Patch "s390/qeth: fix IP removal on offline cards" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

s390/qeth: fix IP removal on offline cards

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
s390-qeth-fix-ip-removal-on-offline-cards.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Julian Wiedmann <[email protected]>
Date: Tue, 27 Feb 2018 18:58:13 +0100
Subject: s390/qeth: fix IP removal on offline cards

From: Julian Wiedmann <[email protected]>

[ Upstream commit 98d823ab1fbdcb13abc25b420f9bb71bade42056 ]

If the HW is not reachable, then none of the IPs in qeth's internal table has been registered with the HW yet. So when deleting such an IP, there's no need to stage it for deregistration - just drop it from the table.

This fixes the "add-delete-add" scenario on an offline card, where the the second "add" merely increments the IP's use count. But as the IP is still set to DISP_ADDR_DELETE from the previous "delete" step, l3_recover_ip() won't register it with the HW when the card goes online.

---
 drivers/s390/net/qeth_l3_main.c |   14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

@@ -259,12 +259,8 @@ int qeth_l3_delete_ip(struct qeth_card *
 	if (addr->in_progress)
 		return -EINPROGRESS;
 
-	if (!qeth_card_hw_is_reachable(card)) {
-		addr->disp_flag = QETH_DISP_ADDR_DELETE;
-		return 0;
-	}
-
-	rc = qeth_l3_deregister_addr_entry(card, addr);
+	if (qeth_card_hw_is_reachable(card))
+		rc = qeth_l3_deregister_addr_entry(card, addr);
 
 	hash_del(&addr->hnode);
 	kfree(addr);

@@ -406,11 +402,7 @@ static void qeth_l3_recover_ip(struct qe
 	spin_lock_bh(&card->ip_lock);
 
 	hash_for_each_safe(card->ip_htable, i, tmp, addr, hnode) {
-		if (addr->disp_flag == QETH_DISP_ADDR_DELETE) {
-			qeth_l3_deregister_addr_entry(card, addr);
-			hash_del(&addr->hnode);
-			kfree(addr);
-		} else if (addr->disp_flag == QETH_DISP_ADDR_ADD) {
+		if (addr->disp_flag == QETH_DISP_ADDR_ADD) {
 			if (addr->proto == QETH_PROT_IPV4) {
 				addr->in_progress = 1;
 				spin_unlock_bh(&card->ip_lock);

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/s390-qeth-fix-setip-command-handling.patch queue-4.9/s390-qeth-fix-ip-address-lookup-for-l3-devices.patch queue-4.9/s390-qeth-fix-ipa-command-submission-race.patch queue-4.9/s390-qeth-fix-overestimated-count-of-buffer-elements.patch queue-4.9/s390-qeth-fix-double-free-on-ip-add-remove-race.patch queue-4.9/s390-qeth-fix-ip-removal-on-offline-cards.patch queue-4.9/s390-qeth-fix-underestimated-count-of-buffer-elements.patch