diff options
Diffstat (limited to 'arch/nds32/kernel/traps.c')
| -rw-r--r-- | arch/nds32/kernel/traps.c | 385 |
1 files changed, 385 insertions, 0 deletions
diff --git a/arch/nds32/kernel/traps.c b/arch/nds32/kernel/traps.c new file mode 100644 index 000000000..1496aab48 --- /dev/null +++ b/arch/nds32/kernel/traps.c @@ -0,0 +1,385 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2005-2017 Andes Technology Corporation + +#include <linux/module.h> +#include <linux/personality.h> +#include <linux/kallsyms.h> +#include <linux/hardirq.h> +#include <linux/kdebug.h> +#include <linux/sched/task_stack.h> +#include <linux/uaccess.h> +#include <linux/ftrace.h> + +#include <asm/proc-fns.h> +#include <asm/unistd.h> + +#include <linux/ptrace.h> +#include <nds32_intrinsic.h> + +extern void show_pte(struct mm_struct *mm, unsigned long addr); + +/* + * Dump out the contents of some memory nicely... + */ +void dump_mem(const char *lvl, unsigned long bottom, unsigned long top) +{ + unsigned long first; + mm_segment_t fs; + int i; + + /* + * We need to switch to kernel mode so that we can use __get_user + * to safely read from kernel space. Note that we now dump the + * code first, just in case the backtrace kills us. + */ + fs = get_fs(); + set_fs(KERNEL_DS); + + pr_emerg("%s(0x%08lx to 0x%08lx)\n", lvl, bottom, top); + + for (first = bottom & ~31; first < top; first += 32) { + unsigned long p; + char str[sizeof(" 12345678") * 8 + 1]; + + memset(str, ' ', sizeof(str)); + str[sizeof(str) - 1] = '\0'; + + for (p = first, i = 0; i < 8 && p < top; i++, p += 4) { + if (p >= bottom && p < top) { + unsigned long val; + if (__get_user(val, (unsigned long *)p) == 0) + sprintf(str + i * 9, " %08lx", val); + else + sprintf(str + i * 9, " ????????"); + } + } + pr_emerg("%s%04lx:%s\n", lvl, first & 0xffff, str); + } + + set_fs(fs); +} + +EXPORT_SYMBOL(dump_mem); + +static void dump_instr(struct pt_regs *regs) +{ + unsigned long addr = instruction_pointer(regs); + mm_segment_t fs; + char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str; + int i; + + return; + /* + * We need to switch to kernel mode so that we can use __get_user + * to safely read from kernel space. Note that we now dump the + * code first, just in case the backtrace kills us. + */ + fs = get_fs(); + set_fs(KERNEL_DS); + + pr_emerg("Code: "); + for (i = -4; i < 1; i++) { + unsigned int val, bad; + + bad = __get_user(val, &((u32 *) addr)[i]); + + if (!bad) { + p += sprintf(p, i == 0 ? "(%08x) " : "%08x ", val); + } else { + p += sprintf(p, "bad PC value"); + break; + } + } + pr_emerg("Code: %s\n", str); + + set_fs(fs); +} + +#define LOOP_TIMES (100) +static void __dump(struct task_struct *tsk, unsigned long *base_reg) +{ + unsigned long ret_addr; + int cnt = LOOP_TIMES, graph = 0; + pr_emerg("Call Trace:\n"); + if (!IS_ENABLED(CONFIG_FRAME_POINTER)) { + while (!kstack_end(base_reg)) { + ret_addr = *base_reg++; + if (__kernel_text_address(ret_addr)) { + ret_addr = ftrace_graph_ret_addr( + tsk, &graph, ret_addr, NULL); + print_ip_sym(ret_addr); + } + if (--cnt < 0) + break; + } + } else { + while (!kstack_end((void *)base_reg) && + !