[PATCH net 0/2][pull request] Intel Wired LAN Driver Updates 2022-01-31

[PATCH net 0/2][pull request] Intel Wired LAN Driver Updates 2022-01-31

[Tony Nguyen]

This series contains updates to i40e driver only.

Jedrzej fixes a condition check which would cause an error when
resetting bandwidth when DCB is active with one TC.

Karen resolves a null pointer dereference that could occur when removing
the driver while VSI rings are being disabled.

The following are changes since commit 341adeec9adad0874f29a0a1af35638207352a39:
  net/smc: Forward wakeup to smc socket waitqueue after fallback
and are available in the git repository at:
  git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue 40GbE

Jedrzej Jagielski (1):
  i40e: Fix reset bw limit when DCB enabled with 1 TC

Karen Sornek (1):
  i40e: Fix reset path while removing the driver

 drivers/net/ethernet/intel/i40e/i40e.h      |  1 +
 drivers/net/ethernet/intel/i40e/i40e_main.c | 31 +++++++++++++++++++--
 2 files changed, 30 insertions(+), 2 deletions(-)

-- 
2.31.1

[PATCH net 1/2] i40e: Fix reset bw limit when DCB enabled with 1 TC

[Tony Nguyen]

From: Jedrzej Jagielski <jedrzej.jagielski@intel.com>

There was an AQ error I40E_AQ_RC_EINVAL when trying
to reset bw limit as part of bw allocation setup.
This was caused by trying to reset bw limit with
DCB enabled. Bw limit should not be reset when
DCB is enabled. The code was relying on the pf->flags
to check if DCB is enabled but if only 1 TC is available
this flag will not be set even though DCB is enabled.
Add a check for number of TC and if it is 1
don't try to reset bw limit even if pf->flags shows
DCB as disabled.

Fixes: fa38e30ac73f ("i40e: Fix for Tx timeouts when interface is brought up if DCB is enabled")
Suggested-by: Alexander Lobakin <alexandr.lobakin@intel.com> # Flatten the condition
Signed-off-by: Sylwester Dziedziuch <sylwesterx.dziedziuch@intel.com>
Signed-off-by: Jedrzej Jagielski <jedrzej.jagielski@intel.com>
Reviewed-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Tested-by: Imam Hassan Reza Biswas <imam.hassan.reza.biswas@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
---
 drivers/net/ethernet/intel/i40e/i40e_main.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index f70c478dafdb..5cb4dc69fe87 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -5372,7 +5372,15 @@ static int i40e_vsi_configure_bw_alloc(struct i40e_vsi *vsi, u8 enabled_tc,
 	/* There is no need to reset BW when mqprio mode is on.  */
 	if (pf->flags & I40E_FLAG_TC_MQPRIO)
 		return 0;
-	if (!vsi->mqprio_qopt.qopt.hw && !(pf->flags & I40E_FLAG_DCB_ENABLED)) {
+
+	if (!vsi->mqprio_qopt.qopt.hw) {
+		if (pf->flags & I40E_FLAG_DCB_ENABLED)
+			goto skip_reset;
+
+		if (IS_ENABLED(CONFIG_I40E_DCB) &&
+		    i40e_dcb_hw_get_num_tc(&pf->hw) == 1)
+			goto skip_reset;
+
 		ret = i40e_set_bw_limit(vsi, vsi->seid, 0);
 		if (ret)
 			dev_info(&pf->pdev->dev,
@@ -5380,6 +5388,8 @@ static int i40e_vsi_configure_bw_alloc(struct i40e_vsi *vsi, u8 enabled_tc,
 				 vsi->seid);
 		return ret;
 	}
+
+skip_reset:
 	memset(&bw_data, 0, sizeof(bw_data));
 	bw_data.tc_valid_bits = enabled_tc;
 	for (i = 0; i < I40E_MAX_TRAFFIC_CLASS; i++)
-- 
2.31.1

[PATCH net 2/2] i40e: Fix reset path while removing the driver

[Tony Nguyen]

From: Karen Sornek <karen.sornek@intel.com>

Fix the crash in kernel while dereferencing the NULL pointer,
when the driver is unloaded and simultaneously the VSI rings
are being stopped.

The hardware requires 50msec in order to finish RX queues
disable. For this purpose the driver spins in mdelay function
for the operation to be completed.

For example changing number of queues which requires reset would
fail in the following call stack:

1) i40e_prep_for_reset
2) i40e_pf_quiesce_all_vsi
3) i40e_quiesce_vsi
4) i40e_vsi_close
5) i40e_down
6) i40e_vsi_stop_rings
7) i40e_vsi_control_rx -> disable requires the delay of 50msecs
8) continue back in i40e_down function where
   i40e_clean_tx_ring(vsi->tx_rings[i]) is going to crash

When the driver was spinning vsi_release called
i40e_vsi_free_arrays where the vsi->tx_rings resources
were freed and the pointer was set to NULL.

