From 69cdb7947adb816fc9325b4ec02a6dddd5070b82 Mon Sep 17 00:00:00 2001
From: Junlin Yang <yangjunlin@yulong.com>
Date: Fri, 5 Mar 2021 16:48:39 +0800
Subject: [PATCH] ibmvnic: remove excessive irqsave
References: bsc#1065729
Patch-mainline: v5.12 or v5.12-rc3 (next release)
Git-commit: 69cdb7947adb816fc9325b4ec02a6dddd5070b82
ibmvnic_remove locks multiple spinlocks while disabling interrupts:
spin_lock_irqsave(&adapter->state_lock, flags);
spin_lock_irqsave(&adapter->rwi_lock, flags);
As reported by coccinelle, the second _irqsave() overwrites the value
saved in 'flags' by the first _irqsave(), therefore when the second
_irqrestore() comes,the value in 'flags' is not valid,the value saved
by the first _irqsave() has been lost.
This likely leads to IRQs remaining disabled. So remove the second
_irqsave():
spin_lock_irqsave(&adapter->state_lock, flags);
spin_lock(&adapter->rwi_lock);
Generated by: ./scripts/coccinelle/locks/flags.cocci
./drivers/net/ethernet/ibm/ibmvnic.c:5413:1-18:
ERROR: nested lock+irqsave that reuses flags from line 5404.
Fixes: 4a41c421f367 ("ibmvnic: serialize access to work queue on remove")
Signed-off-by: Junlin Yang <yangjunlin@yulong.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
drivers/net/ethernet/ibm/ibmvnic.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index b6102ccf9b90..161fa95e8768 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -5408,9 +5408,9 @@ static int ibmvnic_remove(struct vio_dev *dev)
* after setting state, so __ibmvnic_reset() which is called
* from the flush_work() below, can make progress.
*/
- spin_lock_irqsave(&adapter->rwi_lock, flags);
+ spin_lock(&adapter->rwi_lock);
adapter->state = VNIC_REMOVING;
- spin_unlock_irqrestore(&adapter->rwi_lock, flags);
+ spin_unlock(&adapter->rwi_lock);
spin_unlock_irqrestore(&adapter->state_lock, flags);
--
2.26.2