linux-kernel - [PATCH v3 5/8] EDAC/amd64: Decode syndrome before translating address

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 22 Aug 2019 00:00:00 +0000
From:   "Ghannam, Yazen" <Yazen.Ghannam@....com>
To:     "linux-edac@...r.kernel.org" <linux-edac@...r.kernel.org>
CC:     "Ghannam, Yazen" <Yazen.Ghannam@....com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "bp@...en8.de" <bp@...en8.de>
Subject: [PATCH v3 5/8] EDAC/amd64: Decode syndrome before translating address

From: Yazen Ghannam <yazen.ghannam@....com>

AMD Family 17h systems currently require address translation in order to
report the system address of a DRAM ECC error. This is currently done
before decoding the syndrome information. The syndrome information does
not depend on the address translation, so the proper EDAC csrow/channel
reporting can function without the address. However, the syndrome
information will not be decoded if the address translation fails.

Decode the syndrome information before doing the address translation.
The syndrome information is architecturally defined in MCA_SYND and can
be considered robust. The address translation is system-specific and may
fail on newer systems without proper updates to the translation
algorithm.

Fixes: 713ad54675fd ("EDAC, amd64: Define and register UMC error decode function")
Signed-off-by: Yazen Ghannam <yazen.ghannam@....com>
---
Link:
https://lkml.kernel.org/r/20190709215643.171078-6-Yazen.Ghannam@amd.com

v2->v3:
* No change.

v1->v2:
* No change.

 drivers/edac/amd64_edac.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
index c4f2d7c59b04..de141de7b2e5 100644
--- a/drivers/edac/amd64_edac.c
+++ b/drivers/edac/amd64_edac.c
@@ -2574,13 +2574,6 @@ static void decode_umc_error(int node_id, struct mce *m)
 
 	err.channel = find_umc_channel(m);
 
-	if (umc_normaddr_to_sysaddr(m->addr, pvt->mc_node_id, err.channel, &sys_addr)) {
-		err.err_code = ERR_NORM_ADDR;
-		goto log_error;
-	}
-
-	error_address_to_page_and_offset(sys_addr, &err);
-
 	if (!(m->status & MCI_STATUS_SYNDV)) {
 		err.err_code = ERR_SYND;
 		goto log_error;
@@ -2597,6 +2590,13 @@ static void decode_umc_error(int node_id, struct mce *m)
 
 	err.csrow = m->synd & 0x7;
 
+	if (umc_normaddr_to_sysaddr(m->addr, pvt->mc_node_id, err.channel, &sys_addr)) {
+		err.err_code = ERR_NORM_ADDR;
+		goto log_error;
+	}
+
+	error_address_to_page_and_offset(sys_addr, &err);
+
 log_error:
 	__log_ecc_error(mci, &err, ecc_type);
 }
-- 
2.17.1