[Intel-wired-lan] [PATCH net v2 1/3] iavf: Fix reset error handling

[Intel-wired-lan] [PATCH net v2 1/3] iavf: Fix reset error handling

[Palczewski, Mateusz]

From: Przemyslaw Patynowski <przemyslawx.patynowski@intel.com>

Do not call iavf_close in iavf_reset_task error handling. Doing so can
lead to double call of napi_disable, which can lead to deadlock there.
Removing VF would lead to iavf_remove task being stuck, because it
requires crit_lock, which is held by iavf_close.
Call iavf_disable_vf if reset fail, so that driver will clean up
remaining invalid resources.
During rapid VF resets, HW can fail to setup VF mailbox. Wrong
error handling can lead to iavf_remove being stuck with:
[ 5218.999087] iavf 0000:82:01.0: Failed to init adminq: -53
...
[ 5267.189211] INFO: task repro.sh:11219 blocked for more than 30 seconds.
[ 5267.189520]       Tainted: G S          E     5.18.0-04958-ga54ce3703613-dirty #1
[ 5267.189764] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 5267.190062] task:repro.sh        state:D stack:    0 pid:11219 ppid:  8162 flags:0x00000000
[ 5267.190347] Call Trace:
[ 5267.190647]  <TASK>
[ 5267.190927]  __schedule+0x460/0x9f0
[ 5267.191264]  schedule+0x44/0xb0
[ 5267.191563]  schedule_preempt_disabled+0x14/0x20
[ 5267.191890]  __mutex_lock.isra.12+0x6e3/0xac0
[ 5267.192237]  ? iavf_remove+0xf9/0x6c0 [iavf]
[ 5267.192565]  iavf_remove+0x12a/0x6c0 [iavf]
[ 5267.192911]  ? _raw_spin_unlock_irqrestore+0x1e/0x40
[ 5267.193285]  pci_device_remove+0x36/0xb0
[ 5267.193619]  device_release_driver_internal+0xc1/0x150
[ 5267.193974]  pci_stop_bus_device+0x69/0x90
[ 5267.194361]  pci_stop_and_remove_bus_device+0xe/0x20
[ 5267.194735]  pci_iov_remove_virtfn+0xba/0x120
[ 5267.195130]  sriov_disable+0x2f/0xe0
[ 5267.195506]  ice_free_vfs+0x7d/0x2f0 [ice]
[ 5267.196056]  ? pci_get_device+0x4f/0x70
[ 5267.196496]  ice_sriov_configure+0x78/0x1a0 [ice]
[ 5267.196995]  sriov_numvfs_store+0xfe/0x140
[ 5267.197466]  kernfs_fop_write_iter+0x12e/0x1c0
[ 5267.197918]  new_sync_write+0x10c/0x190
[ 5267.198404]  vfs_write+0x24e/0x2d0
[ 5267.198886]  ksys_write+0x5c/0xd0
[ 5267.199367]  do_syscall_64+0x3a/0x80
[ 5267.199827]  entry_SYSCALL_64_after_hwframe+0x46/0xb0
[ 5267.200317] RIP: 0033:0x7f5b381205c8
[ 5267.200814] RSP: 002b:00007fff8c7e8c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ 5267.201981] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f5b381205c8
[ 5267.202620] RDX: 0000000000000002 RSI: 00005569420ee900 RDI: 0000000000000001
[ 5267.203426] RBP: 00005569420ee900 R08: 000000000000000a R09: 00007f5b38180820
[ 5267.204327] R10: 000000000000000a R11: 0000000000000246 R12: 00007f5b383c06e0
[ 5267.205193] R13: 0000000000000002 R14: 00007f5b383bb880 R15: 0000000000000002
[ 5267.206041]  </TASK>
[ 5267.206970] Kernel panic - not syncing: hung_task: blocked tasks
[ 5267.207809] CPU: 48 PID: 551 Comm: khungtaskd Kdump: loaded Tainted: G S          E     5.18.0-04958-ga54ce3703613-dirty #1
[ 5267.208726] Hardware name: Dell Inc. PowerEdge R730/0WCJNT, BIOS 2.11.0 11/02/2019
[ 5267.209623] Call Trace:
[ 5267.210569]  <TASK>
[ 5267.211480]  dump_stack_lvl+0x33/0x42
[ 5267.212472]  panic+0x107/0x294
[ 5267.213467]  watchdog.cold.8+0xc/0xbb
[ 5267.214413]  ? proc_dohung_task_timeout_secs+0x30/0x30
[ 5267.215511]  kthread+0xf4/0x120
[ 5267.216459]  ? kthread_complete_and_exit+0x20/0x20
[ 5267.217505]  ret_from_fork+0x22/0x30
[ 5267.218459]  </TASK>

Fixes: f0db78928783 ("i40evf: use netdev variable in reset task")
Signed-off-by: Przemyslaw Patynowski <przemyslawx.patynowski@intel.com>
Signed-off-by: Mateusz Palczewski <mateusz.palczewski@intel.com>
---
 v2: Add comment to make code more understandable
---
 drivers/net/ethernet/intel/iavf/iavf_main.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
index 05b01b67210d..14366210a317 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
@@ -2998,12 +2998,18 @@ static void iavf_reset_task(struct work_struct *work)
 
 	return;
 reset_err:
+	if (running) {
+		set_bit(__IAVF_VSI_DOWN, adapter->vsi.state);
+		/* As we enter iavf_disable_vf with __IAVF_RESETTING state set,
+		 * free traffic irqs here, as it is the only remaining resource
+		 */
+		iavf_free_traffic_irqs(adapter);
+	}
+	iavf_disable_vf(adapter);
+
 	mutex_unlock(&adapter->client_lock);
 	mutex_unlock(&adapter->crit_lock);
-	if (running)
-		iavf_change_state(adapter, __IAVF_RUNNING);
 	dev_err(&adapter->pdev->dev, "failed to allocate resources during reinit\n");
-	iavf_close(netdev);
 }
 
 /**
-- 
2.27.0

_______________________________________________
Intel-wired-lan mailing list
Intel-wired-lan@osuosl.org
https://lists.osuosl.org/mailman/listinfo/intel-wired-lan