From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 517CBC2B9F8 for ; Tue, 25 May 2021 18:49:59 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 15F906140E for ; Tue, 25 May 2021 18:49:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 15F906140E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:List-Subscribe:List-Help: List-Post:List-Archive:List-Unsubscribe:List-Id:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=DaKQb2qSVIB3ofv9KlMcbxvQprGUdkert24HkKevqHU=; b=caA68+lN6ad1LT 3y7PwZUHCOLNMSAMkJfats+LKVQBC1ds7SZlXUiP9PzhX8srmujHfj5AWxJHHZiIGOKw2mddpDBfP 65X4OIcWomxgXdvv19/SoDkYuBL+aseYILRFssib1n5jhTkka2xSspiWIta/6QBXGl8leOKFeqJ+I n0s2IdT+RzW052j6i5xLRT3lFYek0mx4YlYR043C17Q8ll7W82U3Ga8UsVqzvUqq7ajpiobGkZ1XX NfGDd8DGLWnLhbVunr+HKWJr3JOgHE6WwBp8bgv8QzdZFpjs4djpoVraQpTAmnk02krHIQld5JJFj IwlbwdiC5AKKdRQJ9ezA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1llc5l-007Pde-Hz; Tue, 25 May 2021 18:47:50 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1llbsz-007IWZ-0g for linux-arm-kernel@lists.infradead.org; Tue, 25 May 2021 18:34:38 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A0493168F; Tue, 25 May 2021 11:34:35 -0700 (PDT) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 9807A3F719; Tue, 25 May 2021 11:34:34 -0700 (PDT) From: Mark Rutland To: linux-arm-kernel@lists.infradead.org Cc: catalin.marinas@arm.com, james.morse@arm.com, joey.gouly@arm.com, mark.rutland@arm.com, maz@kernel.org, will@kernel.org Subject: [PATCH v3 12/20] arm64: entry: improve bad_mode() Date: Tue, 25 May 2021 19:32:54 +0100 Message-Id: <20210525183302.56293-13-mark.rutland@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20210525183302.56293-1-mark.rutland@arm.com> References: <20210525183302.56293-1-mark.rutland@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210525_113437_175877_39C596D0 X-CRM114-Status: GOOD ( 14.20 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Our use of bad_mode() has a few rough edges: * AArch64 doesn't use the term "mode", and refers to "Execution states", "Exception levels", and "Selected stack pointer". * We log the exception type (SYNC/IRQ/FIQ/SError), but not the actual "mode" (though this can be decoded from the SPSR value). * We use bad_mode() as a second-level handler for unexpected synchronous exceptions, where the "mode" is legitimate, but the specific exception is not. * We dump the ESR value, but call this "code", and so it's not clear to all readers that this is the ESR. ... and all of this can be somewhat opaque to those who aren't extremely familiar with the code. Let's make this a bit clearer by having bad_mode() log "Unhandled ${TYPE} exception" rather than "Bad mode in ${TYPE} handler", using "ESR" rather than "code", and having the final panic() log "Unhandled exception" rather than "Bad mode". In future we'd like to log the specific architectural vector rather than just the type of exception, so we also split the core of bad_mode() out into a helper called __panic_unhandled(), which takes the vector as a string argument. Signed-off-by: Mark Rutland Reviewed-by: Joey Gouly Cc: Catalin Marinas Cc: James Morse Cc: Marc Zyngier Cc: Will Deacon --- arch/arm64/kernel/entry-common.c | 31 ++++++++++++++++--------------- 1 file changed, 16 insertions(+), 15 deletions(-) diff --git a/arch/arm64/kernel/entry-common.c b/arch/arm64/kernel/entry-common.c index 25531a0b547e..b43ef1a918a4 100644 --- a/arch/arm64/kernel/entry-common.c +++ b/arch/arm64/kernel/entry-common.c @@ -160,31 +160,32 @@ static void do_interrupt_handler(struct pt_regs *regs, extern void (*handle_arch_irq)(struct pt_regs *); extern void (*handle_arch_fiq)(struct pt_regs *); -/* - * bad_mode handles the impossible case in the exception vector. This is always - * fatal. - */ -asmlinkage void noinstr bad_mode(struct pt_regs *regs, int reason, unsigned int esr) +static void noinstr __panic_unhandled(struct pt_regs *regs, const char *vector, + unsigned int esr) { - const char *handler[] = { - "Synchronous Abort", - "IRQ", - "FIQ", - "Error" - }; - arm64_enter_nmi(regs); console_verbose(); - pr_crit("Bad mode in %s handler detected on CPU%d, code 0x%08x -- %s\n", - handler[reason], smp_processor_id(), esr, + pr_crit("Unhandled %s exception on CPU%d, ESR 0x%08x -- %s\n", + vector, smp_processor_id(), esr, esr_get_class_string(esr)); __show_regs(regs); - panic("bad mode"); + panic("Unhandled exception"); } +asmlinkage void noinstr bad_mode(struct pt_regs *regs, int reason, unsigned int esr) +{ + const char *handler[] = { + "Synchronous Abort", + "IRQ", + "FIQ", + "Error" + }; + + __panic_unhandled(regs, handler[reason], esr); +} #ifdef CONFIG_ARM64_ERRATUM_1463225 static DEFINE_PER_CPU(int, __in_cortex_a76_erratum_1463225_wa); -- 2.11.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel