a TM "Bad Thing Exception" program check.
+ * This occurs when:
+ * - An rfid/hrfid/mtmsrd attempts to cause an illegal
+ * transition in TM states.
+ * - A trechkpt is attempted when transactional.
+ * - A treclaim is attempted when non transactional.
+ * - A tend is illegally attempted.
+ * - writing a TM SPR when transactional.
+ *
+ * If usermode caused this, it's done something illegal and
+ * gets a SIGILL slap on the wrist. We call it an illegal
+ * operand to distinguish from the instruction just being bad
+ * (e.g. executing a 'tend' on a CPU without TM!); it's an
+ * illegal /placement/ of a valid instruction.
+ */
+ if (user_mode(regs)) {
+ _exception(SIGILL, regs, ILL_ILLOPN, regs->nip);
+ return;
+ } else {
+ printk(KERN_EMERG "Unexpected TM Bad Thing exception "
+ "at %lx (msr 0x%lx) tm_scratch=%llx\n",
+ regs->nip, regs->msr, get_paca()->tm_scratch);
+ die("Unrecoverable exception", regs, SIGABRT);
+ }
+ }
+#endif
+
+ /*
+ * If we took the program check in the kernel skip down to sending a
+ * SIGILL. The subsequent cases all relate to user space, such as
+ * emulating instructions which we should only do for user space. We
+ * also do not want to enable interrupts for kernel faults because that
+ * might lead to further faults, and loose the context of the original
+ * exception.
+ */
+ if (!user_mode(regs))
+ goto sigill;
+
+ interrupt_cond_local_irq_enable(regs);
+
+ /*
+ * (reason & REASON_TRAP) is mostly handled before enabling IRQs,
+ * except get_user_instr() can sleep so we cannot reliably inspect the
+ * current instruction in that context. Now that we know we are
+ * handling a user space trap and can sleep, we can check if the trap
+ * was a hashchk failure.
+ */
+ if (reason & REASON_TRAP) {
+ if (cpu_has_feature(CPU_FTR_DEXCR_NPHIE)) {
+ ppc_inst_t insn;
+
+ if (get_user_instr(insn, (void __user *)regs->nip)) {
+ _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
+ return;
+ }
+
+ if (ppc_inst_primary_opcode(insn) == 31 &&
+ get_xop(ppc_inst_val(insn)) == OP_31_XOP_HASHCHK) {
+ _exception(SIGILL, regs, ILL_ILLOPN, regs->nip);
+ return;
+ }
+ }
+
+ _exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
+ return;
+ }
+
+ /* (reason & REASON_ILLEGAL) would be the obvious thing here,
+ * but there seems to be a hardware bug on the 405GP (RevD)
+ * that means ESR is sometimes set incorrectly - either to
+ * ESR_DST (!?) or 0. In the process of chasing this with the
+ * hardware people - not sure if it can happen on any illegal
+ * instruction or only on FP instructions, whether there is a
+ * pattern to occurrences etc. -dgibson 31/Mar/2003
+ */
+ if (!emulate_math(regs))
+ return;
+
+ /* Try to emulate it if we should. */
+ if (reason & (REASON_ILLEGAL | REASON_PRIVILEGED)) {
+ switch (emulate_instruction(regs)) {
+ case 0:
+ regs_add_return_ip(regs, 4);
+ emulate_single_step(regs);
+ return;
+ case -EFAULT:
+ _exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
+ return;
+ }
+ }
+
+sigill:
+ if (reason & REASON_PRIVILEGED)
+ _exception(SIGILL, regs, ILL_PRVOPC, regs->nip);
+ else
+ _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
+
+}
+
+DEFINE_INTERRUPT_HANDLER(program_check_exception)
+{
+ do_program_check(regs);
+}
+
+/*
+ * This occurs when running in hypervisor mode on POWER6 or later
+ * and an illegal instruction is encountered.