Fixes: 5b6d4a7f20b0 ("i40e: Fix crash during removing i40e driver")
Signed-off-by: Slawomir Laba <slawomirx.laba@intel.com>
Signed-off-by: Sylwester Dziedziuch <sylwesterx.dziedziuch@intel.com>
Signed-off-by: Karen Sornek <karen.sornek@intel.com>
Tested-by: Gurucharan G <gurucharanx.g@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
---
 drivers/net/ethernet/intel/i40e/i40e.h      |  1 +
 drivers/net/ethernet/intel/i40e/i40e_main.c | 19 ++++++++++++++++++-
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index 2e02cc68cd3f..80c5cecaf2b5 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -144,6 +144,7 @@ enum i40e_state_t {
 	__I40E_VIRTCHNL_OP_PENDING,
 	__I40E_RECOVERY_MODE,
 	__I40E_VF_RESETS_DISABLED,	/* disable resets during i40e_remove */
+	__I40E_IN_REMOVE,
 	__I40E_VFS_RELEASING,
 	/* This must be last as it determines the size of the BITMAP */
 	__I40E_STATE_SIZE__,
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 5cb4dc69fe87..0c4b7dfb3b35 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -10863,6 +10863,9 @@ static void i40e_reset_and_rebuild(struct i40e_pf *pf, bool reinit,
 				   bool lock_acquired)
 {
 	int ret;
+
+	if (test_bit(__I40E_IN_REMOVE, pf->state))
+		return;
 	/* Now we wait for GRST to settle out.
 	 * We don't have to delete the VEBs or VSIs from the hw switch
 	 * because the reset will make them disappear.
@@ -12222,6 +12225,8 @@ int i40e_reconfig_rss_queues(struct i40e_pf *pf, int queue_count)
 
 		vsi->req_queue_pairs = queue_count;
 		i40e_prep_for_reset(pf);
+		if (test_bit(__I40E_IN_REMOVE, pf->state))
+			return pf->alloc_rss_size;
 
 		pf->alloc_rss_size = new_rss_size;
 
@@ -13048,6 +13053,10 @@ static int i40e_xdp_setup(struct i40e_vsi *vsi, struct bpf_prog *prog,
 	if (need_reset)
 		i40e_prep_for_reset(pf);
 
+	/* VSI shall be deleted in a moment, just return EINVAL */
+	if (test_bit(__I40E_IN_REMOVE, pf->state))
+		return -EINVAL;
+
 	old_prog = xchg(&vsi->xdp_prog, prog);
 
 	if (need_reset) {
@@ -15938,8 +15947,13 @@ static void i40e_remove(struct pci_dev *pdev)
 	i40e_write_rx_ctl(hw, I40E_PFQF_HENA(0), 0);
 	i40e_write_rx_ctl(hw, I40E_PFQF_HENA(1), 0);
 
-	while (test_bit(__I40E_RESET_RECOVERY_PENDING, pf->state))
+	/* Grab __I40E_RESET_RECOVERY_PENDING and set __I40E_IN_REMOVE
+	 * flags, once they are set, i40e_rebuild should not be called as
+	 * i40e_prep_for_reset always returns early.
+	 */
+	while (test_and_set_bit(__I40E_RESET_RECOVERY_PENDING, pf->state))
 		usleep_range(1000, 2000);
+	set_bit(__I40E_IN_REMOVE, pf->state);
 
 	if (pf->flags & I40E_FLAG_SRIOV_ENABLED) {
 		set_bit(__I40E_VF_RESETS_DISABLED, pf->state);
@@ -16138,6 +16152,9 @@ static void i40e_pci_error_reset_done(struct pci_dev *pdev)
 {
 	struct i40e_pf *pf = pci_get_drvdata(pdev);
 
+	if (test_bit(__I40E_IN_REMOVE, pf->state))
+		return;
+
 	i40e_reset_and_rebuild(pf, false, false);
 }
 
-- 
2.31.1

Re: [PATCH net 0/2][pull request] Intel Wired LAN Driver Updates 2022-01-31

[patchwork-bot+netdevbpf]

Hello:

This series was applied to netdev/net.git (master)
by Tony Nguyen <anthony.l.nguyen@intel.com>:

On Mon, 31 Jan 2022 16:05:20 -0800 you wrote:
> This series contains updates to i40e driver only.
> 
> Jedrzej fixes a condition check which would cause an error when
> resetting bandwidth when DCB is active with one TC.
> 
> Karen resolves a null pointer dereference that could occur when removing
> the driver while VSI rings are being disabled.
> 
> [...]

Here is the summary with links:
  - [net,1/2] i40e: Fix reset bw limit when DCB enabled with 1 TC
    https://git.kernel.org/netdev/net/c/3d2504663c41
  - [net,2/2] i40e: Fix reset path while removing the driver
    https://git.kernel.org/netdev/net/c/6533e558c650

You are awesome, thank you!
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