From patchwork Tue Jan 29 18:48:53 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Morse X-Patchwork-Id: 10786947 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 6397391E for ; Tue, 29 Jan 2019 18:50:30 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4E77E2D553 for ; Tue, 29 Jan 2019 18:50:30 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4C92F2D554; Tue, 29 Jan 2019 18:50:30 +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 8B0B82D697 for ; Tue, 29 Jan 2019 18:50:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726852AbfA2Su3 (ORCPT ); Tue, 29 Jan 2019 13:50:29 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:42314 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727245AbfA2Su3 (ORCPT ); Tue, 29 Jan 2019 13:50:29 -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 6CC841596; Tue, 29 Jan 2019 10:50:28 -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 C01DC3F557; Tue, 29 Jan 2019 10:50:25 -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 17/26] ACPI / APEI: Pass ghes and estatus separately to avoid a later copy Date: Tue, 29 Jan 2019 18:48:53 +0000 Message-Id: <20190129184902.102850-18-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 The NMI-like notifications scribble over ghes->estatus, before copying it somewhere else. If this interrupts the ghes_probe() code calling ghes_proc() on each struct ghes, the data is corrupted. All the NMI-like notifications should use a queued estatus entry from the beginning, instead of the ghes version, then copying it. To do this, break up any use of "ghes->estatus" so that all functions take the estatus as an argument. This patch just moves these ghes->estatus dereferences into separate arguments, no change in behaviour. struct ghes becomes unused in ghes_clear_estatus() as it only wanted ghes->estatus, which we now pass directly. This is removed. Signed-off-by: James Morse --- Changes since v6: * Changed subject * Renamed ghes_estatus to src_estatus, which is a little clearer * Removed struct ghes from ghes_clear_estatus() now that this becomes unused in this patch. * Mangled the commit message to be different --- drivers/acpi/apei/ghes.c | 92 +++++++++++++++++++++------------------- 1 file changed, 49 insertions(+), 43 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index ccad57468ab7..f95db2398dd5 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -293,9 +293,9 @@ static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len, } } -static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr, - enum fixed_addresses fixmap_idx) - +static int ghes_read_estatus(struct ghes *ghes, + struct acpi_hest_generic_status *estatus, + u64 *buf_paddr, enum fixed_addresses fixmap_idx) { struct acpi_hest_generic *g = ghes->generic; u32 len; @@ -312,25 +312,25 @@ static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr, if (!*buf_paddr) return -ENOENT; - ghes_copy_tofrom_phys(ghes->estatus, *buf_paddr, - sizeof(*ghes->estatus), 1, fixmap_idx); - if (!ghes->estatus->block_status) { + ghes_copy_tofrom_phys(estatus, *buf_paddr, sizeof(*estatus), 1, + fixmap_idx); + if (!estatus->block_status) { *buf_paddr = 0; return -ENOENT; } rc = -EIO; - len = cper_estatus_len(ghes->estatus); - if (len < sizeof(*ghes->estatus)) + len = cper_estatus_len(estatus); + if (len < sizeof(*estatus)) goto err_read_block; if (len > ghes->generic->error_block_length) goto err_read_block; - if (cper_estatus_check_header(ghes->estatus)) + if (cper_estatus_check_header(estatus)) goto err_read_block; - ghes_copy_tofrom_phys(ghes->estatus + 1, - *buf_paddr + sizeof(*ghes->estatus), - len - sizeof(*ghes->estatus), 1, fixmap_idx); - if (cper_estatus_check(ghes->estatus)) + ghes_copy_tofrom_phys(estatus + 1, + *buf_paddr + sizeof(*estatus), + len - sizeof(*estatus), 1, fixmap_idx); + if (cper_estatus_check(estatus)) goto err_read_block; rc = 0; @@ -342,16 +342,17 @@ static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr, return rc; } -static void ghes_clear_estatus(struct ghes *ghes, u64 buf_paddr, - enum