+ */
+DEFINE_INTERRUPT_HANDLER(emulation_assist_interrupt)
+{
+ regs_set_return_msr(regs, regs->msr | REASON_ILLEGAL);
+ do_program_check(regs);
+}
+
+DEFINE_INTERRUPT_HANDLER(alignment_exception)
+{
+ int sig, code, fixed = 0;
+ unsigned long reason;
+
+ interrupt_cond_local_irq_enable(regs);
+
+ reason = get_reason(regs);
+ if (reason & REASON_BOUNDARY) {
+ sig = SIGBUS;
+ code = BUS_ADRALN;
+ goto bad;
+ }
+
+ if (tm_abort_check(regs, TM_CAUSE_ALIGNMENT | TM_CAUSE_PERSISTENT))
+ return;
+
+ /* we don't implement logging of alignment exceptions */
+ if (!(current->thread.align_ctl & PR_UNALIGN_SIGBUS))
+ fixed = fix_alignment(regs);
+
+ if (fixed == 1) {
+ /* skip over emulated instruction */
+ regs_add_return_ip(regs, inst_length(reason));
+ emulate_single_step(regs);
+ return;
+ }
+
+ /* Operand address was bad */
+ if (fixed == -EFAULT) {
+ sig = SIGSEGV;
+ code = SEGV_ACCERR;
+ } else {
+ sig = SIGBUS;
+ code = BUS_ADRALN;
+ }
+bad:
+ if (user_mode(regs))
+ _exception(sig, regs, code, regs->dar);
+ else
+ bad_page_fault(regs, sig);
+}
+
+DEFINE_INTERRUPT_HANDLER(stack_overflow_exception)
+{
+ die("Kernel stack overflow", regs, SIGSEGV);
+}
+
+DEFINE_INTERRUPT_HANDLER(kernel_fp_unavailable_exception)
+{
+ printk(KERN_EMERG "Unrecoverable FP Unavailable Exception "
+ "%lx at %lx\n", regs->trap, regs->nip);
+ die("Unrecoverable FP Unavailable Exception", regs, SIGABRT);
+}
+
+DEFINE_INTERRUPT_HANDLER(altivec_unavailable_exception)
+{
+ if (user_mode(regs)) {
+ /* A user program has executed an altivec instruction,
+ but this kernel doesn't support altivec. */
+ _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
+ return;
+ }
+
+ printk(KERN_EMERG "Unrecoverable VMX/Altivec Unavailable Exception "
+ "%lx at %lx\n", regs->trap, regs->nip);
+ die("Unrecoverable VMX/Altivec Unavailable Exception", regs, SIGABRT);
+}
+
+DEFINE_INTERRUPT_HANDLER(vsx_unavailable_exception)
+{
+ if (user_mode(regs)) {
+ /* A user program has executed an vsx instruction,
+ but this kernel doesn't support vsx. */
+ _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
+ return;
+ }
+
+ printk(KERN_EMERG "Unrecoverable VSX Unavailable Exception "
+ "%lx at %lx\n", regs->trap, regs->nip);
+ die("Unrecoverable VSX Unavailable Exception", regs, SIGABRT);
+}
+
+#ifdef CONFIG_PPC_BOOK3S_64
+static void tm_unavailable(struct pt_regs *regs)
+{
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+ if (user_mode(regs)) {
+ current->thread.load_tm++;
+ regs_set_return_msr(regs, regs->msr | MSR_TM);
+ tm_enable();
+ tm_restore_sprs(&current->thread);
+ return;
+ }
+#endif
+ pr_emerg("Unrecoverable TM Unavailable Exception "
+ "%lx at %lx\n", regs->trap, regs->nip);
+ die("Unrecoverable TM Unavailable Exception", regs, SIGABRT);
+}
+
+DEFINE_INTERRUPT_HANDLER(facility_unavailable_exception)
+{
+ static char *facility_strings[] = {
+ [FSCR_FP_LG] = "FPU",
+ [FSCR_VECVSX_LG] = "VMX/VSX",
+ [FSCR_DSCR_LG] = "DSCR",
+ [FSCR_PM_LG] = "PMU SPRs",
+ [FSCR_BHRB_LG] = "BHRB",
