From patchwork Mon Aug 14 03:52:59 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tiezhu Yang X-Patchwork-Id: 13352330 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 629DEC04FDF for ; Mon, 14 Aug 2023 03:54:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233048AbjHNDxj (ORCPT ); Sun, 13 Aug 2023 23:53:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54056 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233028AbjHNDxM (ORCPT ); Sun, 13 Aug 2023 23:53:12 -0400 Received: from mail.loongson.cn (mail.loongson.cn [114.242.206.163]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id BC500E53; Sun, 13 Aug 2023 20:53:10 -0700 (PDT) Received: from loongson.cn (unknown [113.200.148.30]) by gateway (Coremail) with SMTP id _____8Cx2eogpdlku+UXAA--.44450S3; Mon, 14 Aug 2023 11:53:04 +0800 (CST) Received: from linux.localdomain (unknown [113.200.148.30]) by localhost.localdomain (Coremail) with SMTP id AQAAf8CxriMdpdlkLVBZAA--.48641S3; Mon, 14 Aug 2023 11:53:02 +0800 (CST) From: Tiezhu Yang To: Thomas Bogendoerfer Cc: "Maciej W. Rozycki" , linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, loongson-kernel@lists.loongnix.cn Subject: [PATCH v2 1/3] MIPS: Remove noreturn attribute for die() Date: Mon, 14 Aug 2023 11:52:59 +0800 Message-Id: <1691985181-28363-2-git-send-email-yangtiezhu@loongson.cn> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1691985181-28363-1-git-send-email-yangtiezhu@loongson.cn> References: <1691985181-28363-1-git-send-email-yangtiezhu@loongson.cn> X-CM-TRANSID: AQAAf8CxriMdpdlkLVBZAA--.48641S3 X-CM-SenderInfo: p1dqw3xlh2x3gn0dqz5rrqw2lrqou0/ X-Coremail-Antispam: 1Uk129KBj93XoW7AFy5uFW7XF1xJF4rAFy3ZFc_yoW8CrW8pr 4jka4DKryDXF4DXrykAa1DGFW3uFZYq3y2kw4qkw4F9wnIyw1rXF4kGFWY9w4rKryrWa4q qFWjqr18AFZ7AFcCm3ZEXasCq-sJn29KB7ZKAUJUUUUr529EdanIXcx71UUUUU7KY7ZEXa sCq-sGcSsGvfJ3Ic02F40EFcxC0VAKzVAqx4xG6I80ebIjqfuFe4nvWSU5nxnvy29KBjDU 0xBIdaVrnRJUUU9Fb4IE77IF4wAFF20E14v26r1j6r4UM7CY07I20VC2zVCF04k26cxKx2 IYs7xG6rWj6s0DM7CIcVAFz4kK6r1Y6r17M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48v e4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Gr0_Xr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI 0_Gr0_Cr1l84ACjcxK6I8E87Iv67AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVCY1x0267AK xVW8Jr0_Cr1UM2kKe7AKxVWUXVWUAwAS0I0E0xvYzxvE52x082IY62kv0487Mc804VCY07 AIYIkI8VC2zVCFFI0UMc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWU AVWUtwAv7VC2z280aVAFwI0_Gr0_Cr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7V AKI48JMxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMxCIbckI1I0E14v2 6r1Y6r17MI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17 CEb7AF67AKxVWUAVWUtwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1I6r4UMIIF 0xvE2Ix0cI8IcVCY1x0267AKxVWUJVW8JwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIx AIcVC2z280aVAFwI0_Gr0_Cr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2 KfnxnUUI43ZEXa7IU8uuWJUUUUU== Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org If notify_die() returns NOTIFY_STOP, honor the return value from the handler chain invocation in die() as, through a debugger, the fault may have been fixed. It makes sense even if ignoring the event will make the system unstable, by allowing access through a debugger it has been compromised already anyway. So we can remove the noreturn attribute for die() to make our port consistent with x86, arm64, riscv and csky. Commit 20c0d2d44029 ("[PATCH] i386: pass proper trap numbers to die chain handlers") may be the earliest of similar changes. Link: https://lore.kernel.org/all/alpine.DEB.2.21.2308132148500.8596@angie.orcam.me.uk/ Signed-off-by: Tiezhu Yang --- arch/mips/kernel/traps.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index 246c6a6..62d6c4e 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -391,16 +391,15 @@ void show_registers(struct pt_regs *regs) static DEFINE_RAW_SPINLOCK(die_lock); -void __noreturn die(const char *str, struct pt_regs *regs) +void die(const char *str, struct pt_regs *regs) { static int die_counter; - int sig = SIGSEGV; + int ret; oops_enter(); - if (notify_die(DIE_OOPS, str, regs, 0, current->thread.trap_nr, - SIGSEGV) == NOTIFY_STOP) - sig = 0; + ret = notify_die(DIE_OOPS, str, regs, 0, + current->thread.trap_nr, SIGSEGV); console_verbose(); raw_spin_lock_irq(&die_lock); @@ -422,7 +421,8 @@ void __noreturn die(const char *str, struct pt_regs *regs) if (regs && kexec_should_crash(current)) crash_kexec(regs); - make_task_dead(sig); + if (ret != NOTIFY_STOP) + make_task_dead(SIGSEGV); } extern struct exception_table_entry __start___dbe_table[];