fixed_addresses fixmap_idx) +static void ghes_clear_estatus(struct ghes *ghes, + struct acpi_hest_generic_status *estatus, + u64 buf_paddr, enum fixed_addresses fixmap_idx) { - ghes->estatus->block_status = 0; + estatus->block_status = 0; if (!buf_paddr) return; - ghes_copy_tofrom_phys(ghes->estatus, buf_paddr, - sizeof(ghes->estatus->block_status), 0, + ghes_copy_tofrom_phys(estatus, buf_paddr, + sizeof(estatus->block_status), 0, fixmap_idx); /* @@ -651,12 +652,13 @@ static void ghes_estatus_cache_add( rcu_read_unlock(); } -static void __ghes_panic(struct ghes *ghes, u64 buf_paddr, - enum fixed_addresses fixmap_idx) +static void __ghes_panic(struct ghes *ghes, + struct acpi_hest_generic_status *estatus, + u64 buf_paddr, enum fixed_addresses fixmap_idx) { - __ghes_print_estatus(KERN_EMERG, ghes->generic, ghes->estatus); + __ghes_print_estatus(KERN_EMERG, ghes->generic, estatus); - ghes_clear_estatus(ghes, buf_paddr, fixmap_idx); + ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx); /* reboot to log the error! */ if (!panic_timeout) @@ -666,25 +668,25 @@ static void __ghes_panic(struct ghes *ghes, u64 buf_paddr, static int ghes_proc(struct ghes *ghes) { + struct acpi_hest_generic_status *estatus = ghes->estatus; u64 buf_paddr; int rc; - rc = ghes_read_estatus(ghes, &buf_paddr, FIX_APEI_GHES_IRQ); + rc = ghes_read_estatus(ghes, estatus, &buf_paddr, FIX_APEI_GHES_IRQ); if (rc) goto out; - if (ghes_severity(ghes->estatus->error_severity) >= GHES_SEV_PANIC) { - __ghes_panic(ghes, buf_paddr, FIX_APEI_GHES_IRQ); - } + if (ghes_severity(estatus->error_severity) >= GHES_SEV_PANIC) + __ghes_panic(ghes, estatus, buf_paddr, FIX_APEI_GHES_IRQ); - if (!ghes_estatus_cached(ghes->estatus)) { - if (ghes_print_estatus(NULL, ghes->generic, ghes->estatus)) - ghes_estatus_cache_add(ghes->generic, ghes->estatus); + if (!ghes_estatus_cached(estatus)) { + if (ghes_print_estatus(NULL, ghes->generic, estatus)) + ghes_estatus_cache_add(ghes->generic, estatus); } - ghes_do_proc(ghes, ghes->estatus); + ghes_do_proc(ghes, estatus); out: - ghes_clear_estatus(ghes, buf_paddr, FIX_APEI_GHES_IRQ); + ghes_clear_estatus(ghes, estatus, buf_paddr, FIX_APEI_GHES_IRQ); return rc; } @@ -825,17 +827,20 @@ static void ghes_print_queued_estatus(void) } /* Save estatus for further processing in IRQ context */ -static void __process_error(struct ghes *ghes) +static void __process_error(struct ghes *ghes, + struct acpi_hest_generic_status *src_estatus) { -#ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG u32 len, node_len; struct ghes_estatus_node *estatus_node; struct acpi_hest_generic_status *estatus; - if (ghes_estatus_cached(ghes->estatus)) + if (!IS_ENABLED(CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG)) return; - len = cper_estatus_len(ghes->estatus); + if (ghes_estatus_cached(src_estatus)) + return; + + len = cper_estatus_len(src_estatus); node_len = GHES_ESTATUS_NODE_LEN(len); estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, node_len); @@ -845,30 +850,31 @@ static void __process_error(struct ghes *ghes) estatus_node->ghes = ghes; estatus_node->generic = ghes->generic; estatus = GHES_ESTATUS_FROM_NODE(estatus_node); - memcpy(estatus, ghes->estatus, len); + memcpy(estatus, src_estatus, len); llist_add(&estatus_node->llnode, &ghes_estatus_llist); -#endif } 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, &buf_paddr, fixmap_idx)) { - ghes_clear_estatus(ghes, buf_paddr, fixmap_idx); + if (ghes_read_estatus(ghes, estatus, &buf_paddr, fixmap_idx)) { + ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx); return -ENOENT; } - sev = ghes_severity(ghes->estatus->error_severity); + sev = ghes_severity(estatus->error_severity); if (sev >= GHES_SEV_PANIC) { ghes_print_queued_estatus(); - __ghes_panic(ghes, buf_paddr, fixmap_idx); + __ghes_panic(ghes, estatus, buf_paddr, fixmap_idx); + } - __process_error(ghes); - ghes_clear_estatus(ghes, buf_paddr, fixmap_idx); + __process_error(ghes, estatus); + ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx); return 0; }