+ [FSCR_TM_LG] = "TM",
+ [FSCR_EBB_LG] = "EBB",
+ [FSCR_TAR_LG] = "TAR",
+ [FSCR_MSGP_LG] = "MSGP",
+ [FSCR_SCV_LG] = "SCV",
+ [FSCR_PREFIX_LG] = "PREFIX",
+ };
+ char *facility = "unknown";
+ u64 value;
+ u32 instword, rd;
+ u8 status;
+ bool hv;
+
+ hv = (TRAP(regs) == INTERRUPT_H_FAC_UNAVAIL);
+ if (hv)
+ value = mfspr(SPRN_HFSCR);
+ else
+ value = mfspr(SPRN_FSCR);
+
+ status = value >> 56;
+ if ((hv || status >= 2) &&
+ (status < ARRAY_SIZE(facility_strings)) &&
+ facility_strings[status])
+ facility = facility_strings[status];
+
+ /* We should not have taken this interrupt in kernel */
+ if (!user_mode(regs)) {
+ pr_emerg("Facility '%s' unavailable (%d) exception in kernel mode at %lx\n",
+ facility, status, regs->nip);
+ die("Unexpected facility unavailable exception", regs, SIGABRT);
+ }
+
+ interrupt_cond_local_irq_enable(regs);
+
+ if (status == FSCR_DSCR_LG) {
+ /*
+ * User is accessing the DSCR register using the problem
+ * state only SPR number (0x03) either through a mfspr or
+ * a mtspr instruction. If it is a write attempt through
+ * a mtspr, then we set the inherit bit. This also allows
+ * the user to write or read the register directly in the
+ * future by setting via the FSCR DSCR bit. But in case it
+ * is a read DSCR attempt through a mfspr instruction, we
+ * just emulate the instruction instead. This code path will
+ * always emulate all the mfspr instructions till the user
+ * has attempted at least one mtspr instruction. This way it
+ * preserves the same behaviour when the user is accessing
+ * the DSCR through privilege level only SPR number (0x11)
+ * which is emulated through illegal instruction exception.
+ * We always leave HFSCR DSCR set.
+ */
+ if (get_user(instword, (u32 __user *)(regs->nip))) {
+ pr_err("Failed to fetch the user instruction\n");
+ return;
+ }
+
+ /* Write into DSCR (mtspr 0x03, RS) */
+ if ((instword & PPC_INST_MTSPR_DSCR_USER_MASK)
+ == PPC_INST_MTSPR_DSCR_USER) {
+ rd = (instword >> 21) & 0x1f;
+ current->thread.dscr = regs->gpr[rd];
+ current->thread.dscr_inherit = 1;
+ current->thread.fscr |= FSCR_DSCR;
+ mtspr(SPRN_FSCR, current->thread.fscr);
+ }
+
+ /* Read from DSCR (mfspr RT, 0x03) */
+ if ((instword & PPC_INST_MFSPR_DSCR_USER_MASK)
+ == PPC_INST_MFSPR_DSCR_USER) {
+ if (emulate_instruction(regs)) {
+ pr_err("DSCR based mfspr emulation failed\n");
+ return;
+ }
+ regs_add_return_ip(regs, 4);
+ emulate_single_step(regs);
+ }
+ return;
+ }
+
+ if (status == FSCR_TM_LG) {
+ /*
+ * If we're here then the hardware is TM aware because it
+ * generated an exception with FSRM_TM set.
+ *
+ * If cpu_has_feature(CPU_FTR_TM) is false, then either firmware
+ * told us not to do TM, or the kernel is not built with TM
+ * support.
+ *
+ * If both of those things are true, then userspace can spam the
+ * console by triggering the printk() below just by continually
+ * doing tbegin (or any TM instruction). So in that case just
+ * send the process a SIGILL immediately.
