diff options
Diffstat (limited to 'arch/riscv/kernel/traps.c')
| -rw-r--r-- | arch/riscv/kernel/traps.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c new file mode 100644 index 000000000..227253fde --- /dev/null +++ b/arch/riscv/kernel/traps.c @@ -0,0 +1,188 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2012 Regents of the University of California + */ + +#include <linux/cpu.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/sched/debug.h> +#include <linux/sched/signal.h> +#include <linux/signal.h> +#include <linux/kdebug.h> +#include <linux/uaccess.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/irq.h> +#include <linux/kexec.h> + +#include <asm/processor.h> +#include <asm/ptrace.h> +#include <asm/csr.h> + +int show_unhandled_signals = 1; + +extern asmlinkage void handle_exception(void); + +static DEFINE_SPINLOCK(die_lock); + +void die(struct pt_regs *regs, const char *str) +{ + static int die_counter; + int ret; + long cause; + unsigned long flags; + + oops_enter(); + + spin_lock_irqsave(&die_lock, flags); + console_verbose(); + bust_spinlocks(1); + + pr_emerg("%s [#%d]\n", str, ++die_counter); + print_modules(); + if (regs) + show_regs(regs); + + cause = regs ? regs->cause : -1; + ret = notify_die(DIE_OOPS, str, regs, 0, cause, SIGSEGV); + + if (kexec_should_crash(current)) + crash_kexec(regs); + + bust_spinlocks(0); + add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); + spin_unlock_irqrestore(&die_lock, flags); + oops_exit(); + + if (in_interrupt()) + panic("Fatal exception in interrupt"); + if (panic_on_oops) + panic("Fatal exception"); + if (ret != NOTIFY_STOP) + make_task_dead(SIGSEGV); +} + +void do_trap(struct pt_regs *regs, int signo, int code, unsigned long addr) +{ + struct task_struct *tsk = current; + + if (show_unhandled_signals && unhandled_signal(tsk, signo) + && printk_ratelimit()) { + pr_info("%s[%d]: unhandled signal %d code 0x%x at 0x" REG_FMT, + tsk->comm, task_pid_nr(tsk), signo, code, addr); + print_vma_addr(KERN_CONT " in ", instruction_pointer(regs)); + pr_cont("\n"); + show_regs(regs); + } + + force_sig_fault(signo, code, (void __user *)addr); +} + +static void do_trap_error(struct pt_regs *regs, int signo, int code, + unsigned long addr, const char *str) +{ + if (user_mode(regs)) { + do_trap(regs, signo, code, addr); + } else { + if (!fixup_exception(regs)) + die(regs, str); + } +} + +#define DO_ERROR_INFO(name, signo, code, str) \ +asmlinkage __visible void name(struct pt_regs *regs) \ +{ \ + do_trap_error(regs, signo, code, regs->epc, "Oops - " str); \ +} + +DO_ERROR_INFO(do_trap_unknown, + SIGILL, ILL_ILLTRP, "unknown exception"); +DO_ERROR_INFO(do_trap_insn_misaligned, + SIGBUS, BUS_ADRALN, "instruction address misaligned"); +DO_ERROR_INFO(do_trap_insn_fault, + SIGSEGV, SEGV_ACCERR, "instruction access fault"); +DO_ERROR_INFO(do_trap_insn_illegal, + SIGILL, ILL_ILLOPC, "illegal instruction"); +DO_ERROR_INFO(do_trap_load_fault, + SIGSEGV, SEGV_ACCERR, "load access fault"); +#ifndef CONFIG_RISCV_M_MODE +DO_ERROR_INFO(do_trap_load_misaligned, + SIGBUS, BUS_ADRALN, "Oops - load address misaligned"); +DO_ERROR_INFO(do_trap_store_misaligned, + SIGBUS, BUS_ADRALN, "Oops - store (or AMO) address misaligned"); +#else +int handle_misaligned_load(struct pt_regs *regs); +int handle_misaligned_store(struct pt_regs *regs); + +asmlinkage void do_trap_load_misaligned(struct pt_regs *regs) +{ + if (!handle_misaligned_load(regs)) + return; + do_trap_error(regs, SIGBUS, BUS_ADRALN, regs->epc, + "Oops - load address misaligned"); +} + +asmlinkage void do_trap_store_misaligned(struct pt_regs *regs) +{ + if (!handle_misaligned_store(regs)) + return; + do_trap_error(regs, SIGBUS, BUS_ADRALN, regs->epc, + "Oops - store (or AMO) address misaligned"); +} +#endif +DO_ERROR_INFO(do_trap_store_fault, + SIGSEGV, SEGV_ACCERR, "store (or AMO) access fault"); +DO_ERROR_INFO(do_trap_ecall_u, + SIGILL, ILL_ILLTRP, "environment call from U-mode"); +DO_ERROR_INFO(do_trap_ecall_s, + SIGILL, ILL_ILLTRP, "environment call from S-mode"); +DO_ERROR_INFO(do_trap_ecall_m, + SIGILL, ILL_ILLTRP, "environment call from M-mode"); + +static inline unsigned long get_break_insn_length(unsigned long pc) +{ + bug_insn_t insn; + + if (get_kernel_nofault(insn, (bug_insn_t *)pc)) + return 0; + + return GET_INSN_LENGTH(insn); +} + +asmlinkage __visible void do_trap_break(struct pt_regs *regs) +{ + if (user_mode(regs)) + force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->epc); +#ifdef CONFIG_KGDB + else if (notify_die(DIE_TRAP, "EBREAK", regs, 0, regs->cause, SIGTRAP) + == NOTIFY_STOP) + return; +#endif + else if (report_bug(regs->epc, regs) == BUG_TRAP_TYPE_WARN) + regs->epc += get_break_insn_length(regs->epc); + else + die(regs, "Kernel BUG"); +} + +#ifdef CONFIG_GENERIC_BUG +int is_valid_bugaddr(unsigned long pc) +{ + bug_insn_t insn; + + if (pc < VMALLOC_START) + return 0; + if (get_kernel_nofault(insn, (bug_insn_t *)pc)) + return 0; + if ((insn & __INSN_LENGTH_MASK) == __INSN_LENGTH_32) + return (insn == __BUG_INSN_32); + else + return ((insn & __COMPRESSED_INSN_MASK) == __BUG_INSN_16); +} +#endif /* CONFIG_GENERIC_BUG */ + +/* stvec & scratch is already set from head.S */ +void trap_init(void) +{ +} |