[PATCH AUTOSEL for 4.14 066/161] i40evf: Don't schedule reset_task when device is being removed

From: Sasha Levin
Date: Sun Apr 08 2018 - 20:23:56 EST


From: Avinash Dayanand <avinash.dayanand@xxxxxxxxx>

[ Upstream commit 06aa040f039404a0039a5158cd12f41187487a1f ]

When a host disables and enables a PF device, all the associated
VFs are removed and added back in. It also generates a PFR which in turn
resets all the connected VFs. This behaviour is different from that of
Linux guest on Linux host. Hence we end up in a situation where there's
a PFR and device removal at the same time. And watchdog doesn't have a
clue about this and schedules a reset_task. This patch adds code to send
signal to reset_task that the device is currently being removed.

Signed-off-by: Avinash Dayanand <avinash.dayanand@xxxxxxxxx>
Tested-by: Andrew Bowers <andrewx.bowers@xxxxxxxxx>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@xxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
drivers/net/ethernet/intel/i40evf/i40evf.h | 1 +
drivers/net/ethernet/intel/i40evf/i40evf_main.c | 9 ++++++++-
2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/i40evf/i40evf.h b/drivers/net/ethernet/intel/i40evf/i40evf.h
index 82f69031e5cd..2ef32ab1dfae 100644
--- a/drivers/net/ethernet/intel/i40evf/i40evf.h
+++ b/drivers/net/ethernet/intel/i40evf/i40evf.h
@@ -186,6 +186,7 @@ enum i40evf_state_t {
enum i40evf_critical_section_t {
__I40EVF_IN_CRITICAL_TASK, /* cannot be interrupted */
__I40EVF_IN_CLIENT_TASK,
+ __I40EVF_IN_REMOVE_TASK, /* device being removed */
};

/* board specific private data structure */
diff --git a/drivers/net/ethernet/intel/i40evf/i40evf_main.c b/drivers/net/ethernet/intel/i40evf/i40evf_main.c
index 1ccad6f30ebf..048c92a1436a 100644
--- a/drivers/net/ethernet/intel/i40evf/i40evf_main.c
+++ b/drivers/net/ethernet/intel/i40evf/i40evf_main.c
@@ -1834,6 +1834,12 @@ static void i40evf_reset_task(struct work_struct *work)
u32 reg_val;
int i = 0, err;

+ /* When device is being removed it doesn't make sense to run the reset
+ * task, just return in such a case.
+ */
+ if (test_bit(__I40EVF_IN_REMOVE_TASK, &adapter->crit_section))
+ return;
+
while (test_and_set_bit(__I40EVF_IN_CLIENT_TASK,
&adapter->crit_section))
usleep_range(500, 1000);
@@ -3008,7 +3014,8 @@ static void i40evf_remove(struct pci_dev *pdev)
struct i40evf_mac_filter *f, *ftmp;
struct i40e_hw *hw = &adapter->hw;
int err;
-
+ /* Indicate we are in remove and not to run reset_task */
+ set_bit(__I40EVF_IN_REMOVE_TASK, &adapter->crit_section);
cancel_delayed_work_sync(&adapter->init_task);
cancel_work_sync(&adapter->reset_task);
cancel_delayed_work_sync(&adapter->client_task);
--
2.15.1