Le 05/03/2021 à 02:43, angkery a écrit :
From: Junlin Yang <yangjun...@yulong.com>
ibmvnic_remove locks multiple spinlocks while disabling interrupts:
spin_lock_irqsave(&adapter->state_lock, flags);
spin_lock_irqsave(&adapter->rwi_lock, flags);
there is no need for the second irqsave,since interrupts are disabled
at that point, so remove the second irqsave:
The problème is not that there is no need. The problem is a lot more serious:
As reported by coccinella, 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, which is
_THE_ problem really.
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.
Signed-off-by: Junlin Yang <yangjun...@yulong.com>
---
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 2464c8a..a52668d 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -5408,9 +5408,9 @@ static void 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);
