From patchwork Thu Feb 28 10:31:31 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vincent Chen X-Patchwork-Id: 10832765 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A5EE713B5 for ; Thu, 28 Feb 2019 10:32:20 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 916E82E472 for ; Thu, 28 Feb 2019 10:32:20 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 859F52E498; Thu, 28 Feb 2019 10:32:20 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 11A052E472 for ; Thu, 28 Feb 2019 10:32:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=AX7G3bWMiOccA6JfJHSGvsFVJRWvk3wmTLAR4PxJr80=; b=CZKSRMQmt0qKVT +1GUsDbJLOrX2m3DNurgCQwvEJtH1E6DZyTs0PCmzHznoFLmRCku+xpZqiOEvVTB2+MO28b4vNfFS iv3MjVQ2vy2jayix2oWpfTiZbqKTARvl+Pl49L0xVisX1lyB1ZGI4gjeHbdFj7IT64zsDeYI2hQ82 jwEyfvHBz3OtUL1Wnkb8h/2xa6QRzjpaFbVvjwgfJ6HslP5Xd+xG2AbdOqi6ye6guIEsIRKetLcEF k8MW4FWlX6FTD9bedA2fJ7MytB22OiLh8zGkCG+HouAVCA7s1aviCku2c/z87oA7KEQtfRqbiRXc1 3vAka2A7jT1lPzftLt4g==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gzIzB-0000ni-QB; Thu, 28 Feb 2019 10:32:17 +0000 Received: from 59-120-53-16.hinet-ip.hinet.net ([59.120.53.16] helo=ATCSQR.andestech.com) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gzIz8-0000kW-Pf for linux-riscv@lists.infradead.org; Thu, 28 Feb 2019 10:32:16 +0000 Received: from mail.andestech.com (atcpcs16.andestech.com [10.0.1.222]) by ATCSQR.andestech.com with ESMTP id x1SAVDs7086841; Thu, 28 Feb 2019 18:31:13 +0800 (GMT-8) (envelope-from vincentc@andestech.com) Received: from atcsqa06.andestech.com (10.0.15.65) by ATCPCS16.andestech.com (10.0.1.222) with Microsoft SMTP Server id 14.3.123.3; Thu, 28 Feb 2019 18:31:47 +0800 From: Vincent Chen To: , , , , , , Subject: [PATCH 3/3] riscv: Make WARN() related functions able to trigger a trap exception Date: Thu, 28 Feb 2019 18:31:31 +0800 Message-ID: <1551349891-22683-4-git-send-email-vincentc@andestech.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1551349891-22683-1-git-send-email-vincentc@andestech.com> References: <1551349891-22683-1-git-send-email-vincentc@andestech.com> MIME-Version: 1.0 X-Originating-IP: [10.0.15.65] X-DNSRBL: X-MAIL: ATCSQR.andestech.com x1SAVDs7086841 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190228_023215_150497_9C4B0D33 X-CRM114-Status: UNSURE ( 7.92 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: vincentc@andestech.com, deanbo422@gmail.com Sender: "linux-riscv" Errors-To: linux-riscv-bounces+patchwork-linux-riscv=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP This can help developers to analyze the cause of WARN() because the control will be transferred to debugging environment if the debugger is connected. Signed-off-by: Vincent Chen --- arch/riscv/include/asm/bug.h | 27 ++++++++++++++++++--------- arch/riscv/kernel/traps.c | 19 ++++++++++++++++--- 2 files changed, 34 insertions(+), 12 deletions(-) diff --git a/arch/riscv/include/asm/bug.h b/arch/riscv/include/asm/bug.h index 1cab7f4..b2aa88f 100644 --- a/arch/riscv/include/asm/bug.h +++ b/arch/riscv/include/asm/bug.h @@ -43,38 +43,47 @@ #define __BUG_ENTRY \ __BUG_ENTRY_ADDR "\n\t" \ __BUG_ENTRY_FILE "\n\t" \ - RISCV_SHORT " %1" + RISCV_SHORT " %1 \n\t" \ + RISCV_SHORT " %2" #else #define __BUG_ENTRY \ - __BUG_ENTRY_ADDR + __BUG_ENTRY_ADDR "\n\t" \ + RISCV_SHORT " %2" #endif -#define BUG() \ +#define __BUG_FLAGS(flags) \ do { \ __asm__ __volatile__ ( \ "1:\n\t" \ "ebreak\n" \ - ".pushsection __bug_table,\"a\"\n\t" \ + ".pushsection __bug_table,\"aw\"\n\t" \ "2:\n\t" \ __BUG_ENTRY "\n\t" \ - ".org 2b + %2\n\t" \ + ".org 2b + %3\n\t" \ ".popsection" \ : \ : "i" (__FILE__), "i" (__LINE__), \ - "i" (sizeof(struct bug_entry))); \ - unreachable(); \ + "i" (flags), \ + "i" (sizeof(struct bug_entry))); \ } while (0) + #endif /* !__ASSEMBLY__ */ #else /* CONFIG_GENERIC_BUG */ #ifndef __ASSEMBLY__ -#define BUG() \ +#define __BUG_FLAGS(flags) \ do { \ __asm__ __volatile__ ("ebreak\n"); \ - unreachable(); \ } while (0) #endif /* !__ASSEMBLY__ */ #endif /* CONFIG_GENERIC_BUG */ +#define BUG() do { \ + __BUG_FLAGS(0); \ + unreachable(); \ +} while (0) + +#define __WARN_FLAGS(flags) __BUG_FLAGS(BUGFLAG_WARNING|(flags)) + #define HAVE_ARCH_BUG #include diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index dee0e5e..023208b 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -118,6 +118,17 @@ asmlinkage void name(struct pt_regs *regs) \ DO_ERROR_INFO(do_trap_ecall_m, SIGILL, ILL_ILLTRP, "environment call from M-mode"); +#ifdef CONFIG_GENERIC_BUG +static inline unsigned long get_break_insn_length(unsigned long pc) +{ + bug_insn_t insn; + + if (probe_kernel_address((bug_insn_t *)pc, insn)) + return 0; + return ((insn & __INSN_LENGTH_MASK) == __INSN_LENGTH_32) ? 4UL : 2UL; +} +#endif /* CONFIG_GENERIC_BUG */ + asmlinkage void do_trap_break(struct pt_regs *regs) { #ifdef CONFIG_GENERIC_BUG @@ -129,7 +140,8 @@ asmlinkage void do_trap_break(struct pt_regs *regs) case BUG_TRAP_TYPE_NONE: break; case BUG_TRAP_TYPE_WARN: - die(regs, "Kernel BUG. Kernel got an unexpected WARN trapped by ebreak"); + regs->sepc += get_break_insn_length(regs->sepc); + break; case BUG_TRAP_TYPE_BUG: die(regs, "Kernel BUG"); } @@ -149,12 +161,13 @@ int is_valid_bugaddr(unsigned long pc) if (probe_kernel_address((bug_insn_t *)pc, insn)) return 0; if ((insn & __INSN_LENGTH_MASK) == __INSN_LENGTH_32) - return insn == __BUG_INSN_32; + return (insn == __BUG_INSN_32); else - return (insn & __COMPRESSED_INSN_MASK) == __BUG_INSN_16; + return ((insn & __COMPRESSED_INSN_MASK) == __BUG_INSN_16); } #endif /* CONFIG_GENERIC_BUG */ + void __init trap_init(void) { /*