((unsigned long)base_reg & 0x3) && + ((unsigned long)base_reg >= TASK_SIZE)) { + unsigned long next_fp; + ret_addr = base_reg[LP_OFFSET]; + next_fp = base_reg[FP_OFFSET]; + if (__kernel_text_address(ret_addr)) { + + ret_addr = ftrace_graph_ret_addr( + tsk, &graph, ret_addr, NULL); + print_ip_sym(ret_addr); + } + if (--cnt < 0) + break; + base_reg = (unsigned long *)next_fp; + } + } + pr_emerg("\n"); +} + +void show_stack(struct task_struct *tsk, unsigned long *sp) +{ + unsigned long *base_reg; + + if (!tsk) + tsk = current; + if (!IS_ENABLED(CONFIG_FRAME_POINTER)) { + if (tsk != current) + base_reg = (unsigned long *)(tsk->thread.cpu_context.sp); + else + __asm__ __volatile__("\tori\t%0, $sp, #0\n":"=r"(base_reg)); + } else { + if (tsk != current) + base_reg = (unsigned long *)(tsk->thread.cpu_context.fp); + else + __asm__ __volatile__("\tori\t%0, $fp, #0\n":"=r"(base_reg)); + } + __dump(tsk, base_reg); + barrier(); +} + +DEFINE_SPINLOCK(die_lock); + +/* + * This function is protected against re-entrancy. + */ +void die(const char *str, struct pt_regs *regs, int err) +{ + struct task_struct *tsk = current; + static int die_counter; + + console_verbose(); + spin_lock_irq(&die_lock); + bust_spinlocks(1); + + pr_emerg("Internal error: %s: %x [#%d]\n", str, err, ++die_counter); + print_modules(); + pr_emerg("CPU: %i\n", smp_processor_id()); + show_regs(regs); + pr_emerg("Process %s (pid: %d, stack limit = 0x%p)\n", + tsk->comm, tsk->pid, end_of_stack(tsk)); + + if (!user_mode(regs) || in_interrupt()) { + dump_mem("Stack: ", regs->sp, (regs->sp + PAGE_SIZE) & PAGE_MASK); + dump_instr(regs); + dump_stack(); + } + + bust_spinlocks(0); + spin_unlock_irq(&die_lock); + do_exit(SIGSEGV); +} + +EXPORT_SYMBOL(die); + +void die_if_kernel(const char *str, struct pt_regs *regs, int err) +{ + if (user_mode(regs)) + return; + + die(str, regs, err); +} + +int bad_syscall(int n, struct pt_regs *regs) +{ + if (current->personality != PER_LINUX) { + send_sig(SIGSEGV, current, 1); + return regs->uregs[0]; + } + + force_sig_fault(SIGILL, ILL_ILLTRP, + (void __user *)instruction_pointer(regs) - 4, current); + die_if_kernel("Oops - bad syscall", regs, n); + return regs->uregs[0]; +} + +void __pte_error(const char *file, int line, unsigned long val) +{ + pr_emerg("%s:%d: bad pte %08lx.\n", file, line, val); +} + +void __pmd_error(const char *file, int line, unsigned long val) +{ + pr_emerg("%s:%d: bad pmd %08lx.\n", file, line, val); +} + +void __pgd_error(const char *file, int line, unsigned long val) +{ + pr_emerg("%s:%d: bad pgd %08lx.\n", file, line, val); +} + +extern char *exception_vector, *exception_vector_end; +void __init trap_init(void) +{ + return; +} + +void __init early_trap_init(void) +{ + unsigned long ivb = 0; + unsigned long base = PAGE_OFFSET; + + memcpy((unsigned long *)base, (unsigned long *)&exception_vector, + ((unsigned long)&exception_vector_end - + (unsigned long)&exception_vector)); + ivb = __nds32__mfsr(NDS32_SR_IVB); + /* Check platform support. */ + if (((ivb & IVB_mskNIVIC) >> IVB_offNIVIC) < 2) + panic + ("IVIC mode is not allowed on the platform with interrupt controller\n"); + __nds32__mtsr((ivb & ~IVB_mskESZ) | (IVB_valESZ16 << IVB_offESZ) | + IVB_BASE, NDS32_SR_IVB); + __nds32__mtsr(INT_MASK_INITAIAL_VAL, NDS32_SR_INT_MASK); + + /* + * 0x800 = 128 vectors * 16byte. + * It should be enough to flush a page. + */ + cpu_cache_wbinval_page(base, true); +} + +void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, + int error_code, int si_code) +{ + tsk->thread.trap_no = ENTRY_DEBUG_RELATED; + tsk->thread.error_code = error_code; + + force_sig_fault(SIGTRAP, si_code, + (void __user *)instruction_pointer(regs), tsk); +} + +void do_debug_trap(unsigned long entry, unsigned long addr, + unsigned long type, struct pt_regs *regs) +{ + if (notify_die(DIE_OOPS, "Oops", regs, addr, type, SIGTRAP) + == NOTIFY_STOP) + return; + + if (user_mode(regs)) { + /* trap_signal */ + send_sigtrap(current, regs, 0, TRAP_BRKPT); + } else { + /* kernel_trap */ + if (!fixup_exception(regs)) + die("unexpected kernel_trap", regs, 0); + } +} + +void unhandled_interruption(struct pt_regs *regs) +{ + pr_emerg("unhandled_interruption\n"); + show_regs(regs); + if (!user_mode(regs)) + do_exit(SIGKILL); + force_sig(SIGKILL, current); +} + +void unhandled_exceptions(unsigned long entry, unsigned long addr, + unsigned long type, struct pt_regs *regs) +{ + pr_emerg("Unhandled Exception: entry: %lx addr:%lx itype:%lx\n", entry, + addr, type); + show_regs(regs); + if (!user_mode(regs)) + do_exit(SIGKILL); + force_sig(SIGKILL, current); +} + +extern int do_page_fault(unsigned long entry, unsigned long addr, + unsigned int error_code, struct pt_regs *regs); + +/* + * 2:DEF dispatch for TLB MISC exception handler +*/ + +void do_dispatch_tlb_misc(unsigned long entry, unsigned long addr, + unsigned long type, struct pt_regs *regs) +{ + type = type & (ITYPE_mskINST | ITYPE_mskETYPE); + if ((type & ITYPE_mskETYPE) < 5) { + /* Permission exceptions */ + do_page_fault(entry, addr, type, regs); + } else + unhandled_exceptions(entry, addr, type, regs); +} + +void do_revinsn(struct pt_regs *regs) +{ + pr_emerg("Reserved Instruction\n"); + show_regs(regs); + if (!user_mode(regs)) + do_exit(SIGILL); + force_sig(SIGILL, current); +} + +#ifdef CONFIG_ALIGNMENT_TRAP +extern int unalign_access_mode; +extern int do_unaligned_access(unsigned long addr, struct pt_regs *regs); +#endif +void do_dispatch_general(unsigned long entry, unsigned long addr, + unsigned long itype, struct pt_regs *regs, + unsigned long oipc) +{ + unsigned int swid = itype >> ITYPE_offSWID; + unsigned long type = itype & (ITYPE_mskINST | ITYPE_mskETYPE); + if (type == ETYPE_ALIGNMENT_CHECK) { +#ifdef CONFIG_ALIGNMENT_TRAP + /* Alignment check */ + if (user_mode(regs) && unalign_access_mode) { + int ret; + ret = do_unaligned_access(addr, regs); + + if (ret == 0) + return; + + if (ret == -EFAULT) + pr_emerg + ("Unhandled unaligned access exception\n"); + } +#endif + do_page_fault(entry, addr, type, regs); + } else if (type == ETYPE_RESERVED_INSTRUCTION) { + /* Reserved instruction */ + do_revinsn(regs); + } else if (type == ETYPE_TRAP && swid == SWID_RAISE_INTERRUPT_LEVEL) { + /* trap, used on v3 EDM target debugging workaround */ + /* + * DIPC(OIPC) is passed as parameter before + * interrupt is enabled, so the DIPC will not be corrupted + * even though interrupts are coming in + */ + /* + * 1. update ipc + * 2. update pt_regs ipc with oipc + * 3. update pt_regs ipsw (clear DEX) + */ + __asm__ volatile ("mtsr %0, $IPC\n\t"::"r" (oipc)); + regs->ipc = oipc; + if (regs->pipsw & PSW_mskDEX) { + pr_emerg + ("Nested Debug exception is possibly happened\n"); + pr_emerg("ipc:%08x pipc:%08x\n", + (unsigned int)regs->ipc, + (unsigned int)regs->pipc); + } + do_debug_trap(entry, addr, itype, regs); + regs->ipsw &= ~PSW_mskDEX; + } else + unhandled_exceptions(entry, addr, type, regs); +} |