| Message ID | 20240206085849.2902775-1-wintera@linux.ibm.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 2fe8a236436fe40d8d26a1af8d150fc80f04ee1a |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net] s390/qeth: Fix potential loss of L3-IP@ in case of network issues | expand |
Hello: This patch was applied to netdev/net.git (main) by Paolo Abeni <pabeni@redhat.com>: On Tue, 6 Feb 2024 09:58:49 +0100 you wrote: > Symptom: > In case of a bad cable connection (e.g. dirty optics) a fast sequence of > network DOWN-UP-DOWN-UP could happen. UP triggers recovery of the qeth > interface. In case of a second DOWN while recovery is still ongoing, it > can happen that the IP@ of a Layer3 qeth interface is lost and will not > be recovered by the second UP. > > [...] Here is the summary with links: - [net] s390/qeth: Fix potential loss of L3-IP@ in case of network issues https://git.kernel.org/netdev/net/c/2fe8a236436f You are awesome, thank you!
diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c index b92a32b4b114..04c64ce0a1ca 100644 --- a/drivers/s390/net/qeth_l3_main.c +++ b/drivers/s390/net/qeth_l3_main.c @@ -255,9 +255,10 @@ static void qeth_l3_clear_ip_htable(struct qeth_card *card, int recover) if (!recover) { hash_del(&addr->hnode); kfree(addr); - continue; + } else { + /* prepare for recovery */ + addr->disp_flag = QETH_DISP_ADDR_ADD; } - addr->disp_flag = QETH_DISP_ADDR_ADD; } mutex_unlock(&card->ip_lock); @@ -278,9 +279,11 @@ static void qeth_l3_recover_ip(struct qeth_card *card) if (addr->disp_flag == QETH_DISP_ADDR_ADD) { rc = qeth_l3_register_addr_entry(card, addr); - if (!rc) { + if (!rc || rc == -EADDRINUSE || rc == -ENETDOWN) { + /* keep it in the records */ addr->disp_flag = QETH_DISP_ADDR_DO_NOTHING; } else { + /* bad address */ hash_del(&addr->hnode); kfree(addr); }
Symptom: In case of a bad cable connection (e.g. dirty optics) a fast sequence of network DOWN-UP-DOWN-UP could happen. UP triggers recovery of the qeth interface. In case of a second DOWN while recovery is still ongoing, it can happen that the IP@ of a Layer3 qeth interface is lost and will not be recovered by the second UP. Problem: When registration of IP addresses with Layer 3 qeth devices fails, (e.g. because of bad address format) the respective IP address is deleted from its hash-table in the driver. If registration fails because of a ENETDOWN condition, the address should stay in the hashtable, so a subsequent recovery can restore it. 3caa4af834df ("qeth: keep ip-address after LAN_OFFLINE failure") fixes this for registration failures during normal operation, but not during recovery. Solution: Keep L3-IP address in case of ENETDOWN in qeth_l3_recover_ip(). For consistency with qeth_l3_add_ip() we also keep it in case of EADDRINUSE, i.e. for some reason the card already/still has this address registered. Fixes: 4a71df50047f ("qeth: new qeth device driver") Cc: stable@vger.kernel.org Signed-off-by: Alexandra Winter <wintera@linux.ibm.com> --- drivers/s390/net/qeth_l3_main.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)