kernel.git/drivers/net/ethernet/cisco, branch linux-4.4.y

net: enic: Cure the enic api locking trainwreck

2020-10-29T08:03:04Z

[ Upstream commit a53b59ece86c86d16d12ccdaa1ad0c78250a9d96 ] enic_dev_wait() has a BUG_ON(in_interrupt()). Chasing the callers of enic_dev_wait() revealed the gems of enic_reset() and enic_tx_hang_reset() which are both invoked through work queues in order to be able to call rtnl_lock(). So far so good. After locking rtnl both functions acquire enic::enic_api_lock which serializes against the (ab)use from infiniband. This is where the trainwreck starts. enic::enic_api_lock is a spin_lock() which implicitly disables preemption, but both functions invoke a ton of functions under that lock which can sleep. The BUG_ON(in_interrupt()) does not trigger in that case because it can't detect the preempt disabled condition. This clearly has never been tested with any of the mandatory debug options for 7+ years, which would have caught that for sure. Cure it by adding a enic_api_busy member to struct enic, which is modified and evaluated with enic::enic_api_lock held. If enic_api_devcmd_proxy_by_index() observes enic::enic_api_busy as true, it drops enic::enic_api_lock and busy waits for enic::enic_api_busy to become false. It would be smarter to wait for a completion of that busy period, but enic_api_devcmd_proxy_by_index() is called with other spin locks held which obviously can't sleep. Remove the BUG_ON(in_interrupt()) check as well because it's incomplete and with proper debugging enabled the problem would have been caught from the debug checks in schedule_timeout(). Fixes: 0b038566c0ea ("drivers/net: enic: Add an interface for USNIC to interact with firmware") Signed-off-by: Thomas Gleixner Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

enic: do not overwrite error code

2020-05-20T06:11:31Z

commit 56f772279a762984f6e9ebbf24a7c829faba5712 upstream. In failure path, we overwrite err to what vnic_rq_disable() returns. In case it returns 0, enic_open() returns success in case of error. Reported-by: Ben Hutchings Fixes: e8588e268509 ("enic: enable rq before updating rq descriptors") Signed-off-by: Govindarajulu Varadarajan Signed-off-by: David S. Miller Cc: Guenter Roeck Signed-off-by: Greg Kroah-Hartman

enic: prevent waking up stopped tx queues over watchdog reset

2020-02-28T14:39:11Z

[ Upstream commit 0f90522591fd09dd201065c53ebefdfe3c6b55cb ] Recent months, our customer reported several kernel crashes all preceding with following message: NETDEV WATCHDOG: eth2 (enic): transmit queue 0 timed out Error message of one of those crashes: BUG: unable to handle kernel paging request at ffffffffa007e090 After analyzing severl vmcores, I found that most of crashes are caused by memory corruption. And all the corrupted memory areas are overwritten by data of network packets. Moreover, I also found that the tx queues were enabled over watchdog reset. After going through the source code, I found that in enic_stop(), the tx queues stopped by netif_tx_disable() could be woken up over a small time window between netif_tx_disable() and the napi_disable() by the following code path: napi_poll-> enic_poll_msix_wq-> vnic_cq_service-> enic_wq_service-> netif_wake_subqueue(enic->netdev, q_number)-> test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &txq->state) In turn, upper netowrk stack could queue skb to ENIC NIC though enic_hard_start_xmit(). And this might introduce some race condition. Our customer comfirmed that this kind of kernel crash doesn't occur over 90 days since they applied this patch. Signed-off-by: Firo Yang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

enic: fix build warning without CONFIG_CPUMASK_OFFSTACK

2019-04-27T07:33:48Z

[ Upstream commit 43d281662fdb46750d49417559b71069f435298d ] The enic driver relies on the CONFIG_CPUMASK_OFFSTACK feature to dynamically allocate a struct member, but this is normally intended for local variables. Building with clang, I get a warning for a few locations that check the address of the cpumask_var_t: drivers/net/ethernet/cisco/enic/enic_main.c:122:22: error: address of array 'enic->msix[i].affinity_mask' will always evaluate to 'true' [-Werror,-Wpointer-bool-conversion] As far as I can tell, the code is still correct, as the truth value of the pointer is what we need in this configuration. To get rid of the warning, use cpumask_available() instead of checking the pointer directly. Fixes: 322cf7e3a4e8 ("enic: assign affinity hint to interrupts") Signed-off-by: Arnd Bergmann Reviewed-by: Nathan Chancellor Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

