Commit 2bf01935 authored Jul 12, 2017 by Sudheer Mogilappagari Committed by Jeff Kirsher Aug 25, 2017

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 373149fc
("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>

parent 06b2decd

drivers/net/ethernet/intel/i40e/i40e_nvm.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -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;
		}