[PATCH net 0/3][pull request] Intel Wired LAN Driver Updates 2021-10-06

[PATCH net 0/3][pull request] Intel Wired LAN Driver Updates 2021-10-06

[Tony Nguyen]

This series contains updates to i40e and iavf drivers.

Jiri Benc expands an error check to prevent infinite loop for i40e.

Sylwester prevents freeing of uninitialized IRQ vector to resolve a
kernel oops for i40e.

Stefan Assmann fixes a double mutex unlock for iavf.

The following are changes since commit a50a0595230d38be15183699f7bbc963bf3d127a:
  dt-bindings: net: dsa: marvell: fix compatible in example
and are available in the git repository at:
  git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue 40GbE

Jiri Benc (1):
  i40e: fix endless loop under rtnl

Stefan Assmann (1):
  iavf: fix double unlock of crit_lock

Sylwester Dziedziuch (1):
  i40e: Fix freeing of uninitialized misc IRQ vector

 drivers/net/ethernet/intel/i40e/i40e_main.c | 5 +++--
 drivers/net/ethernet/intel/iavf/iavf_main.c | 1 -
 2 files changed, 3 insertions(+), 3 deletions(-)

-- 
2.31.1

[PATCH net 1/3] i40e: fix endless loop under rtnl

[Tony Nguyen]

From: Jiri Benc <jbenc@redhat.com>

The loop in i40e_get_capabilities can never end. The problem is that
although i40e_aq_discover_capabilities returns with an error if there's
a firmware problem, the returned error is not checked. There is a check for
pf->hw.aq.asq_last_status but that value is set to I40E_AQ_RC_OK on most
firmware problems.

When i40e_aq_discover_capabilities encounters a firmware problem, it will
encounter the same problem on its next invocation. As the result, the loop
becomes endless. We hit this with I40E_ERR_ADMIN_QUEUE_TIMEOUT but looking
at the code, it can happen with a range of other firmware errors.

I don't know what the correct behavior should be: whether the firmware
should be retried a few times, or whether pf->hw.aq.asq_last_status should
be always set to the encountered firmware error (but then it would be
pointless and can be just replaced by the i40e_aq_discover_capabilities
return value). However, the current behavior with an endless loop under the
rtnl mutex(!) is unacceptable and Intel has not submitted a fix, although we
explained the bug to them 7 months ago.

This may not be the best possible fix but it's better than hanging the whole
system on a firmware bug.

Fixes: 56a62fc86895 ("i40e: init code and hardware support")
Tested-by: Stefan Assmann <sassmann@redhat.com>
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Dave Switzer <david.switzer@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
---
 drivers/net/ethernet/intel/i40e/i40e_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 2f20980dd9a5..b5b984754ec9 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -10113,7 +10113,7 @@ static int i40e_get_capabilities(struct i40e_pf *pf,
 		if (pf->hw.aq.asq_last_status == I40E_AQ_RC_ENOMEM) {
 			/* retry with a larger buffer */
 			buf_len = data_size;
-		} else if (pf->hw.aq.asq_last_status != I40E_AQ_RC_OK) {
+		} else if (pf->hw.aq.asq_last_status != I40E_AQ_RC_OK || err) {
 			dev_info(&pf->pdev->dev,
 				 "capability discovery failed, err %s aq_err %s\n",
 				 i40e_stat_str(&pf->hw, err),
-- 
2.31.1

[PATCH net 2/3] i40e: Fix freeing of uninitialized misc IRQ vector

[Tony Nguyen]

From: Sylwester Dziedziuch <sylwesterx.dziedziuch@intel.com>

When VSI set up failed in i40e_probe() as part of PF switch set up
driver was trying to free misc IRQ vectors in
i40e_clear_interrupt_scheme and produced a kernel Oops:

