From patchwork Sun Dec 29 17:25:37 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 11312315 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BC363138C for ; Sun, 29 Dec 2019 18:02:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9A545207FF for ; Sun, 29 Dec 2019 18:02:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577642575; bh=UZCOrNCSYzLLHQQCAcwBP86yz0fqplT9ITOoRdzBppw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=IXBfO02UCuDzfFuPXn7BfN0ECZym57xWeNCsmDt120oFvAPJSG5EqbVZYNDL+Sj8M IYn7NoLc0FLeFnZVYMEqNICQ8HJnv6u3w+3sA7g/zzHaD2FG2tCYatyQ4IRh5MikOm P88fW7dJnHD+YTyaV4B5qdjCZK39HCmvyqix7Wco= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387725AbfL2SCz (ORCPT ); Sun, 29 Dec 2019 13:02:55 -0500 Received: from mail.kernel.org ([198.145.29.99]:42288 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732674AbfL2RyZ (ORCPT ); Sun, 29 Dec 2019 12:54:25 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 98E4821744; Sun, 29 Dec 2019 17:54:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577642065; bh=UZCOrNCSYzLLHQQCAcwBP86yz0fqplT9ITOoRdzBppw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ySzmk82yG41ouG4TD8ri0a+QryqBBZINeo9cWZBuF1zj09jAEFwqFUoKCXMbwElKe A7c5M1EX50Bi+8yM01ho9eeNVYLhj7sTTc/ku/DS/PSb0KsVjhtkLmZ+sR+/pbYTxM Gz95lwDQ+niMT1dTFQ1CQc95U4VYEBxi79MpMg4A= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, James Morse , Robert Richter , Borislav Petkov , Mauro Carvalho Chehab , "linux-edac@vger.kernel.org" , Tony Luck , Sasha Levin Subject: [PATCH 5.4 284/434] EDAC/ghes: Fix grain calculation Date: Sun, 29 Dec 2019 18:25:37 +0100 Message-Id: <20191229172720.814013410@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20191229172702.393141737@linuxfoundation.org> References: <20191229172702.393141737@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: linux-edac-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-edac@vger.kernel.org From: Robert Richter [ Upstream commit 7088e29e0423d3195e09079b4f849ec4837e5a75 ] The current code to convert a physical address mask to a grain (defined as granularity in bytes) is: e->grain = ~(mem_err->physical_addr_mask & ~PAGE_MASK); This is broken in several ways: 1) It calculates to wrong grain values. E.g., a physical address mask of ~0xfff should give a grain of 0x1000. Without considering PAGE_MASK, there is an off-by-one. Things are worse when also filtering it with ~PAGE_MASK. This will calculate to a grain with the upper bits set. In the example it even calculates to ~0. 2) The grain does not depend on and is unrelated to the kernel's page-size. The page-size only matters when unmapping memory in memory_failure(). Smaller grains are wrongly rounded up to the page-size, on architectures with a configurable page-size (e.g. arm64) this could round up to the even bigger page-size of the hypervisor. Fix this with: e->grain = ~mem_err->physical_addr_mask + 1; The grain_bits are defined as: grain = 1 << grain_bits; Change also the grain_bits calculation accordingly, it is the same formula as in edac_mc.c now and the code can be unified. The value in ->physical_addr_mask coming from firmware is assumed to be contiguous, but this is not sanity-checked. However, in case the mask is non-contiguous, a conversion to grain_bits effectively converts the grain bit mask to a power of 2 by rounding it up. Suggested-by: James Morse Signed-off-by: Robert Richter Signed-off-by: Borislav Petkov Reviewed-by: Mauro Carvalho Chehab Cc: "linux-edac@vger.kernel.org" Cc: Tony Luck Link: https://lkml.kernel.org/r/20191106093239.25517-11-rrichter@marvell.com Signed-off-by: Sasha Levin --- drivers/edac/ghes_edac.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/edac/ghes_edac.c b/drivers/edac/ghes_edac.c index 296e714bf553..523dd56a798c 100644 --- a/drivers/edac/ghes_edac.c +++ b/drivers/edac/ghes_edac.c @@ -231,6 +231,7 @@ void ghes_edac_report_mem_error(int sev, struct cper_sec_mem_err *mem_err) /* Cleans the error report buffer */ memset(e, 0, sizeof (*e)); e->error_count = 1; + e->grain = 1; strcpy(e->label, "unknown label"); e->msg = pvt->msg; e->other_detail = pvt->other_detail; @@ -326,7 +327,7 @@ void ghes_edac_report_mem_error(int sev, struct cper_sec_mem_err *mem_err) /* Error grain */ if (mem_err->validation_bits & CPER_MEM_VALID_PA_MASK) - e->grain = ~(mem_err->physical_addr_mask & ~PAGE_MASK); + e->grain = ~mem_err->physical_addr_mask + 1; /* Memory error location, mapped on e->location */ p = e->location; @@ -442,8 +443,13 @@ void ghes_edac_report_mem_error(int sev, struct cper_sec_mem_err *mem_err) if (p > pvt->other_detail) *(p - 1) = '\0'; + /* Sanity-check driver-supplied grain value. */ + if (WARN_ON_ONCE(!e->grain)) + e->grain = 1; + + grain_bits = fls_long(e->grain - 1); + /* Generate the trace event */ - grain_bits = fls_long(e->grain); snprintf(pvt->detail_location, sizeof(pvt->detail_location), "APEI location: %s %s", e->location, e->other_detail); trace_mc_event(type, e->msg, e->label, e->error_count,