From patchwork Thu Mar 22 18:14:45 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Morse X-Patchwork-Id: 10302113 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id B6F09600F6 for ; Thu, 22 Mar 2018 18:21:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A7DBA28922 for ; Thu, 22 Mar 2018 18:21:48 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9639328931; Thu, 22 Mar 2018 18:21:48 +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=-1.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID autolearn=unavailable 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 1A4A9288FE for ; Thu, 22 Mar 2018 18:21:47 +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:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: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=dPeygnD4Ddi8W5VWWRDE4kyFwgMYaUR2kgEFaLO9+Yw=; b=YPtqqJE+gOHzjvWByjFmCc+HGv QsGk0hfTEN4VgrXM572Ar/ygBD27eWGXpXxehPTnXELHJXP9G2HsH4LTcE86Ekem8WYGCA5i2vQpY oRYWJ4Fa4XouzpoICzZOe9p/n/w1OfBdJOqxp6yhRq+ZBP/C8LD1acLc4/atOx8c/ru6JRXj6AUnX 80b/2Ubkt63mD60tyhWYB6mqnvr4vvFHbbpFLrksP19cUJLq52sd63TvPfkzhkvRxHq94DYUryNMc YEE7Z4iXyrzaeK0fMUTR0chNiw29nYTRmmKZ8Qh7xSjbAdpUYRVyQ1mGgUsFsSYK+abf449hrN7Tm xaVC73cA==; 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 1ez4qM-0007c9-Aw; Thu, 22 Mar 2018 18:21:42 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1ez4n6-0004H7-0W for linux-arm-kernel@lists.infradead.org; Thu, 22 Mar 2018 18:18:29 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E8DB81993; Thu, 22 Mar 2018 11:18:19 -0700 (PDT) Received: from melchizedek.cambridge.arm.com (melchizedek.cambridge.arm.com [10.1.207.55]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 056F23F487; Thu, 22 Mar 2018 11:18:16 -0700 (PDT) From: James Morse To: linux-acpi@vger.kernel.org Subject: [PATCH v2 11/11] arm64: acpi: Make apei_claim_sea() synchronise with APEI's irq work Date: Thu, 22 Mar 2018 18:14:45 +0000 Message-Id: <20180322181445.23298-12-james.morse@arm.com> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180322181445.23298-1-james.morse@arm.com> References: <20180322181445.23298-1-james.morse@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20180322_111820_747030_37A4516C X-CRM114-Status: GOOD ( 17.29 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Rafael Wysocki , Tony Luck , Christoffer Dall , Punit Agrawal , Xie XiuQi , Marc Zyngier , Catalin Marinas , Tyler Baicar , Will Deacon , Dongjiu Geng , linux-mm@kvack.org, Borislav Petkov , James Morse , Naoya Horiguchi , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Len Brown MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP APEI is unable to do all of its error handling work in nmi-context, so it defers non-fatal work onto the irq_work queue. arch_irq_work_raise() sends an IPI to the calling cpu, but we can't guarantee this will be taken before we return. Unless we interrupted a context with irqs-masked, we can call irq_work_run() to do the work now. Otherwise return -EINPROGRESS to indicate ghes_notify_sea() found some work to do, but it hasn't finished yet. With this we can take apei_claim_sea() returning '0' to mean this external-abort was also notification of a firmware-first RAS error, and that APEI has processed the CPER records. Signed-off-by: James Morse Reviewed-by: Punit Agrawal CC: Xie XiuQi CC: gengdongjiu --- arch/arm64/kernel/acpi.c | 19 +++++++++++++++++++ arch/arm64/mm/fault.c | 9 ++++----- 2 files changed, 23 insertions(+), 5 deletions(-) diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index 6a4823a3eb5e..a51a7abd98e0 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #include #include @@ -275,10 +276,14 @@ int apei_claim_sea(struct pt_regs *regs) { int err = -ENOENT; unsigned long current_flags = arch_local_save_flags(); + unsigned long interrupted_flags = current_flags; if (!IS_ENABLED(CONFIG_ACPI_APEI_SEA)) return err; + if (regs) + interrupted_flags = regs->pstate; + /* * APEI expects an NMI-like notification to always be called * in NMI context. @@ -287,6 +292,20 @@ int apei_claim_sea(struct pt_regs *regs) nmi_enter(); err = ghes_notify_sea(); nmi_exit(); + + /* + * APEI NMI-like notifications are deferred to irq_work. Unless + * we interrupted irqs-masked code, we can do that now. + */ + if (!err) { + if (!arch_irqs_disabled_flags(interrupted_flags)) { + local_daif_restore(DAIF_PROCCTX_NOIRQ); + irq_work_run(); + } else { + err = -EINPROGRESS; + } + } + local_daif_restore(current_flags); return err; diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 303c8b425c82..e218e291a17a 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -580,11 +580,10 @@ static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs) inf->name, esr, addr); if (IS_ENABLED(CONFIG_ACPI_APEI_SEA)) { - /* - * Return value ignored as we rely on signal merging. - * Future patches will make this more robust. - */ - apei_claim_sea(regs); + if (apei_claim_sea(regs) == 0) { + /* APEI claimed this as a firmware-first notification */ + return 0; + } } info.si_signo = SIGBUS;