+ */
+ if (!cpu_has_feature(CPU_FTR_TM))
+ goto out;
+
+ tm_unavailable(regs);
+ return;
+ }
+
+ pr_err_ratelimited("%sFacility '%s' unavailable (%d), exception at 0x%lx, MSR=%lx\n",
+ hv ? "Hypervisor " : "", facility, status, regs->nip, regs->msr);
+
+out:
+ _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
+}
+#endif
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+
+DEFINE_INTERRUPT_HANDLER(fp_unavailable_tm)
+{
+ /* Note: This does not handle any kind of FP laziness. */
+
+ TM_DEBUG("FP Unavailable trap whilst transactional at 0x%lx, MSR=%lx\n",
+ regs->nip, regs->msr);
+
+ /* We can only have got here if the task started using FP after
+ * beginning the transaction. So, the transactional regs are just a
+ * copy of the checkpointed ones. But, we still need to recheckpoint
+ * as we're enabling FP for the process; it will return, abort the
+ * transaction, and probably retry but now with FP enabled. So the
+ * checkpointed FP registers need to be loaded.
+ */
+ tm_reclaim_current(TM_CAUSE_FAC_UNAV);
+
+ /*
+ * Reclaim initially saved out bogus (lazy) FPRs to ckfp_state, and
+ * then it was overwrite by the thr->fp_state by tm_reclaim_thread().
+ *
+ * At this point, ck{fp,vr}_state contains the exact values we want to
+ * recheckpoint.
+ */
+
+ /* Enable FP for the task: */
+ current->thread.load_fp = 1;
+
+ /*
+ * Recheckpoint all the checkpointed ckpt, ck{fp, vr}_state registers.
+ */
+ tm_recheckpoint(&current->thread);
+}
+
+DEFINE_INTERRUPT_HANDLER(altivec_unavailable_tm)
+{
+ /* See the comments in fp_unavailable_tm(). This function operates
+ * the same way.
+ */
+
+ TM_DEBUG("Vector Unavailable trap whilst transactional at 0x%lx,"
+ "MSR=%lx\n",
+ regs->nip, regs->msr);
+ tm_reclaim_current(TM_CAUSE_FAC_UNAV);
+ current->thread.load_vec = 1;
+ tm_recheckpoint(&current->thread);
+ current->thread.used_vr = 1;
+}
+
+DEFINE_INTERRUPT_HANDLER(vsx_unavailable_tm)
+{
+ /* See the comments in fp_unavailable_tm(). This works similarly,
+ * though we're loading both FP and VEC registers in here.
+ *
+ * If FP isn't in use, load FP regs. If VEC isn't in use, load VEC
+ * regs. Either way, set MSR_VSX.
+ */
+
+ TM_DEBUG("VSX Unavailable trap whilst transactional at 0x%lx,"
+ "MSR=%lx\n",
+ regs->nip, regs->msr);
+
+ current->thread.used_vsr = 1;
+
+ /* This reclaims FP and/or VR regs if they're already enabled */
+ tm_reclaim_current(TM_CAUSE_FAC_UNAV);
+
+ current->thread.load_vec = 1;
+ current->thread.load_fp = 1;
+
+ tm_recheckpoint(&current->thread);
+}
+#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
+
+#ifdef CONFIG_PPC64
+DECLARE_INTERRUPT_HANDLER_NMI(performance_monitor_exception_nmi);
+DEFINE_INTERRUPT_HANDLER_NMI(performance_monitor_exception_nmi)
+{
+ __this_cpu_inc(irq_stat.pmu_irqs);
+
+ perf_irq(regs);
+
+ return 0;
+}
+#endif
+
+DECLARE_INTERRUPT_HANDLER_ASYNC(performance_monitor_exception_async);
+DEFINE_INTERRUPT_HANDLER_ASYNC(performance_monitor_exception_async)
+{
+ __this_cpu_inc(irq_stat.pmu_irqs);
+
+ perf_irq(regs);
+}
+
+DEFINE_INTERRUPT_HANDLER_RAW(performance_monitor_exception)
+{
+ /*
+ * On 64-bit, if perf interrupts hit in a local_irq_disable
+ * (soft-masked) region, we consider them as NMIs. This is required to
+ * prevent hash faults on user addresses when reading callchains (and
+ * looks better from an irq tracing perspective).
+ */
+ if (IS_ENABLED(CONFIG_PPC64) && unlikely(arch_irq_disabled_regs(regs)))
+ performance_monitor_exception_nmi(regs);
+ else
+ performance_monitor_exception_async(regs);
+
+ return 0;
+}
+
+#ifdef CONFIG_PPC_ADV_DEBUG_REGS
+static void handle_debug(struct pt_regs *regs, unsigned long debug_status)
+{
+ int changed = 0;
+ /*
+ * Determine the cause of the debug event, clear the
+ * event flags and send a trap to the handler. Torez
+ */
+ if (debug_status & (DBSR_DAC1R | DBSR_DAC1W)) {
+ dbcr_dac(current) &= ~(DBCR_DAC1R | DBCR_DAC1W);
+#ifdef CONFIG_PPC_ADV_DEBUG_DAC_RANGE
+ current->thread.debug.dbcr2 &= ~DBCR2_DAC12MODE;
+#endif
+ do_send_trap(regs, mfspr(SPRN_DAC1), debug_status,
+ 5);
+ changed |= 0x01;
+ } else if (debug_status & (DBSR_DAC2R | DBSR_DAC2W)) {
+ dbcr_dac(current) &= ~(DBCR_DAC2R | DBCR_DAC2W);
+ do_send_trap(regs, mfspr(SPRN_DAC2), debug_status,
+ 6);
+ changed |= 0x01;
+ } else if (debug_status & DBSR_IAC1) {
+ current->thread.debug.dbcr0 &= ~DBCR0_IAC1;
+ dbcr_iac_range(current) &= ~DBCR_IAC12MODE;
+ do_send_trap(regs, mfspr(SPRN_IAC1), debug_status,
+ 1);
+ changed |= 0x01;
+ } else if (debug_status & DBSR_IAC2) {
+ current->thread.debug.dbcr0 &= ~DBCR0_IAC2;
+ do_send_trap(regs, mfspr(SPRN_IAC2), debug_status,
+ 2);
+ changed |= 0x01;
+ } else if (debug_status & DBSR_IAC3) {
+ current->thread.debug.dbcr0 &= ~DBCR0_IAC3;
+ dbcr_iac_range(current) &= ~DBCR_IAC34MODE;
+ do_send_trap(regs, mfspr(SPRN_IAC3), debug_status,
+ 3);
+ changed |= 0x01;
+ } else if (debug_status & DBSR_IAC4) {
+ current->thread.debug.dbcr0 &= ~DBCR0_IAC4;
+ do_send_trap(regs, mfspr(SPRN_IAC4), debug_status,
+ 4);
+ changed |= 0x01;
+ }
+ /*
+ * At the point this routine was called, the MSR(DE) was turned off.
+ * Check all other debug flags and see if that bit needs to be turned
+ * back on or not.
