diff options
Diffstat (limited to 'arch/riscv/kernel/traps.c')
| -rw-r--r-- | arch/riscv/kernel/traps.c | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c new file mode 100644 index 000000000000..93132cb59184 --- /dev/null +++ b/arch/riscv/kernel/traps.c @@ -0,0 +1,180 @@ +/* + * Copyright (C) 2012 Regents of the University of California + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#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 <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; + + oops_enter(); + + spin_lock_irq(&die_lock); + console_verbose(); + bust_spinlocks(1); + + pr_emerg("%s [#%d]\n", str, ++die_counter); + print_modules(); + show_regs(regs); + + ret = notify_die(DIE_OOPS, str, regs, 0, regs->scause, SIGSEGV); + + bust_spinlocks(0); + add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); + spin_unlock_irq(&die_lock); + oops_exit(); + + if (in_interrupt()) + panic("Fatal exception in interrupt"); + if (panic_on_oops) + panic("Fatal exception"); + if (ret != NOTIFY_STOP) + do_exit(SIGSEGV); +} + +static inline void do_trap_siginfo(int signo, int code, + unsigned long addr, struct task_struct *tsk) +{ + siginfo_t info; + + info.si_signo = signo; + info.si_errno = 0; + info.si_code = code; + info.si_addr = (void __user *)addr; + force_sig_info(signo, &info, tsk); +} + +void do_trap(struct pt_regs *regs, int signo, int code, + unsigned long addr, struct task_struct *tsk) +{ + 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 ", GET_IP(regs)); + pr_cont("\n"); + show_regs(regs); + } + + do_trap_siginfo(signo, code, addr, tsk); +} + +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, current); + } else { + if (!fixup_exception(regs)) + die(regs, str); + } +} + +#define DO_ERROR_INFO(name, signo, code, str) \ +asmlinkage void name(struct pt_regs *regs) \ +{ \ + do_trap_error(regs, signo, code, regs->sepc, "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_misaligned, + SIGBUS, BUS_ADRALN, "load address misaligned"); +DO_ERROR_INFO(do_trap_load_fault, + SIGSEGV, SEGV_ACCERR, "load access fault"); +DO_ERROR_INFO(do_trap_store_misaligned, + SIGBUS, BUS_ADRALN, "store (or AMO) address misaligned"); +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"); + +asmlinkage void do_trap_break(struct pt_regs *regs) +{ +#ifdef CONFIG_GENERIC_BUG + if (!user_mode(regs)) { + enum bug_trap_type type; + + type = report_bug(regs->sepc, regs); + switch (type) { + case BUG_TRAP_TYPE_NONE: + break; + case BUG_TRAP_TYPE_WARN: + regs->sepc += sizeof(bug_insn_t); + return; + case BUG_TRAP_TYPE_BUG: + die(regs, "Kernel BUG"); + } + } +#endif /* CONFIG_GENERIC_BUG */ + + do_trap_siginfo(SIGTRAP, TRAP_BRKPT, regs->sepc, current); + regs->sepc += 0x4; +} + +#ifdef CONFIG_GENERIC_BUG +int is_valid_bugaddr(unsigned long pc) +{ + bug_insn_t insn; + + if (pc < PAGE_OFFSET) + return 0; + if (probe_kernel_address((bug_insn_t __user *)pc, insn)) + return 0; + return (insn == __BUG_INSN); +} +#endif /* CONFIG_GENERIC_BUG */ + +void __init trap_init(void) +{ + /* + * Set sup0 scratch register to 0, indicating to exception vector + * that we are presently executing in the kernel + */ + csr_write(sscratch, 0); + /* Set the exception vector address */ + csr_write(stvec, &handle_exception); + /* Enable all interrupts */ + csr_write(sie, -1); +} |