   Trying to free already-free IRQ 266
   WARNING: CPU: 0 PID: 5 at kernel/irq/manage.c:1731 __free_irq+0x9a/0x300
   Workqueue: events work_for_cpu_fn
   RIP: 0010:__free_irq+0x9a/0x300
   Call Trace:
   ? synchronize_irq+0x3a/0xa0
   free_irq+0x2e/0x60
   i40e_clear_interrupt_scheme+0x53/0x190 [i40e]
   i40e_probe.part.108+0x134b/0x1a40 [i40e]
   ? kmem_cache_alloc+0x158/0x1c0
   ? acpi_ut_update_ref_count.part.1+0x8e/0x345
   ? acpi_ut_update_object_reference+0x15e/0x1e2
   ? strstr+0x21/0x70
   ? irq_get_irq_data+0xa/0x20
   ? mp_check_pin_attr+0x13/0xc0
   ? irq_get_irq_data+0xa/0x20
   ? mp_map_pin_to_irq+0xd3/0x2f0
   ? acpi_register_gsi_ioapic+0x93/0x170
   ? pci_conf1_read+0xa4/0x100
   ? pci_bus_read_config_word+0x49/0x70
   ? do_pci_enable_device+0xcc/0x100
   local_pci_probe+0x41/0x90
   work_for_cpu_fn+0x16/0x20
   process_one_work+0x1a7/0x360
   worker_thread+0x1cf/0x390
   ? create_worker+0x1a0/0x1a0
   kthread+0x112/0x130
   ? kthread_flush_work_fn+0x10/0x10
   ret_from_fork+0x1f/0x40

The problem is that at that point misc IRQ vectors
were not allocated yet and we get a call trace
that driver is trying to free already free IRQ vectors.

Add a check in i40e_clear_interrupt_scheme for __I40E_MISC_IRQ_REQUESTED
PF state before calling i40e_free_misc_vector. This state is set only if
misc IRQ vectors were properly initialized.

Fixes: c17401a1dd21 ("i40e: use separate state bit for miscellaneous IRQ setup")
Reported-by: PJ Waskiewicz <pwaskiewicz@jumptrading.com>
Signed-off-by: Sylwester Dziedziuch <sylwesterx.dziedziuch@intel.com>
Signed-off-by: Mateusz Palczewski <mateusz.palczewski@intel.com>
Tested-by: Dave Switzer <david.switzer@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
---
 drivers/net/ethernet/intel/i40e/i40e_main.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index b5b984754ec9..e04b540cedc8 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -4871,7 +4871,8 @@ static void i40e_clear_interrupt_scheme(struct i40e_pf *pf)
 {
 	int i;
 
-	i40e_free_misc_vector(pf);
+	if (test_bit(__I40E_MISC_IRQ_REQUESTED, pf->state))
+		i40e_free_misc_vector(pf);
 
 	i40e_put_lump(pf->irq_pile, pf->iwarp_base_vector,
 		      I40E_IWARP_IRQ_PILE_ID);
-- 
2.31.1

[PATCH net 3/3] iavf: fix double unlock of crit_lock

[Tony Nguyen]

From: Stefan Assmann <sassmann@kpanic.de>

The crit_lock mutex could be unlocked twice as reported here
https://lists.osuosl.org/pipermail/intel-wired-lan/Week-of-Mon-20210823/025525.html

Remove the superfluous unlock. Technically the problem was already
present before 5ac49f3c2702 as that commit only replaced the locking
primitive, but no functional change.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 5ac49f3c2702 ("iavf: use mutexes for locking of critical sections")
Fixes: bac8486116b0 ("iavf: Refactor the watchdog state machine")
Signed-off-by: Stefan Assmann <sassmann@kpanic.de>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
---
 drivers/net/ethernet/intel/iavf/iavf_main.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
index 23762a7ef740..cada4e0e40b4 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
@@ -1965,7 +1965,6 @@ static void iavf_watchdog_task(struct work_struct *work)
 		}
 		adapter->aq_required = 0;
 		adapter->current_op = VIRTCHNL_OP_UNKNOWN;
-		mutex_unlock(&adapter->crit_lock);
 		queue_delayed_work(iavf_wq,
 				   &adapter->watchdog_task,
 				   msecs_to_jiffies(10));
-- 
2.31.1

Re: [PATCH net 0/3][pull request] Intel Wired LAN Driver Updates 2021-10-06

[patchwork-bot+netdevbpf]

Hello:

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

On Wed,  6 Oct 2021 09:56:56 -0700 you wrote:
> This series contains updates to i40e and iavf drivers.
> 
> Jiri Benc expands an error check to prevent infinite loop for i40e.
> 
> Sylwester prevents freeing of uninitialized IRQ vector to resolve a
> kernel oops for i40e.
> 
> [...]

Here is the summary with links:
  - [net,1/3] i40e: fix endless loop under rtnl
    https://git.kernel.org/netdev/net/c/857b6c6f665c
  - [net,2/3] i40e: Fix freeing of uninitialized misc IRQ vector
    https://git.kernel.org/netdev/net/c/2e5a20573a92
  - [net,3/3] iavf: fix double unlock of crit_lock
    https://git.kernel.org/netdev/net/c/54ee39439acd

You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html