+ */
+ if (DBCR_ACTIVE_EVENTS(current->thread.debug.dbcr0,
+ current->thread.debug.dbcr1))
+ regs_set_return_msr(regs, regs->msr | MSR_DE);
+ else
+ /* Make sure the IDM flag is off */
+ current->thread.debug.dbcr0 &= ~DBCR0_IDM;
+
+ if (changed & 0x01)
+ mtspr(SPRN_DBCR0, current->thread.debug.dbcr0);
+}
+
+DEFINE_INTERRUPT_HANDLER(DebugException)
+{
+ unsigned long debug_status = regs->dsisr;
+
+ current->thread.debug.dbsr = debug_status;
+
+ /* Hack alert: On BookE, Branch Taken stops on the branch itself, while
+ * on server, it stops on the target of the branch. In order to simulate
+ * the server behaviour, we thus restart right away with a single step
+ * instead of stopping here when hitting a BT
+ */
+ if (debug_status & DBSR_BT) {
+ regs_set_return_msr(regs, regs->msr & ~MSR_DE);
+
+ /* Disable BT */
+ mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~DBCR0_BT);
+ /* Clear the BT event */
+ mtspr(SPRN_DBSR, DBSR_BT);
+
+ /* Do the single step trick only when coming from userspace */
+ if (user_mode(regs)) {
+ current->thread.debug.dbcr0 &= ~DBCR0_BT;
+ current->thread.debug.dbcr0 |= DBCR0_IDM | DBCR0_IC;
+ regs_set_return_msr(regs, regs->msr | MSR_DE);
+ return;
+ }
+
+ if (kprobe_post_handler(regs))
+ return;
+
+ if (notify_die(DIE_SSTEP, "block_step", regs, 5,
+ 5, SIGTRAP) == NOTIFY_STOP) {
+ return;
+ }
+ if (debugger_sstep(regs))
+ return;
+ } else if (debug_status & DBSR_IC) { /* Instruction complete */
+ regs_set_return_msr(regs, regs->msr & ~MSR_DE);
+
+ /* Disable instruction completion */
+ mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~DBCR0_IC);
+ /* Clear the instruction completion event */
+ mtspr(SPRN_DBSR, DBSR_IC);
+
+ if (kprobe_post_handler(regs))
+ return;
+
+ if (notify_die(DIE_SSTEP, "single_step", regs, 5,
+ 5, SIGTRAP) == NOTIFY_STOP) {
+ return;
+ }
+
+ if (debugger_sstep(regs))
+ return;
+
+ if (user_mode(regs)) {
+ current->thread.debug.dbcr0 &= ~DBCR0_IC;
+ if (DBCR_ACTIVE_EVENTS(current->thread.debug.dbcr0,
+ current->thread.debug.dbcr1))
+ regs_set_return_msr(regs, regs->msr | MSR_DE);
+ else
+ /* Make sure the IDM bit is off */
+ current->thread.debug.dbcr0 &= ~DBCR0_IDM;
+ }
+
+ _exception(SIGTRAP, regs, TRAP_TRACE, regs->nip);
+ } else
+ handle_debug(regs, debug_status);
+}
+#endif /* CONFIG_PPC_ADV_DEBUG_REGS */
+
+#ifdef CONFIG_ALTIVEC
+DEFINE_INTERRUPT_HANDLER(altivec_assist_exception)
+{
+ int err;
+
+ if (!user_mode(regs)) {
+ printk(KERN_EMERG "VMX/Altivec assist exception in kernel mode"
+ " at %lx\n", regs->nip);
+ die("Kernel VMX/Altivec assist exception", regs, SIGILL);
+ }
+
+ flush_altivec_to_thread(current);
+
+ PPC_WARN_EMULATED(altivec, regs);
+ err = emulate_altivec(regs);
+ if (err == 0) {
+ regs_add_return_ip(regs, 4); /* skip emulated instruction */
+ emulate_single_step(regs);
+ return;
+ }
+
+ if (err == -EFAULT) {
+ /* got an error reading the instruction */
+ _exception(SIGSEGV, regs, SEGV_ACCERR, regs->nip);
+ } else {
+ /* didn't recognize the instruction */
