diff options
| author | Jiri Benc <jbenc@redhat.com> | 2021-09-14 10:54:42 +0200 |
|---|---|---|
| committer | Tony Nguyen <anthony.l.nguyen@intel.com> | 2021-10-06 18:49:23 +0200 |
| commit | 857b6c6f665cca9828396d9743faf37fd09e9ac3 (patch) | |
| tree | 2bc83e58b484af6d5ae830f971dc381dcef009a6 /drivers/net | |
| parent | dt-bindings: net: dsa: marvell: fix compatible in example (diff) | |
| download | linux-857b6c6f665cca9828396d9743faf37fd09e9ac3.tar.xz linux-857b6c6f665cca9828396d9743faf37fd09e9ac3.zip | |
i40e: fix endless loop under rtnl
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>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/ethernet/intel/i40e/i40e_main.c | 2 |
1 files changed, 1 insertions, 1 deletions
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), |