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

[<gregkh@linuxfoundation.org>]

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 <stable@vger.kernel.org> know about it.


>From foo@baz Thu Mar  8 06:55:02 PST 2018
From: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Date: Tue, 27 Feb 2018 18:58:13 +0100
Subject: s390/qeth: fix IP removal on offline cards

From: Julian Wiedmann <jwi@linux.vnet.ibm.com>


[ 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.

Fixes: 5f78e29ceebf ("qeth: optimize IP handling in rx_mode callback")
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/s390/net/qeth_l3_main.c |   14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -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 jwi@linux.vnet.ibm.com 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