+ /* XXX quick hack for now: set the non-Java bit in the VSCR */
+ printk_ratelimited(KERN_ERR "Unrecognized altivec instruction "
+ "in %s at %lx\n", current->comm, regs->nip);
+ current->thread.vr_state.vscr.u[3] |= 0x10000;
+ }
+}
+#endif /* CONFIG_ALTIVEC */
+
+#ifdef CONFIG_PPC_85xx
+DEFINE_INTERRUPT_HANDLER(CacheLockingException)
+{
+ unsigned long error_code = regs->dsisr;
+
+ /* We treat cache locking instructions from the user
+ * as priv ops, in the future we could try to do
+ * something smarter
+ */
+ if (error_code & (ESR_DLK|ESR_ILK))
+ _exception(SIGILL, regs, ILL_PRVOPC, regs->nip);
+ return;
+}
+#endif /* CONFIG_PPC_85xx */
+
+#ifdef CONFIG_SPE
+DEFINE_INTERRUPT_HANDLER(SPEFloatingPointException)
+{
+ unsigned long spefscr;
+ int fpexc_mode;
+ int code = FPE_FLTUNK;
+ int err;
+
+ interrupt_cond_local_irq_enable(regs);
+
+ flush_spe_to_thread(current);
+
+ spefscr = current->thread.spefscr;
+ fpexc_mode = current->thread.fpexc_mode;
+
+ if ((spefscr & SPEFSCR_FOVF) && (fpexc_mode & PR_FP_EXC_OVF)) {
+ code = FPE_FLTOVF;
+ }
+ else if ((spefscr & SPEFSCR_FUNF) && (fpexc_mode & PR_FP_EXC_UND)) {
+ code = FPE_FLTUND;
+ }
+ else if ((spefscr & SPEFSCR_FDBZ) && (fpexc_mode & PR_FP_EXC_DIV))
+ code = FPE_FLTDIV;
+ else if ((spefscr & SPEFSCR_FINV) && (fpexc_mode & PR_FP_EXC_INV)) {
+ code = FPE_FLTINV;
+ }
+ else if ((spefscr & (SPEFSCR_FG | SPEFSCR_FX)) && (fpexc_mode & PR_FP_EXC_RES))
+ code = FPE_FLTRES;
+
+ err = do_spe_mathemu(regs);
+ if (err == 0) {
+ regs_add_return_ip(regs, 4); /* skip emulated instruction */
+ emulate_single_step(regs);
+ return;
+ }
+
+ if (err == -EFAULT) {
+ /* got an error reading the instruction */
+ _exception(SIGSEGV, regs, SEGV_ACCERR, regs->nip);
+ } else if (err == -EINVAL) {
+ /* didn't recognize the instruction */
+ printk(KERN_ERR "unrecognized spe instruction "
+ "in %s at %lx\n", current->comm, regs->nip);
+ } else {
+ _exception(SIGFPE, regs, code, regs->nip);
+ }
+
+ return;
+}
+
+DEFINE_INTERRUPT_HANDLER(SPEFloatingPointRoundException)
+{
+ int err;
+
+ interrupt_cond_local_irq_enable(regs);
+
+ preempt_disable();
+ if (regs->msr & MSR_SPE)
+ giveup_spe(current);
+ preempt_enable();
+
+ regs_add_return_ip(regs, -4);
+ err = speround_handler(regs);
+ if (err == 0) {
+ regs_add_return_ip(regs, 4); /* skip emulated instruction */
+ emulate_single_step(regs);
+ return;
+ }
+
+ if (err == -EFAULT) {
+ /* got an error reading the instruction */
+ _exception(SIGSEGV, regs, SEGV_ACCERR, regs->nip);
+ } else if (err == -EINVAL) {
+ /* didn't recognize the instruction */
+ printk(KERN_ERR "unrecognized spe instruction "
+ "in %s at %lx\n", current->comm, regs->nip);
+ } else {
+ _exception(SIGFPE, regs, FPE_FLTUNK, regs->nip);
+ return;
+ }
+}
+#endif
+
+/*
+ * We enter here if we get an unrecoverable exception, that is, one
+ * that happened at a point where the RI (recoverable interrupt) bit
+ * in the MSR is 0. This indicates that SRR0/1 are live, and that
+ * we therefore lost state by taking this exception.
