From patchwork Tue Jan 29 18:48:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Morse X-Patchwork-Id: 10786959 X-Patchwork-Delegate: rjw@sisk.pl 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 840561399 for ; Tue, 29 Jan 2019 18:50:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 714732D620 for ; Tue, 29 Jan 2019 18:50:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6EF302D650; Tue, 29 Jan 2019 18:50:40 +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=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F28D32D6CF for ; Tue, 29 Jan 2019 18:50:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729202AbfA2Sui (ORCPT ); Tue, 29 Jan 2019 13:50:38 -0500 Received: from foss.arm.com ([217.140.101.70]:42406 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727245AbfA2Sui (ORCPT ); Tue, 29 Jan 2019 13:50:38 -0500 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 2FA8F15AB; Tue, 29 Jan 2019 10:50:37 -0800 (PST) Received: from eglon.cambridge.arm.com (eglon.cambridge.arm.com [10.1.196.105]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 827933F557; Tue, 29 Jan 2019 10:50:34 -0800 (PST) From: James Morse To: linux-acpi@vger.kernel.org Cc: kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, Borislav Petkov , Marc Zyngier , Christoffer Dall , Will Deacon , Catalin Marinas , Naoya Horiguchi , Rafael Wysocki , Len Brown , Tony Luck , Dongjiu Geng , Xie XiuQi , james.morse@arm.com Subject: [PATCH v8 20/26] ACPI / APEI: Only use queued estatus entry during in_nmi_queue_one_entry() Date: Tue, 29 Jan 2019 18:48:56 +0000 Message-Id: <20190129184902.102850-21-james.morse@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190129184902.102850-1-james.morse@arm.com> References: <20190129184902.102850-1-james.morse@arm.com> MIME-Version: 1.0 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Each struct ghes has an worst-case sized buffer for storing the estatus. If an error is being processed by ghes_proc() in process context this buffer will be in use. If the error source then triggers an NMI-like notification, the same buffer will be used by in_nmi_queue_one_entry() to stage the estatus data, before __process_error() copys it into a queued estatus entry. Merge __process_error()s work into in_nmi_queue_one_entry() so that the queued estatus entry is used from the beginning. Use the new ghes_peek_estatus() to know how much memory to allocate from the ghes_estatus_pool before reading the records. Reported-by: Borislav Petkov Signed-off-by: James Morse Reviewed-by: Borislav Petkov Change since v6: * Added a comment explaining the 'ack-error, then goto no_work'. * Added missing esatus-clearing, which is necessary after reading the GAS, --- drivers/acpi/apei/ghes.c | 64 +++++++++++++++++++++++----------------- 1 file changed, 37 insertions(+), 27 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index 12375a82fa03..957c1559ebf5 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -862,57 +862,67 @@ static void ghes_print_queued_estatus(void) } } -/* Save estatus for further processing in IRQ context */ -static void __process_error(struct ghes *ghes, - struct acpi_hest_generic_status *src_estatus) +static int ghes_in_nmi_queue_one_entry(struct ghes *ghes, + enum fixed_addresses fixmap_idx) { - u32 len, node_len; + struct acpi_hest_generic_status *estatus, tmp_header; struct ghes_estatus_node *estatus_node; - struct acpi_hest_generic_status *estatus; + u32 len, node_len; + u64 buf_paddr; + int sev, rc; if (!IS_ENABLED(CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG)) - return; + return -EOPNOTSUPP; - if (ghes_estatus_cached(src_estatus)) - return; + rc = __ghes_peek_estatus(ghes, &tmp_header, &buf_paddr, fixmap_idx); + if (rc) { + ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx); + return rc; + } - len = cper_estatus_len(src_estatus); - node_len = GHES_ESTATUS_NODE_LEN(len); + rc = __ghes_check_estatus(ghes, &tmp_header); + if (rc) { + ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx); + return rc; + } + len = cper_estatus_len(&tmp_header); + node_len = GHES_ESTATUS_NODE_LEN(len); estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, node_len); if (!estatus_node) - return; + return -ENOMEM; estatus_node->ghes = ghes; estatus_node->generic = ghes->generic; estatus = GHES_ESTATUS_FROM_NODE(estatus_node); - memcpy(estatus, src_estatus, len); - llist_add(&estatus_node->llnode, &ghes_estatus_llist); -} -static int ghes_in_nmi_queue_one_entry(struct ghes *ghes, - enum fixed_addresses fixmap_idx) -{ - struct acpi_hest_generic_status *estatus = ghes->estatus; - u64 buf_paddr; - int sev; - - if (ghes_read_estatus(ghes, estatus, &buf_paddr, fixmap_idx)) { + if (__ghes_read_estatus(estatus, buf_paddr, fixmap_idx, len)) { ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx); - return -ENOENT; + rc = -ENOENT; + goto no_work; } sev = ghes_severity(estatus->error_severity); if (sev >= GHES_SEV_PANIC) { ghes_print_queued_estatus(); __ghes_panic(ghes, estatus, buf_paddr, fixmap_idx); - } - __process_error(ghes, estatus); - ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx); + ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx); - return 0; + /* This error has been reported before, don't process it again. */ + if (ghes_estatus_cached(estatus)) + goto no_work; + + llist_add(&estatus_node->llnode, &ghes_estatus_llist); + + return rc; + +no_work: + gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node, + node_len); + + return rc; } static int ghes_in_nmi_spool_from_list(struct list_head *rcu_list,