From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- arch/arc/kernel/traps.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 159 insertions(+) create mode 100644 arch/arc/kernel/traps.c (limited to 'arch/arc/kernel/traps.c') diff --git a/arch/arc/kernel/traps.c b/arch/arc/kernel/traps.c new file mode 100644 index 000000000..6b83e3f2b --- /dev/null +++ b/arch/arc/kernel/traps.c @@ -0,0 +1,159 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Traps/Non-MMU Exception handling for ARC + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * vineetg: May 2011 + * -user-space unaligned access emulation + * + * Rahul Trivedi: Codito Technologies 2004 + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +void die(const char *str, struct pt_regs *regs, unsigned long address) +{ + show_kernel_fault_diag(str, regs, address); + + /* DEAD END */ + __asm__("flag 1"); +} + +/* + * Helper called for bulk of exceptions NOT needing specific handling + * -for user faults enqueues requested signal + * -for kernel, chk if due to copy_(to|from)_user, otherwise die() + */ +static noinline int +unhandled_exception(const char *str, struct pt_regs *regs, + int signo, int si_code, void __user *addr) +{ + if (user_mode(regs)) { + struct task_struct *tsk = current; + + tsk->thread.fault_address = (__force unsigned int)addr; + + force_sig_fault(signo, si_code, addr); + + } else { + /* If not due to copy_(to|from)_user, we are doomed */ + if (fixup_exception(regs)) + return 0; + + die(str, regs, (unsigned long)addr); + } + + return 1; +} + +#define DO_ERROR_INFO(signr, str, name, sicode) \ +int name(unsigned long address, struct pt_regs *regs) \ +{ \ + return unhandled_exception(str, regs, signr, sicode, \ + (void __user *)address); \ +} + +/* + * Entry points for exceptions NOT needing specific handling + */ +DO_ERROR_INFO(SIGILL, "Priv Op/Disabled Extn", do_privilege_fault, ILL_PRVOPC) +DO_ERROR_INFO(SIGILL, "Invalid Extn Insn", do_extension_fault, ILL_ILLOPC) +DO_ERROR_INFO(SIGILL, "Illegal Insn (or Seq)", insterror_is_error, ILL_ILLOPC) +DO_ERROR_INFO(SIGBUS, "Invalid Mem Access", __weak do_memory_error, BUS_ADRERR) +DO_ERROR_INFO(SIGTRAP, "Breakpoint Set", trap_is_brkpt, TRAP_BRKPT) +DO_ERROR_INFO(SIGBUS, "Misaligned Access", do_misaligned_error, BUS_ADRALN) +DO_ERROR_INFO(SIGSEGV, "gcc generated __builtin_trap", do_trap5_error, 0) + +/* + * Entry Point for Misaligned Data access Exception, for emulating in software + */ +int do_misaligned_access(unsigned long address, struct pt_regs *regs, + struct callee_regs *cregs) +{ + /* If emulation not enabled, or failed, kill the task */ + if (misaligned_fixup(address, regs, cregs) != 0) + return do_misaligned_error(address, regs); + + return 0; +} + +/* + * Entry point for miscll errors such as Nested Exceptions + * -Duplicate TLB entry is handled seperately though + */ +void do_machine_check_fault(unsigned long address, struct pt_regs *regs) +{ + die("Unhandled Machine Check Exception", regs, address); +} + + +/* + * Entry point for traps induced by ARCompact TRAP_S insn + * This is same family as TRAP0/SWI insn (use the same vector). + * The only difference being SWI insn take no operand, while TRAP_S does + * which reflects in ECR Reg as 8 bit param. + * Thus TRAP_S can be used for specific purpose + * -1 used for software breakpointing (gdb) + * -2 used by kprobes + * -5 __builtin_trap() generated by gcc (2018.03 onwards) for toggle such as + * -fno-isolate-erroneous-paths-dereference + */ +void do_non_swi_trap(unsigned long address, struct pt_regs *regs) +{ + unsigned int param = regs->ecr_param; + + switch (param) { + case 1: + trap_is_brkpt(address, regs); + break; + + case 2: + trap_is_kprobe(address, regs); + break; + + case 3: + case 4: + kgdb_trap(regs); + break; + + case 5: + do_trap5_error(address, regs); + break; + default: + break; + } +} + +/* + * Entry point for Instruction Error Exception + * -For a corner case, ARC kprobes implementation resorts to using + * this exception, hence the check + */ +void do_insterror_or_kprobe(unsigned long address, struct pt_regs *regs) +{ + int rc; + + /* Check if this exception is caused by kprobes */ + rc = notify_die(DIE_IERR, "kprobe_ierr", regs, address, 0, SIGILL); + if (rc == NOTIFY_STOP) + return; + + insterror_is_error(address, regs); +} + +/* + * abort() call generated by older gcc for __builtin_trap() + */ +void abort(void) +{ + __asm__ __volatile__("trap_s 5\n"); +} -- cgit v1.2.3