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From 1f45dc22066797479072978feeada0852502e180 Mon Sep 17 00:00:00 2001
From: Lijun Pan <ljp@linux.ibm.com>
Date: Wed, 23 Dec 2020 14:49:04 -0600
Subject: [PATCH] ibmvnic: continue fatal error reset after passive init

References: bsc#1171078 ltc#184239 git-fixes
Patch-mainline: v5.11 or v5.11-rc3 (next release)
Git-commit: 1f45dc22066797479072978feeada0852502e180

Commit f9c6cea0b385 ("ibmvnic: Skip fatal error reset after passive init")
says "If the passive
CRQ initialization occurs before the FATAL reset task is processed,
the FATAL error reset task would try to access a CRQ message queue
that was freed, causing an oops. The problem may be most likely to
occur during DLPAR add vNIC with a non-default MTU, because the DLPAR
process will automatically issue a change MTU request.
Fix this by not processing fatal error reset if CRQ is passively
initialized after client-driven CRQ initialization fails."

The original commit skips a specific reset condition, but that does
not fix the problem it claims to fix, and misses a reset condition.
The effective fix is commit 0e435befaea4 ("ibmvnic: fix NULL pointer
dereference in ibmvic_reset_crq") and commit a0faaa27c716 ("ibmvnic:
fix NULL pointer dereference in reset_sub_crq_queues"). With above
two fixes, there are no more crashes seen as described even without
the original commit, so I would like to revert the original commit.

Fixes: f9c6cea0b385 ("ibmvnic: Skip fatal error reset after passive init")
Signed-off-by: Lijun Pan <ljp@linux.ibm.com>
Link: https://lore.kernel.org/r/20201223204904.12677-1-ljp@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
 drivers/net/ethernet/ibm/ibmvnic.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index bd0281020d51..91ebcde30292 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -2342,8 +2342,7 @@ static void __ibmvnic_reset(struct work_struct *work)
 				set_current_state(TASK_UNINTERRUPTIBLE);
 				schedule_timeout(60 * HZ);
 			}
-		} else if (!(rwi->reset_reason == VNIC_RESET_FATAL &&
-				adapter->from_passive_init)) {
+		} else {
 			rc = do_reset(adapter, rwi, reset_state);
 		}
 		kfree(rwi);
-- 
2.26.2