[PATCH AUTOSEL 4.18 74/88] s390/qeth: reset layer2 attribute on layer switch

From: Sasha Levin
Date: Thu Sep 06 2018 - 20:57:00 EST


From: Julian Wiedmann <jwi@xxxxxxxxxxxxx>

[ Upstream commit 70551dc46ffa3555a0b5f3545b0cd87ab67fd002 ]

After the subdriver's remove() routine has completed, the card's layer
mode is undetermined again. Reflect this in the layer2 field.

If qeth_dev_layer2_store() hits an error after remove() was called, the
card _always_ requires a setup(), even if the previous layer mode is
requested again.
But qeth_dev_layer2_store() bails out early if the requested layer mode
still matches the current one. So unless we reset the layer2 field,
re-probing the card back to its previous mode is currently not possible.

Signed-off-by: Julian Wiedmann <jwi@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
drivers/s390/net/qeth_core_sys.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/s390/net/qeth_core_sys.c b/drivers/s390/net/qeth_core_sys.c
index c3f18afb368b..cfb659747693 100644
--- a/drivers/s390/net/qeth_core_sys.c
+++ b/drivers/s390/net/qeth_core_sys.c
@@ -426,6 +426,7 @@ static ssize_t qeth_dev_layer2_store(struct device *dev,
if (card->discipline) {
card->discipline->remove(card->gdev);
qeth_core_free_discipline(card);
+ card->options.layer2 = -1;
}

rc = qeth_core_load_discipline(card, newdis);
--
2.17.1