1 files changed, 17 insertions, 34 deletions

diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index ade32046f3fe..8c03456dade6 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -1,20 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Based on arch/arm/kernel/traps.c
  *
  * Copyright (C) 1995-2009 Russell King
  * Copyright (C) 2012 ARM Ltd.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * 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.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 #include <linux/bug.h>
@@ -66,16 +55,19 @@ static void dump_backtrace_entry(unsigned long where)
 	printk(" %pS\n", (void *)where);
 }
 
-static void __dump_instr(const char *lvl, struct pt_regs *regs)
+static void dump_kernel_instr(const char *lvl, struct pt_regs *regs)
 {
 	unsigned long addr = instruction_pointer(regs);
 	char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str;
 	int i;
 
+	if (user_mode(regs))
+		return;
+
 	for (i = -4; i < 1; i++) {
 		unsigned int val, bad;
 
-		bad = get_user(val, &((u32 *)addr)[i]);
+		bad = aarch64_insn_read(&((u32 *)addr)[i], &val);
 
 		if (!bad)
 			p += sprintf(p, i == 0 ? "(%08x) " : "%08x ", val);
@@ -84,19 +76,8 @@ static void __dump_instr(const char *lvl, struct pt_regs *regs)
 			break;
 		}
 	}
-	printk("%sCode: %s\n", lvl, str);
-}
 
-static void dump_instr(const char *lvl, struct pt_regs *regs)
-{
-	if (!user_mode(regs)) {
-		mm_segment_t fs = get_fs();
-		set_fs(KERNEL_DS);
-		__dump_instr(lvl, regs);
-		set_fs(fs);
-	} else {
-		__dump_instr(lvl, regs);
-	}
+	printk("%sCode: %s\n", lvl, str);
 }
 
 void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
@@ -168,7 +149,6 @@ void show_stack(struct task_struct *tsk, unsigned long *sp)
 
 static int __die(const char *str, int err, struct pt_regs *regs)
 {
-	struct task_struct *tsk = current;
 	static int die_counter;
 	int ret;
 
@@ -181,13 +161,9 @@ static int __die(const char *str, int err, struct pt_regs *regs)
 		return ret;
 
 	print_modules();
-	pr_emerg("Process %.*s (pid: %d, stack limit = 0x%p)\n",
-		 TASK_COMM_LEN, tsk->comm, task_pid_nr(tsk),
-		 end_of_stack(tsk));
 	show_regs(regs);
 
-	if (!user_mode(regs))
-		dump_instr(KERN_EMERG, regs);
+	dump_kernel_instr(KERN_EMERG, regs);
 
 	return ret;
 }
@@ -256,14 +232,17 @@ void arm64_force_sig_fault(int signo, int code, void __user *addr,
 			   const char *str)
 {
 	arm64_show_signal(signo, str);
-	force_sig_fault(signo, code, addr, current);
+	if (signo == SIGKILL)
+		force_sig(SIGKILL);
+	else
+		force_sig_fault(signo, code, addr);
 }
 
 void arm64_force_sig_mceerr(int code, void __user *addr, short lsb,
 			    const char *str)
 {
 	arm64_show_signal(SIGBUS, str);
-	force_sig_mceerr(code, addr, lsb, current);
+	force_sig_mceerr(code, addr, lsb);
 }
 
 void arm64_force_sig_ptrace_errno_trap(int errno, void __user *addr,
@@ -892,6 +871,10 @@ bool arm64_is_fatal_ras_serror(struct pt_regs *regs, unsigned int esr)
 		/*
 		 * The CPU can't make progress. The exception may have
 		 * been imprecise.
+		 *
+		 * Neoverse-N1 #1349291 means a non-KVM SError reported as
+		 * Unrecoverable should be treated as Uncontainable. We
+		 * call arm64_serror_panic() in both cases.
 		 */
 		return true;