From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alice Michael Date: Thu, 29 Jun 2017 04:36:35 -0400 Subject: [Intel-wired-lan] [next PATCH S75-V2 04/12] i40e: synchronize nvmupdate command and adminq subtask In-Reply-To: <20170629083643.82018-1-alice.michael@intel.com> References: <20170629083643.82018-1-alice.michael@intel.com> Message-ID: <20170629083643.82018-4-alice.michael@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: intel-wired-lan@osuosl.org List-ID: From: Sudheer Mogilappagari During NVM update, state machine gets into unrecoverable state because i40e_clean_adminq_subtask can get scheduled after the admin queue command but before other state variables are updated. This causes incorrect input to i40e_nvmupd_check_wait_event and state transitions don't happen. This issue existed before but surfaced after commit 373149fc99a0 ("i40e: Decrease the scope of rtnl lock") This fix adds locking around admin queue command and update of state variables so that adminq_subtask will have accurate information whenever it gets scheduled. Signed-off-by: Sudheer Mogilappagari --- drivers/net/ethernet/intel/i40e/i40e_nvm.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/ethernet/intel/i40e/i40e_nvm.c b/drivers/net/ethernet/intel/i40e/i40e_nvm.c index 17607a2..04f2192 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_nvm.c +++ b/drivers/net/ethernet/intel/i40e/i40e_nvm.c @@ -753,6 +753,11 @@ i40e_status i40e_nvmupd_command(struct i40e_hw *hw, hw->nvmupd_state = I40E_NVMUPD_STATE_INIT; } + /* Acquire lock to prevent race condition where adminq_task + * can execute after i40e_nvmupd_nvm_read/write but before state + * variables (nvm_wait_opcode, nvm_release_on_done) are updated + */ + mutex_lock(&hw->aq.arq_mutex); switch (hw->nvmupd_state) { case I40E_NVMUPD_STATE_INIT: status = i40e_nvmupd_state_init(hw, cmd, bytes, perrno); @@ -788,6 +793,7 @@ i40e_status i40e_nvmupd_command(struct i40e_hw *hw, *perrno = -ESRCH; break; } + mutex_unlock(&hw->aq.arq_mutex); return status; } -- 2.9.3