i40e: synchronize nvmupdate command and adminq subtask

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 373149fc99
("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 <sudheer.mogilappagari@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This commit is contained in:
Sudheer Mogilappagari 2017-07-12 05:46:07 -04:00 committed by Jeff Kirsher
parent 06b2decd92
commit 2bf01935ec
1 changed files with 6 additions and 0 deletions

View File

@ -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;
}