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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 86819C25B07 for ; Tue, 9 Aug 2022 18:08:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343572AbiHISIS (ORCPT ); Tue, 9 Aug 2022 14:08:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43738 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344847AbiHISHd (ORCPT ); Tue, 9 Aug 2022 14:07:33 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BD9EF286FD; Tue, 9 Aug 2022 11:03:15 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id D4240B8171C; Tue, 9 Aug 2022 18:03:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 22CC6C433B5; Tue, 9 Aug 2022 18:03:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1660068192; bh=aS6kC7/UR/+s4cEQ6IbqOtahiGkvu5P7CX0AzJ/IWIM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=z1rJ4JUnnQU/tn7l9itxmDDqum3h0gn8/ZUB/ARX/biXW9W18qJeniXuKMTilLr7w BpXlk6r3xQD5tBu7hZmE5D5NXkxcKUSRKModiam+Xuvfrb9lznl9VGRveJiRAE3bdh wzz7eZkp7qOMHJB3MhuouNZ54ItfdHMjA4/wuqNw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tony Luck , "Rafael J. Wysocki" Subject: [PATCH 5.4 04/15] ACPI: APEI: Better fix to avoid spamming the console with old error logs Date: Tue, 9 Aug 2022 20:00:22 +0200 Message-Id: <20220809175510.451207033@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220809175510.312431319@linuxfoundation.org> References: <20220809175510.312431319@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tony Luck commit c3481b6b75b4797657838f44028fd28226ab48e0 upstream. The fix in commit 3f8dec116210 ("ACPI/APEI: Limit printable size of BERT table data") does not work as intended on systems where the BIOS has a fixed size block of memory for the BERT table, relying on s/w to quit when it finds a record with estatus->block_status == 0. On these systems all errors are suppressed because the check: if (region_len < ACPI_BERT_PRINT_MAX_LEN) always fails. New scheme skips individual CPER records that are too large, and also limits the total number of records that will be printed to 5. Fixes: 3f8dec116210 ("ACPI/APEI: Limit printable size of BERT table data") Cc: All applicable Signed-off-by: Tony Luck Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/acpi/apei/bert.c | 31 +++++++++++++++++++++++-------- 1 file changed, 23 insertions(+), 8 deletions(-) --- a/drivers/acpi/apei/bert.c +++ b/drivers/acpi/apei/bert.c @@ -29,16 +29,26 @@ #undef pr_fmt #define pr_fmt(fmt) "BERT: " fmt + +#define ACPI_BERT_PRINT_MAX_RECORDS 5 #define ACPI_BERT_PRINT_MAX_LEN 1024 static int bert_disable; +/* + * Print "all" the error records in the BERT table, but avoid huge spam to + * the console if the BIOS included oversize records, or too many records. + * Skipping some records here does not lose anything because the full + * data is available to user tools in: + * /sys/firmware/acpi/tables/data/BERT + */ static void __init bert_print_all(struct acpi_bert_region *region, unsigned int region_len) { struct acpi_hest_generic_status *estatus = (struct acpi_hest_generic_status *)region; int remain = region_len; + int printed = 0, skipped = 0; u32 estatus_len; while (remain >= sizeof(struct acpi_bert_region)) { @@ -46,24 +56,26 @@ static void __init bert_print_all(struct if (remain < estatus_len) { pr_err(FW_BUG "Truncated status block (length: %u).\n", estatus_len); - return; + break; } /* No more error records. */ if (!estatus->block_status) - return; + break; if (cper_estatus_check(estatus)) { pr_err(FW_BUG "Invalid error record.\n"); - return; + break; } - pr_info_once("Error records from previous boot:\n"); - if (region_len < ACPI_BERT_PRINT_MAX_LEN) + if (estatus_len < ACPI_BERT_PRINT_MAX_LEN && + printed < ACPI_BERT_PRINT_MAX_RECORDS) { + pr_info_once("Error records from previous boot:\n"); cper_estatus_print(KERN_INFO HW_ERR, estatus); - else - pr_info_once("Max print length exceeded, table data is available at:\n" - "/sys/firmware/acpi/tables/data/BERT"); + printed++; + } else { + skipped++; + } /* * Because the boot error source is "one-time polled" type, @@ -75,6 +87,9 @@ static void __init bert_print_all(struct estatus = (void *)estatus + estatus_len; remain -= estatus_len; } + + if (skipped) + pr_info(HW_ERR "Skipped %d error records\n", skipped); } static int __init setup_bert_disable(char *str)