enic: fix checksum validation for IPv6

2019-02-20T09:13:15Z

[ Upstream commit 7596175e99b3d4bce28022193efd954c201a782a ] In case of IPv6 pkts, ipv4_csum_ok is 0. Because of this, driver does not set skb->ip_summed. So IPv6 rx checksum is not offloaded. Signed-off-by: Govindarajulu Varadarajan Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

enic: do not call enic_change_mtu in enic_probe

2018-09-15T07:40:40Z

commit cb5c6568867325f9905e80c96531d963bec8e5ea upstream. In commit ab123fe071c9 ("enic: handle mtu change for vf properly") ASSERT_RTNL() is added to _enic_change_mtu() to prevent it from being called without rtnl held. enic_probe() calls enic_change_mtu() without rtnl held. At this point netdev is not registered yet. Remove call to enic_change_mtu and assign the mtu to netdev->mtu. Fixes: ab123fe071c9 ("enic: handle mtu change for vf properly") Signed-off-by: Govindarajulu Varadarajan Signed-off-by: David S. Miller Cc: Ben Hutchings Signed-off-by: Greg Kroah-Hartman

enic: handle mtu change for vf properly

2018-09-05T07:18:36Z

[ Upstream commit ab123fe071c9aa9680ecd62eb080eb26cff4892c ] When driver gets notification for mtu change, driver does not handle it for all RQs. It handles only RQ[0]. Fix is to use enic_change_mtu() interface to change mtu for vf. Signed-off-by: Govindarajulu Varadarajan Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

enic: initialize enic->rfs_h.lock in enic_probe

2018-08-24T11:26:55Z

[ Upstream commit 3256d29fc7aecdf99feb1cb9475ed2252769a8a7 ] lockdep spotted that we are using rfs_h.lock in enic_get_rxnfc() without initializing. rfs_h.lock is initialized in enic_open(). But ethtool_ops can be called when interface is down. Move enic_rfs_flw_tbl_init to enic_probe. INFO: trying to register non-static key. the code is fine but needs lockdep annotation. turning off the locking correctness validator. CPU: 18 PID: 1189 Comm: ethtool Not tainted 4.17.0-rc7-devel+ #27 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014 Call Trace: dump_stack+0x85/0xc0 register_lock_class+0x550/0x560 ? __handle_mm_fault+0xa8b/0x1100 __lock_acquire+0x81/0x670 lock_acquire+0xb9/0x1e0 ? enic_get_rxnfc+0x139/0x2b0 [enic] _raw_spin_lock_bh+0x38/0x80 ? enic_get_rxnfc+0x139/0x2b0 [enic] enic_get_rxnfc+0x139/0x2b0 [enic] ethtool_get_rxnfc+0x8d/0x1c0 dev_ethtool+0x16c8/0x2400 ? __mutex_lock+0x64d/0xa00 ? dev_load+0x6a/0x150 dev_ioctl+0x253/0x4b0 sock_do_ioctl+0x9a/0x130 sock_ioctl+0x1af/0x350 do_vfs_ioctl+0x8e/0x670 ? syscall_trace_enter+0x1e2/0x380 ksys_ioctl+0x60/0x90 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x5a/0x170 entry_SYSCALL_64_after_hwframe+0x49/0xbe Signed-off-by: Govindarajulu Varadarajan Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

enic: set DMA mask to 47 bit

2018-06-13T14:15:28Z

[ Upstream commit 322eaa06d55ebc1402a4a8d140945cff536638b4 ] In commit 624dbf55a359b ("driver/net: enic: Try DMA 64 first, then failover to DMA") DMA mask was changed from 40 bits to 64 bits. Hardware actually supports only 47 bits. Fixes: 624dbf55a359b ("driver/net: enic: Try DMA 64 first, then failover to DMA") Signed-off-by: Govindarajulu Varadarajan Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

enic: enable rq before updating rq descriptors

2018-05-30T05:49:14Z

[ Upstream commit e8588e268509292550634d9a35f2723a207683b2 ] rq should be enabled before posting the buffers to rq desc. If not hw sees stale value and casuses DMAR errors. Signed-off-by: Govindarajulu Varadarajan Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman