From 4fc5461823c9cad547a9bdfbf17d13f0da0d6bb5 Mon Sep 17 00:00:00 2001
From: Shay Drory <shayd@nvidia.com>
Date: Mon, 25 Jan 2021 14:13:38 +0200
Subject: [PATCH 1/1] IB/umad: Return EIO in case of when device disassociated
Git-commit: 4fc5461823c9cad547a9bdfbf17d13f0da0d6bb5
Patch-mainline: v5.12
References: git-fixes

MAD message received by the user has EINVAL error in all flows
including when the device is disassociated. That makes it impossible
for the applications to treat such flow differently.

Change it to return EIO, so the applications will be able to perform
disassociation recovery.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Link: https://lore.kernel.org/r/20210125121339.837518-2-leon@kernel.org
Signed-off-by: Shay Drory <shayd@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Nicolas Morey-Chaisemartin <nmoreychaisemartin@suse.com>
---
 drivers/infiniband/core/user_mad.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/infiniband/core/user_mad.c b/drivers/infiniband/core/user_mad.c
index 19104a675691..7ec1918431f7 100644
--- a/drivers/infiniband/core/user_mad.c
+++ b/drivers/infiniband/core/user_mad.c
@@ -379,6 +379,11 @@ static ssize_t ib_umad_read(struct file *filp, char __user *buf,
 
 	mutex_lock(&file->mutex);
 
+	if (file->agents_dead) {
+		mutex_unlock(&file->mutex);
+		return -EIO;
+	}
+
 	while (list_empty(&file->recv_list)) {
 		mutex_unlock(&file->mutex);
 
@@ -524,7 +529,7 @@ static ssize_t ib_umad_write(struct file *filp, const char __user *buf,
 
 	agent = __get_agent(file, packet->mad.hdr.id);
 	if (!agent) {
-		ret = -EINVAL;
+		ret = -EIO;
 		goto err_up;
 	}
 
-- 
2.31.1.5.g533053588dc3