linux-kernel - [PATCH 4.9 068/134] powerpc/pseries/dlpar: handle ibm, configure-connector delay status

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]

Message-Id: <20210301161016.902253440@linuxfoundation.org>
Date:   Mon,  1 Mar 2021 17:12:49 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Nathan Lynch <nathanl@...ux.ibm.com>,
        Tyrel Datwyler <tyreld@...ux.ibm.com>,
        Michael Ellerman <mpe@...erman.id.au>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 4.9 068/134] powerpc/pseries/dlpar: handle ibm, configure-connector delay status

From: Nathan Lynch <nathanl@...ux.ibm.com>

[ Upstream commit 768d70e19ba525debd571b36e6d0ab19956c63d7 ]

dlpar_configure_connector() has two problems in its handling of
ibm,configure-connector's return status:

1. When the status is -2 (busy, call again), we call
   ibm,configure-connector again immediately without checking whether
   to schedule, which can result in monopolizing the CPU.
2. Extended delay status (9900..9905) goes completely unhandled,
   causing the configuration to unnecessarily terminate.

Fix both of these issues by using rtas_busy_delay().

Fixes: ab519a011caa ("powerpc/pseries: Kernel DLPAR Infrastructure")
Signed-off-by: Nathan Lynch <nathanl@...ux.ibm.com>
Reviewed-by: Tyrel Datwyler <tyreld@...ux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@...erman.id.au>
Link: https://lore.kernel.org/r/20210107025900.410369-1-nathanl@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 arch/powerpc/platforms/pseries/dlpar.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
index 5abb8e2239a54..647dbd8514c4f 100644
--- a/arch/powerpc/platforms/pseries/dlpar.c
+++ b/arch/powerpc/platforms/pseries/dlpar.c
@@ -139,7 +139,6 @@ void dlpar_free_cc_nodes(struct device_node *dn)
 #define NEXT_PROPERTY   3
 #define PREV_PARENT     4
 #define MORE_MEMORY     5
-#define CALL_AGAIN	-2
 #define ERR_CFG_USE     -9003
 
 struct device_node *dlpar_configure_connector(__be32 drc_index,
@@ -181,6 +180,9 @@ struct device_node *dlpar_configure_connector(__be32 drc_index,
 
 		spin_unlock(&rtas_data_buf_lock);
 
+		if (rtas_busy_delay(rc))
+			continue;
+
 		switch (rc) {
 		case COMPLETE:
 			break;
@@ -233,9 +235,6 @@ struct device_node *dlpar_configure_connector(__be32 drc_index,
 			parent_path = last_dn->parent->full_name;
 			break;
 
-		case CALL_AGAIN:
-			break;
-
 		case MORE_MEMORY:
 		case ERR_CFG_USE:
 		default:
-- 
2.27.0