+ */
+void __noreturn unrecoverable_exception(struct pt_regs *regs)
+{
+ pr_emerg("Unrecoverable exception %lx at %lx (msr=%lx)\n",
+ regs->trap, regs->nip, regs->msr);
+ die("Unrecoverable exception", regs, SIGABRT);
+ /* die() should not return */
+ for (;;)
+ ;
+}
+
+#if defined(CONFIG_BOOKE_WDT) || defined(CONFIG_40x)
+DEFINE_INTERRUPT_HANDLER_NMI(WatchdogException)
+{
+ printk (KERN_EMERG "PowerPC Book-E Watchdog Exception\n");
+ mtspr(SPRN_TCR, mfspr(SPRN_TCR) & ~TCR_WIE);
+ return 0;
+}
+#endif
+
+/*
+ * We enter here if we discover during exception entry that we are
+ * running in supervisor mode with a userspace value in the stack pointer.
+ */
+DEFINE_INTERRUPT_HANDLER(kernel_bad_stack)
+{
+ printk(KERN_EMERG "Bad kernel stack pointer %lx at %lx\n",
+ regs->gpr[1], regs->nip);
+ die("Bad kernel stack pointer", regs, SIGABRT);
+}
+
+#ifdef CONFIG_PPC_EMULATED_STATS
+
+#define WARN_EMULATED_SETUP(type) .type = { .name = #type }
+
+struct ppc_emulated ppc_emulated = {
+#ifdef CONFIG_ALTIVEC
+ WARN_EMULATED_SETUP(altivec),
+#endif
+ WARN_EMULATED_SETUP(dcba),
+ WARN_EMULATED_SETUP(dcbz),
+ WARN_EMULATED_SETUP(fp_pair),
+ WARN_EMULATED_SETUP(isel),
+ WARN_EMULATED_SETUP(mcrxr),
+ WARN_EMULATED_SETUP(mfpvr),
+ WARN_EMULATED_SETUP(multiple),
+ WARN_EMULATED_SETUP(popcntb),
+ WARN_EMULATED_SETUP(spe),
+ WARN_EMULATED_SETUP(string),
+ WARN_EMULATED_SETUP(sync),
+ WARN_EMULATED_SETUP(unaligned),
+#ifdef CONFIG_MATH_EMULATION
+ WARN_EMULATED_SETUP(math),
+#endif
+#ifdef CONFIG_VSX
+ WARN_EMULATED_SETUP(vsx),
+#endif
+#ifdef CONFIG_PPC64
+ WARN_EMULATED_SETUP(mfdscr),
+ WARN_EMULATED_SETUP(mtdscr),
+ WARN_EMULATED_SETUP(lq_stq),
+ WARN_EMULATED_SETUP(lxvw4x),
+ WARN_EMULATED_SETUP(lxvh8x),
+ WARN_EMULATED_SETUP(lxvd2x),
+ WARN_EMULATED_SETUP(lxvb16x),
+#endif
+};
+
+u32 ppc_warn_emulated;
+
+void ppc_warn_emulated_print(const char *type)
+{
+ pr_warn_ratelimited("%s used emulated %s instruction\n", current->comm,
+ type);
+}
+
+static int __init ppc_warn_emulated_init(void)
+{
+ struct dentry *dir;
+ unsigned int i;
+ struct ppc_emulated_entry *entries = (void *)&ppc_emulated;
+
+ dir = debugfs_create_dir("emulated_instructions",
+ arch_debugfs_dir);
+
+ debugfs_create_u32("do_warn", 0644, dir, &ppc_warn_emulated);
+
+ for (i = 0; i < sizeof(ppc_emulated)/sizeof(*entries); i++)
+ debugfs_create_u32(entries[i].name, 0644, dir,
+ (u32 *)&entries[i].val.counter);
+
+ return 0;
+}
+
+device_initcall(ppc_warn_emulated_init);
+
+#endif /* CONFIG_PPC_EMULATED_STATS */
generated by cgit v1.2.3 (git 2.39.1) at 2024-08-06 23:43:30 +0000